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The YARN Timeline Server
========================

* [Overview](#Overview)
    * [Introduction](#Introduction)
    * [Current Status](#Current_Status)
    * [Timeline Structure](#Timeline_Structure)
* [Deployment](#Deployment)
    * [Configurations](#Configurations)
    * [Running the Timeline Server](#Running_Timeline_Server)
    * [Accessing generic-data via command-line](#Accessing_generic-data_via_command-line)
* [Publishing of application specific data](#Publishing_of_application_specific_data)
* [Timeline Server REST API](#Timeline_Server_REST_API_v1)
* [Generic Data REST APIs](#GENERIC_DATA_REST_APIS)

<a name="Overview"></a>Overview
---------

### <a name="Introduction"></a>Introduction

The Storage and retrieval of application's current and historic information in a
generic fashion is addressed in YARN through the Timeline Server. It has two responsibilities:

#### Persisting Application Specific Information

The collection and retrieval of information completely specific to an application or framework.
For example, the Hadoop MapReduce framework can include pieces of information like number of
map tasks, reduce tasks, counters...etc.
Application developers can publish the specific information to the Timeline server via `TimelineClient`
in the Application Master and/or the application's containers.

This information is then queryable via REST APIs for rendering by application/framework specific UIs.

#### Persisting Generic Information about Completed Applications

Previously this was supported purely for MapReduce jobs by the Application History Server.
With the introduction of the timeline server, the Application History Server becomes just one use of
the Timeline Server.

Generic information includes application level data such as 
* queue-name, 
* user information and the like set in the `ApplicationSubmissionContext`,
* a list of application-attempts that ran for an application
* information about each application-attempt
* the list of containers run under each application-attempt
* information about each container.

Generic data is published by the YARN Resource Manager to the timeline store
 and used by its web-UI to display information about completed applications.

### <a name="Current_Status"></a>Current Status and Future Plans


Current status

1. The core functionality of the timeline server has been completed.
1. It works in both secure and non secure clusters.
1. The generic history service is built on the timeline store.
1. The history can be stored in memory or in a leveldb database store;
  the latter ensures the history is preserved over Timeline Server restarts.
1. The ability to install framework specific UIs in YARN is not supported.
1. Application specific information is only available via RESTful APIs using JSON type content.
1. The "Timeline Server v1" REST API has been declared one of the REST APIs
  whose compatibility will be maintained in future releases.
1. The single-server implementation of the Timeline Server places a limit on
  the scalability of the service; it also prevents the service being 
  High-Availability component of the YARN infrastructure.

Future Plans

1. Future releases will introduce a next generation timeline service
which is scalable and reliable, "Timeline Server v2".
1. The expanded features of this service *may not* be available to
applications using the Timeline Server v1 REST API. That includes extended
data structures as well as the ability of the client to failover between Timeline Server instances.

### <a name="Timeline_Structure"></a>Timeline Structure

![Timeline Structure](./images/timeline_structure.jpg)

#### Timeline Domain

The Timeline Domain offers a namespace for Timeline server allowing
users to host multiple entities, isolating them from other users and applications.
Timeline server Security is defined at this level.
 
A "Domain" primarily stores owner info, read and& write ACL information,
created and modified time stamp information. Each Domain is identified by an ID which 
must be unique across all users in the YARN cluster.

#### Timeline Entity

A Timeline Entity contains the the meta information of a conceptual entity
and its related events.

The entity can be an application, an application attempt, a container or
any user-defined object.

It contains **Primary filters** which will be used to index the entities
in the Timeline Store. Accordingly, users/applications should carefully
choose the information they want to store as the primary filters.

The remaining data can be stored as unindexed information.
Each Entity is uniquely identified by an `EntityId` and `EntityType`.

#### Timeline Events

A Timeline Event describes an event that is related to a specific
Timeline Entity of an application. 

Users are free to define what an event means —such as starting
an application, getting allocated a container,
an operation failures or other information considered relevant to users
and cluster operators.


<a name="Deployment"></a>Deployment
----------

###<a name="Configurations"></a>Configurations

#### Basic Configuration

| Configuration Property | Description |
|:---- |:---- |
| `yarn.timeline-service.enabled` | Indicate to clients whether Timeline service is enabled or not. If enabled, the `TimelineClient` library used by applications will post entities and events to the Timeline server. Defaults to `false`. |
| `yarn.resourcemanager.system-metrics-publisher.enabled` | The setting that controls whether or not YARN system metrics are published on the timeline server by RM. Defaults to `false`. |
| `yarn.timeline-service.generic-application-history.enabled` | Indicate to clients whether to query generic application data from timeline history-service or not. If not enabled then application data is queried only from Resource Manager. Defaults to `false`. |

#### Timeline store and state store configuration

| Configuration Property | Description |
|:---- |:---- |
| `yarn.timeline-service.store-class` | Store class name for timeline store. Defaults to `org.apache.hadoop.yarn.server.timeline.LeveldbTimelineStore`. |
| `yarn.timeline-service.leveldb-timeline-store.path` | Store file name for leveldb timeline store. Defaults to `${hadoop.tmp.dir}/yarn/timelin`e. |
| `yarn.timeline-service.leveldb-timeline-store.ttl-interval-ms` | Length of time to wait between deletion cycles of leveldb timeline store in milliseconds. Defaults to `300000`. |
| `yarn.timeline-service.leveldb-timeline-store.read-cache-size` | Size of read cache for uncompressed blocks for leveldb timeline store in bytes. Defaults to `104857600`. |
| `yarn.timeline-service.leveldb-timeline-store.start-time-read-cache-size` | Size of cache for recently read entity start times for leveldb timeline store in number of entities. Defaults to `10000`. |
| `yarn.timeline-service.leveldb-timeline-store.start-time-write-cache-size` | Size of cache for recently written entity start times for leveldb timeline store in number of entities. Defaults to `10000`. |
| `yarn.timeline-service.recovery.enabled` | Defaults to `false`. |
| `yarn.timeline-service.state-store-class` | Store class name for timeline state store. Defaults to `org.apache.hadoop.yarn.server.timeline.recovery.LeveldbTimelineStateStore`. |
| `yarn.timeline-service.leveldb-state-store.path` | Store file name for leveldb timeline state store. |

#### Web and RPC Configuration

| Configuration Property | Description |
|:---- |:---- |
| `yarn.timeline-service.hostname` | The hostname of the Timeline service web application. Defaults to `0.0.0.0` |
| `yarn.timeline-service.address` | Address for the Timeline server to start the RPC server. Defaults to `${yarn.timeline-service.hostname}:10200`. |
| `yarn.timeline-service.webapp.address` | The http address of the Timeline service web application. Defaults to `${yarn.timeline-service.hostname}:8188`. |
| `yarn.timeline-service.webapp.https.address` | The https address of the Timeline service web application. Defaults to `${yarn.timeline-service.hostname}:8190`. |
| `yarn.timeline-service.bind-host` | The actual address the server will bind to. If this optional address is set, the RPC and webapp servers will bind to this address and the port specified in `yarn.timeline-service.address` and `yarn.timeline-service.webapp.address`, respectively. This is most useful for making the service listen on all interfaces by setting to `0.0.0.0`. |
| `yarn.timeline-service.http-cross-origin.enabled` | Enables cross-origin support (CORS) for web services where cross-origin web response headers are needed. For example, javascript making a web services request to the timeline server. Defaults to `false`. |
| `yarn.timeline-service.http-cross-origin.allowed-origins` | Comma separated list of origins that are allowed for web services needing cross-origin (CORS) support. Wildcards `(*)` and patterns allowed. Defaults to `*`. |
| `yarn.timeline-service.http-cross-origin.allowed-methods` | Comma separated list of methods that are allowed for web services needing cross-origin (CORS) support. Defaults to `GET,POST,HEAD`. |
| `yarn.timeline-service.http-cross-origin.allowed-headers` | Comma separated list of headers that are allowed for web services needing cross-origin (CORS) support. Defaults to `X-Requested-With,Content-Type,Accept,Origin`. |
| `yarn.timeline-service.http-cross-origin.max-age` | The number of seconds a pre-flighted request can be cached for web services needing cross-origin (CORS) support. Defaults to `1800`. |

Note that the selection between the HTTP and HTTPS binding is made in the `TimelineClient` based
upon the value of the YARN-wide configuration option `yarn.http.policy`; the HTTPS endpoint will be
selected if this policy is either of `HTTPS_ONLY` or `HTTP_AND_HTTPS`.

#### Advanced Server-side configuration

| Configuration Property | Description |
|:---- |:---- |
| `yarn.timeline-service.ttl-enable` | Enable deletion of aged data within the timeline store. Defaults to `true`. |
| `yarn.timeline-service.ttl-ms` | Time to live for timeline store data in milliseconds. Defaults to `604800000` (7 days). |
| `yarn.timeline-service.handler-thread-count` | Handler thread count to serve the client RPC requests. Defaults to `10`. |
| `yarn.timeline-service.client.max-retries` | The maximum number of retries for attempts to publish data to the timeline service.Defaults to `30`. |
| `yarn.timeline-service.client.retry-interval-ms` | The interval in milliseconds between retries for the timeline service client. Defaults to `1000`. |



#### Security Configuration


Security can be enabled by setting `yarn.timeline-service.http-authentication.type`
to `kerberos`, after which the following configuration options are available:


| Configuration Property | Description |
|:---- |:---- |
| `yarn.timeline-service.http-authentication.type` | Defines authentication used for the timeline server HTTP endpoint. Supported values are: `simple` / `kerberos` / #AUTHENTICATION_HANDLER_CLASSNAME#. Defaults to `simple`. |
| `yarn.timeline-service.http-authentication.simple.anonymous.allowed` | Indicates if anonymous requests are allowed by the timeline server when using 'simple' authentication. Defaults to `true`. |
| `yarn.timeline-service.principal` | The Kerberos principal for the timeline server. |
| `yarn.timeline-service.keytab` | The Kerberos keytab for the timeline server. Defaults on Unix to to `/etc/krb5.keytab`. |
| `yarn.timeline-service.delegation.key.update-interval` | Defaults to `86400000` (1 day). |
| `yarn.timeline-service.delegation.token.renew-interval` | Defaults to `86400000` (1 day). |
| `yarn.timeline-service.delegation.token.max-lifetime` | Defaults to `604800000` (7 days). |
| `yarn.timeline-service.best-effort` | Should the failure to obtain a delegation token be considered an application failure (option = false),  or should the client attempt to continue to publish information without it (option=true). Default: `false` |

#### Enabling the timeline service and the generic history service

  Following are the basic configuration to start Timeline server.

```
<property>
  <description>Indicate to clients whether Timeline service is enabled or not.
  If enabled, the TimelineClient library used by end-users will post entities
  and events to the Timeline server.</description>
  <name>yarn.timeline-service.enabled</name>
  <value>true</value>
</property>

<property>
  <description>The setting that controls whether yarn system metrics is
  published on the timeline server or not by RM.</description>
  <name>yarn.resourcemanager.system-metrics-publisher.enabled</name>
  <value>true</value>
</property>

<property>
  <description>Indicate to clients whether to query generic application
  data from timeline history-service or not. If not enabled then application
  data is queried only from Resource Manager.</description>
  <name>yarn.timeline-service.generic-application-history.enabled</name>
  <value>true</value>
</property>
```

###<a name="Running_Timeline_Server"></a> Running the Timeline Server

Assuming all the aforementioned configurations are set properly
admins can start the Timeline server/history service with the following command:

    yarn timelineserver

To start the Timeline server / history service as a daemon, the command is

    $HADOOP_YARN_HOME/sbin/yarn-daemon.sh start timelineserver

###<a name="Accessing_generic-data_via_command-line"></a> Accessing generic-data via command-line

Users can access applications' generic historic data via the command line below

    $ yarn application -status <Application ID>
    $ yarn applicationattempt -list <Application ID>
    $ yarn applicationattempt -status <Application Attempt ID>
    $ yarn container -list <Application Attempt ID>
    $ yarn container -status <Container ID>

Note that the same commands are usable to obtain the corresponding information about running applications.

###<a name="Publishing_of_application_specific_data"></a> Publishing application specific data

Developers can define what information they want to record for
their applications by constructing `TimelineEntity` and  `TimelineEvent` objects
then publishing the entities and events to the Timeline Server
via the `TimelineClient` API.

Here is an example:


    // Create and start the Timeline client
    TimelineClient client = TimelineClient.createTimelineClient();
    client.init(conf);
    client.start();

    try {
      TimelineDomain myDomain = new TimelineDomain();
      myDomain.setID("MyDomain");
      // Compose other Domain info ....

      client.putDomain(myDomain);

      TimelineEntity myEntity = new TimelineEntity();
      myEntity.setDomainId(myDomain.getId());
      myEntity.setEntityType("APPLICATION");
      myEntity.setEntityID("MyApp1")
      // Compose other entity info

      TimelinePutResponse response = client.putEntities(entity);

      TimelineEvent event = new TimelineEvent();
      event.setEventType("APP_FINISHED");
      event.setTimestamp(System.currentTimeMillis());
      event.addEventInfo("Exit Status", "SUCCESS");
      // Compose other Event info ....

      myEntity.addEvent(event);
      TimelinePutResponse response = timelineClient.putEntities(entity);

    } catch (IOException e) {
      // Handle the exception
    } catch (RuntimeException e) {
      // In Hadoop 2.6, if attempts submit information to the Timeline Server fail more than the retry limit,
      // a RuntimeException will be raised. This may change in future releases, being
      // replaced with a IOException that is (or wraps) that which triggered retry failures.
    } catch (YarnException e) {
      // Handle the exception
    } finally {
      // Stop the Timeline client
      client.stop();
    }


1. Publishing of data to Timeline Server is a synchronous operation; the call will not return until successful.
1. The `TimelineClient` implementation class is a subclass of the YARN `Service` API; it can be placed
under a `CompositeService` to ease its lifecycle management.
1. The result of a `putEntities()` call is a `TimelinePutResponse` object. This contains a
(hopefully empty) list of those timeline entities reject by the timeline server, along with
an error code indicating the cause of each failure.

In Hadoop 2.6 and 2.7, the error codes are:

| Error Code | Description |
|:---- |:---- |
|1 | No start time |
|2 | IOException |
|3 | System Filter conflict (reserved filter key used) |
|4 | Access Denied |
|5 | No domain |
|6 | Forbidden relation |

Further error codes may be defined in future.

**Note** : Following are the points which need to be observed when updating a entity.

* Domain ID should not be modified for already existing entity.
* After a modification of a Primary filter value, the new value
will be appended to the old value; the original value will not be replaced.
* It's advisable to have same primary filters for all updates on entity.
Any on modification of a primary filter by in an update will result in
queries with updated primary filter to not fetching the information before the update

# Generic Data Web UI

Users can access the generic historic information of applications via web UI:

    http(s)://<timeline server http(s) address:port>/applicationhistory

## <a name="Timeline_Server_REST_API_v1"></a>Timeline Server REST API V1

Querying the timeline server is currently only supported via REST API calls; there is no API
client implemented in the YARN libraries. In Java, the Jersey client is effective at querying
the server, even in secure mode (provided the caller has the appropriate Kerberos tokens or keytab).

The v1 REST API is implemented at under the path, `/ws/v1/timeline/` on the Timeline Server web service.

Here is a non-normative description of the API.

### Root path

    GET /ws/v1/timeline/

Returns a JSON object describing the server instance.

     {"About":"Timeline API"}


## <a name="REST_API_DOMAINS"></a>Domains `/ws/v1/timeline/domain`

### Domain summary information `/ws/v1/timeline/domain`


    GET /ws/v1/timeline/domain?owner=$OWNER

Returns a list of domains belonging to a specific user, in
the JSON-marshalled `TimelineDomains` data structure.

The `owner` MUST be set on a GET which is not authenticated.

On an authenticated request, the `owner` defaults to
the caller.

    PUT /ws/v1/timeline/domain

A PUT of a serialized `TimelineDomain` structure to this path will
add the domain to the list of domains owned by the specified/current
user. A successful operation returns status code of 200 and
a `TimelinePutResponse` containing no errors.


### Specific information about a Domain `/ws/v1/timeline/domain/{domainId}`

Returns a JSON-marshalled `TimelineDomain` structure
describing a domain.

If the domain is not found, then an HTTP 404 response is returned.


### POST new domain `/ws/v1/timeline/domain`

Creates a new timeline domain, or overrides an existing one.

When attempting to create a new domain, the ID in the submission MUST
be unique across all domains in the cluster.

When attempting to update an existing domain, the ID of that domain
must be set. The submitter must have the appropriate permissions
to update the domain.

submission: `TimelineDomain`

response: `TimelinePutResponse`

### List domains of a user: GET `/ws/v1/timeline/domain`

Retrieves a list of all domains of a user. 

If an owner is specified, that owner name overrides that of the caller.

| Query Parameter | Description |
|:---- |:---- |
| `owner`| owner of the domains to list|


    GET http://localhost:8188/ws/v1/timeline/domain?owner=alice

    {
    "domains":
      [
        {
        "id":"DS_DOMAIN_2",
        "owner":"alice",
        "readers":"peter",
        "writers":"john",
        "createdtime":1430425000337,
        "modifiedtime":1430425000337
        },
        {
        "id":"DS_DOMAIN_1",
        "owner":"alice",
        "readers":"bar",
        "writers":"foo",
        "createdtime":1430424955963,
        "modifiedtime":1430424955963
        }
        ,
        {"id":"DEFAULT",
        "description":"System Default Domain",
        "owner":"alice",
        "readers":"*",
        "writers":"*",
        "createdtime":1430424022699,
        "modifiedtime":1430424022699
        }
      ]
    }

response: `TimelineDomains`

If the user lacks the permission to list the domains of the specified
owner, an `TimelineDomains` response with no domain listings is
returned.

#### Retrieve details of a specific domain: GET `/ws/v1/timeline/domain/{domainId}`

Retrieves the details of a single domain

    GET http://localhost:8188/ws/v1/timeline/domain/DS_DOMAIN_1

Response: `TimelineDomain`

    {
      "id":"DS_DOMAIN_1",
      "owner":"zshen",
      "readers":"bar",
      "writers":"foo",
      "createdtime":1430424955963,
      "modifiedtime":1430424955963
    }


If the user lacks the permission to query the details of that domain,
a 404, not found exception is returned —the same response which
is returned if there is no entry with that ID.


## <a name="REST_API_POST_TIMELINE_ENTITIES"></a> Posting Timeline Entities

With the Posting Entities API, you can post the entities and events, which
contain the per-framework information you want to record, to the timeline
server.

### URI:

    http(s)://<timeline server http(s) address:port>/ws/v1/timeline

### HTTP Operations Supported:

    POST

### Query Parameters Supported:

None

### response: `TimelinePutResponse`


### Request Examples:

#### JSON request

HTTP Request:

    POST http://<timeline server http address:port>/ws/v1/timeline

Request Header:

    POST /ws/v1/timeline HTTP/1.1
    Accept: application/json
    Content-Type: application/json
    Transfer-Encoding: chunked

Request Body:

    {
      "entities" : [ {
        "entity" : "entity id 0",
        "entitytype" : "entity type 0",
        "relatedentities" : {
          "test ref type 2" : [ "test ref id 2" ],
          "test ref type 1" : [ "test ref id 1" ]
        },
        "events" : [ {
          "timestamp" : 1395818851590,
          "eventtype" : "event type 0",
          "eventinfo" : {
            "key2" : "val2",
            "key1" : "val1"
          }
        }, {
          "timestamp" : 1395818851590,
          "eventtype" : "event type 1",
          "eventinfo" : {
            "key2" : "val2",
            "key1" : "val1"
          }
        } ],
        "primaryfilters" : {
          "pkey2" : [ "pval2" ],
          "pkey1" : [ "pval1" ]
        },
        "otherinfo" : {
          "okey2" : "oval2",
          "okey1" : "oval1"
        },
        "starttime" : 1395818851588
      }, {
        "entity" : "entity id 1",
        "entitytype" : "entity type 0",
        "relatedentities" : {
          "test ref type 2" : [ "test ref id 2" ],
          "test ref type 1" : [ "test ref id 1" ]
        },
        "events" : [ {
          "timestamp" : 1395818851590,
          "eventtype" : "event type 0",
          "eventinfo" : {
            "key2" : "val2",
            "key1" : "val1"
          }
        }, {
          "timestamp" : 1395818851590,
          "eventtype" : "event type 1",
          "eventinfo" : {
            "key2" : "val2",
            "key1" : "val1"
          }
        } ],
        "primaryfilters" : {
          "pkey2" : [ "pval2" ],
          "pkey1" : [ "pval1" ]
        },
        "otherinfo" : {
          "okey2" : "oval2",
          "okey1" : "oval1"
        },
        "starttime" : 1395818851590
      } ]
    }

Required fields

Entity: `type` and `id`. `starttime` is required unless the
entity contains one or more event). 
Event: `type` and `timestamp`. 

## <a name="REST_API_LIST_TIMELINE_ENTITIES"></a>Timeline Entity List

With the Timeline Entity List API,  you can retrieve a list of entity object,
sorted by the starting timestamp for the entity, descending. The starting
timestamp of an entity can be a timestamp specified by the your application.
If it is not explicitly specified, it will be chosen by the store to be the
earliest timestamp of the events received in the first post for the entity.

### URI:

Use the following URI to obtain all the entity objects of a given
`entityType`.

    http(s)://<timeline server http(s) address:port>/ws/v1/timeline/{entityType}

### HTTP Operations Supported:

    GET  http://localhost:8188/ws/v1/timeline/DS_APP_ATTEMPT


### Query Parameters Supported:

1. `limit` - A limit on the number of entities to return. If null, defaults to 100.
1. `windowStart` - The earliest start timestamp to retrieve (exclusive). If
  null, defaults to retrieving all entities until the limit is reached.
1. `windowEnd` - The latest start timestamp to retrieve (inclusive). If null,
  defaults to the max value of Long.
1. `fromId` - If `fromId` is not null, retrieve entities earlier than and
  including the specified ID. If no start time is found for the specified ID,
  an empty list of entities will be returned. The `windowEnd` parameter will take
  precedence if the start time of this entity falls later than `windowEnd`.
1. `fromTs` - If `fromTs` is not null, ignore entities that were inserted into the
  store after the given timestamp. The entity's insert timestamp used for this
  comparison is the store's system time when the first put for the entity was
  received (not the entity's start time).
1. `primaryFilter` - Retrieves only entities that have the specified primary
  filter. If null, retrieves all entities. This is an indexed retrieval, and no
  entities that do not match the filter are scanned.
1. `secondaryFilters` - Retrieves only entities that have exact matches for all
  the specified filters in their primary filters or other info. This is not an
  indexed retrieval, so all entities are scanned but only those matching the
  filters are returned.
1. fields - Specifies which fields of the entity object to retrieve:
  `EVENTS`, `RELATED_ENTITIES`, `PRIMARY_FILTERS`, `OTHER_INFO`, `LAST_EVENT_ONLY`. If
  the set of fields contains `LAST_EVENT_ONLY` and not `EVENTS`, the most recent
  event for each entity is retrieved. If null, retrieves all fields.

### Elements of the `entities` (Timeline Entity List) Object

When you make a request for the list of timeline entities, the information
will be returned as a collection of container objects. See also
{{Timeline Entity}} for syntax of the timeline entity object.

| Item | Data Type | Description|
|:---- |:---- |:---- |
| `entities` | array of timeline entity objects(JSON) | The collection of timeline entity objects |

### Response Examples:

#### JSON response

HTTP Request:

    GET http://<timeline server http address:port>/ws/v1/timeline/{entity-type}

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:


    {
      "entities":[
      {
      "entitytype":"DS_APP_ATTEMPT",
      "entity":"appattempt_1430424020775_0004_000001",
      "events":[
        {
        "timestamp":1430425008796,
        "eventtype":"DS_APP_ATTEMPT_END",
        "eventinfo": { }
        }
        {
        "timestamp":1430425004161,
        "eventtype":"DS_APP_ATTEMPT_START",
        "eventinfo": { }
        }
      ]
      "starttime":1430425004161,
      "domain":"DS_DOMAIN_2",
      "relatedentities": { },
      "primaryfilters":
        {
        "user":["zshen"]
        },
      "otherinfo": { }
      }
      {
      "entitytype":"DS_APP_ATTEMPT",
      "entity":"appattempt_1430424020775_0003_000001",
      "starttime":1430424959169,
      "domain":"DS_DOMAIN_1",
      "events":[
        {
        "timestamp":1430424963836,
        "eventinfo": { }
         }
        {
        "timestamp":1430424959169,
        "eventinfo": { }
        }
       ]
      "relatedentities": { },
      "primaryfilters": {
        "user":["zshen"]
       },
      "otherinfo": { }
       }
      ]
    }


## <a name="REST_API_GET_TIMELINE_ENTITY"></a>Timeline Entity

With the Timeline Entity API, you can retrieve the entity information for a
given entity identifier.

### URI:

Use the following URI to obtain the entity object identified by the
`entityType` value and the `entityId` value.

    http(s)://<timeline server http(s) address:port>/ws/v1/timeline/{entityType}/{entityId}

### HTTP Operations Supported:

    GET

### Query Parameters Supported:

1. fields - Specifies which fields of the entity object to retrieve:
  `EVENTS`, `RELATED_ENTITIES`, `PRIMARY_FILTERS`, `OTHER_INFO`, `LAST_EVENT_ONLY`. If
  the set of fields contains LAST_EVENT_ONLY and not EVENTS, the most recent
  event for each entity is retrieved. If null, retrieves all fields.

### Elements of the `entity` (Timeline Entity) Object:

See also {{Timeline Event List}} for syntax of the timeline event object.


| Item | Data Type | Description|
|:---- |:---- |:---- |
| `entity` | string  | The entity id |
| `entitytype` | string | The entity type |
| `relatedentities` | map | The related entities' identifiers, which are organized in a map of entityType : [entity1, entity2, ...] |
| `events` | list | The events of the entity |
| `primaryfilters` | map | The primary filters of the entity, which are orgainzied in a map of key : [value1, value2, ...] |
| `otherinfo` | map | The other information of the entity, which is orgainzied in a map of key : value |
| `starttime` | long | The start time of the entity |

### Response Examples:

#### JSON response

HTTP Request:

    GET http://<timeline server http address:port>/ws/v1/timeline/{entity-type}/{entity-id}

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:

    http://localhost:8188/ws/v1/timeline/DS_APP_ATTEMPT/appattempt_1430424020775_0003_000001

    {
      "events":[
        {
        "timestamp":1430424959169,
        "eventtype":"DS_APP_ATTEMPT_START",
        "eventinfo":  {}}],
        "entitytype":"DS_APP_ATTEMPT",
        "entity":"appattempt_1430424020775_0003_000001",
        "starttime":1430424959169,
        "domain":"DS_DOMAIN_1",
        "relatedentities":  {},
        "primaryfilters":  {
            "user":["zshen"]
            },
        "otherinfo":  {}
        }
      ]
    }
  



## <a name="REST_API_LIST_TIMELINE_EVENTS"></a>Timeline Event List

With the Timeline Events API, you can retrieve the event objects for a list
of entities all of the same entity type. The events for each entity are
sorted in order of their timestamps, descending.

### URI:

Use the following URI to obtain the event objects of the given `entityType`.

    http(s)://<timeline server http(s) address:port>/ws/v1/timeline/{entityType}/events

### HTTP Operations Supported:

    GET

### Query Parameters Supported:

1. `entityIds` - The entity IDs to retrieve events for.
1. `limit` - A limit on the number of events to return for each entity. If null,
  defaults to 100 events per entity.
1. `windowStart` - If not null, retrieves only events later than the given time
  (exclusive)
1. `windowEnd` - If not null, retrieves only events earlier than the given time
  (inclusive)
1. `eventTypes` - Restricts the events returned to the given types. If null,
  events of all types will be returned.

### Elements of the `events` (Timeline Entity List) Object

When you make a request for the list of timeline events, the information
will be returned as a collection of event objects.

| Item | Data Type | Description|
|:---- |:---- |:---- |
| `events` | array of timeline event objects(JSON) | The collection of timeline event objects |

Below is the elements of a single event object.


| Item | Data Type | Description|
|:---- |:---- |:---- |
| `eventtype` | string  | The event type |
| `eventinfo` | map | The information of the event, which is orgainzied in a map of `key` : `value` |
| `timestamp` | long | The timestamp of the event |

### Response Examples:

#### JSON response

HTTP Request:

    GET http://<timeline server http address:port>/ws/v1/timeline/entity%20type%200/events

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:


    GET http://localhost:8188/ws/v1/timeline/DS_APP_ATTEMPT/events?entityId=appattempt_1430424020775_0003_000001
    
    
    {
    "events": [
      {
      "entity":"appattempt_1430424020775_0003_000001",
      "entitytype":"DS_APP_ATTEMPT"}
      "events":[
        {
        "timestamp":1430424963836,
        "eventtype":"DS_APP_ATTEMPT_END",
        "eventinfo":{}},
        {
        "timestamp":1430424959169,
        "eventtype":"DS_APP_ATTEMPT_START",
        "eventinfo":{}}
        ],
       }
      ]
    }





#<a name="GENERIC_DATA_REST_APIS"></a> Generic Data REST APIs

Users can access the generic historic information of applications via REST
APIs.

## <a name="REST_API_LIST_APPLICATIONS"></a>Application List

With the Application List API, you can obtain a collection of resources, each
of which represents an application. When you run a GET operation on this
resource, you obtain a collection of application objects.

### URI:

    http(s)://<timeline server http(s) address:port>/ws/v1/applicationhistory/apps

### HTTP Operations Supported:

    GET

### Query Parameters Supported:

1. `states` - applications matching the given application states, specified as a
comma-separated list

1. `finalStatus` - the final status of the application - reported by the
application itself

1. `user` - user name

1. `queue` - queue name

1. `limit` - total number of app objects to be returned

1. `startedTimeBegin` - applications with start time beginning with this time,
specified in ms since epoch

1. `startedTimeEnd` - applications with start time ending with this time,
specified in ms since epoch

1. `finishedTimeBegin` - applications with finish time beginning with this time,
specified in ms since epoch

1. `finishedTimeEnd` - applications with finish time ending with this time,
specified in ms since epoch

1. `applicationTypes` - applications matching the given application types,
specified as a comma-separated list

### Elements of the `apps` (Application List) Object

When you make a request for the list of applications, the information will be
returned as a collection of application objects. See also `Application` for
syntax of the application object.

| Item  | Data Type | Description  |
|:---- |:---- |:---- |
| `app` | array of app objects(JSON)/zero or more application objects(XML) | The collection of application objects |

### Response Examples:

#### JSON response

HTTP Request:

    GET http://<timeline server http address:port>/ws/v1/applicationhistory/apps

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:


    {
      "app":
      [
          {
          "appId":"application_1430424020775_0004",
          "currentAppAttemptId":"appattempt_1430424020775_0004_000001",
          "user":"zshen",
          "name":"DistributedShell",
          "queue":"default",
          "type":"YARN",
          "host":"d-69-91-129-173.dhcp4.washington.edu/69.91.129.173",
          "rpcPort":-1,
          "appState":"FINISHED",
          "progress":100.0,
          "diagnosticsInfo":"",
          "originalTrackingUrl":"N/A",
          "trackingUrl":"http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0004/",
          "finalAppStatus":"SUCCEEDED",
          "submittedTime":1430425001004,
          "startedTime":1430425001004,
          "finishedTime":1430425008861,
          "elapsedTime":7857},
          {
          "appId":"application_1430424020775_0003",
          "currentAppAttemptId":"appattempt_1430424020775_0003_000001",
          "user":"zshen",
          "name":"DistributedShell",
          "queue":"default",
          "type":"YARN",
          "host":"d-69-91-129-173.dhcp4.washington.edu/69.91.129.173",
          "rpcPort":-1,
          "appState":"FINISHED",
          "progress":100.0,
          "diagnosticsInfo":"",
          "originalTrackingUrl":"N/A",
          "trackingUrl":"http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0003/",
          "finalAppStatus":"SUCCEEDED",
          "submittedTime":1430424956650,
          "startedTime":1430424956650,
          "finishedTime":1430424963907,
          "elapsedTime":7257},
          {
          "appId":"application_1430424020775_0002",
          "currentAppAttemptId":"appattempt_1430424020775_0002_000001",
          "user":"zshen",
          "name":"DistributedShell",
          "queue":"default",
          "type":"YARN",
          "host":"d-69-91-129-173.dhcp4.washington.edu/69.91.129.173",
          "rpcPort":-1,
          "appState":"FINISHED",
          "progress":100.0,
          "diagnosticsInfo":"",
          "originalTrackingUrl":"N/A",
          "trackingUrl":"http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0002/",
          "finalAppStatus":"SUCCEEDED",
          "submittedTime":1430424769395,
          "startedTime":1430424769395,
          "finishedTime":1430424776594,
          "elapsedTime":7199
          }
      ]
    }



#### XML response

HTTP Request:

    GET http://localhost:8188/ws/v1/applicationhistory/apps

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/xml
    Content-Length: 1710

Response Body:

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
    <apps>
      <app>
        <appId>application_1430424020775_0004</appId>
        <currentAppAttemptId>appattempt_1430424020775_0004_000001</currentAppAttemptId>
        <user>zshen</user>
        <name>DistributedShell</name>
        <queue>default</queue>
        <type>YARN</type>
        <host>d-69-91-129-173.dhcp4.washington.edu/69.91.129.173</host>
        <rpcPort>-1</rpcPort>
        <appState>FINISHED</appState>
        <progress>100.0</progress>
        <diagnosticsInfo></diagnosticsInfo>
        <originalTrackingUrl>N/A</originalTrackingUrl>
        <trackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0004/</trackingUrl>
        <finalAppStatus>SUCCEEDED</finalAppStatus>
        <submittedTime>1430425001004</submittedTime>
        <startedTime>1430425001004</startedTime>
        <finishedTime>1430425008861</finishedTime>
        <elapsedTime>7857</elapsedTime>
      </app>
      <app>
        <appId>application_1430424020775_0003</appId>
        <currentAppAttemptId>appattempt_1430424020775_0003_000001</currentAppAttemptId>
        <user>zshen</user>
        <name>DistributedShell</name>
        <queue>default</queue>
        <type>YARN</type>
        <host>d-69-91-129-173.dhcp4.washington.edu/69.91.129.173</host>
        <rpcPort>-1</rpcPort>
        <appState>FINISHED</appState>
        <progress>100.0</progress>
        <diagnosticsInfo></diagnosticsInfo>
        <originalTrackingUrl>N/A</originalTrackingUrl>
        <trackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0003/</trackingUrl>
        <finalAppStatus>SUCCEEDED</finalAppStatus>
        <submittedTime>1430424956650</submittedTime>
        <startedTime>1430424956650</startedTime>
        <finishedTime>1430424963907</finishedTime>
        <elapsedTime>7257</elapsedTime>
      </app>
      <app>
        <appId>application_1430424020775_0002</appId>
        <currentAppAttemptId>appattempt_1430424020775_0002_000001</currentAppAttemptId>
        <user>zshen</user>
        <name>DistributedShell</name>
        <queue>default</queue>
        <type>YARN</type>
        <host>d-69-91-129-173.dhcp4.washington.edu/69.91.129.173</host>
        <rpcPort>-1</rpcPort>
        <appState>FINISHED</appState>
        <progress>100.0</progress>
        <diagnosticsInfo></diagnosticsInfo>
        <originalTrackingUrl>N/A</originalTrackingUrl>
        <trackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0002/</trackingUrl>
        <finalAppStatus>SUCCEEDED</finalAppStatus>
        <submittedTime>1430424769395</submittedTime>
        <startedTime>1430424769395</startedTime>
        <finishedTime>1430424776594</finishedTime>
        <elapsedTime>7199</elapsedTime>
      </app>
      <app>
        <appId>application_1430424020775_0001</appId>
        <currentAppAttemptId>appattempt_1430424020775_0001_000001</currentAppAttemptId>
        <user>zshen</user>
        <name>QuasiMonteCarlo</name>
        <queue>default</queue>
        <type>MAPREDUCE</type>
        <host>localhost</host>
        <rpcPort>56264</rpcPort>
        <appState>FINISHED</appState>
        <progress>100.0</progress>
        <diagnosticsInfo></diagnosticsInfo>
        <originalTrackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:19888/jobhistory/job/job_1430424020775_0001</originalTrackingUrl>
        <trackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0001/</trackingUrl>
        <finalAppStatus>SUCCEEDED</finalAppStatus>
        <submittedTime>1430424053809</submittedTime>
        <startedTime>1430424053809</startedTime>
        <finishedTime>1430424072153</finishedTime>
        <elapsedTime>18344</elapsedTime>
      </app>
    </apps>

## <a name="REST_API_GET_APPLICATION"></a>Application

With the Application API, you can get an application resource contains
information about a particular application that was running on an YARN
cluster.

It is essentially a JSON-serialized form of the YARN `ApplicationReport` structure.

### URI:

Use the following URI to obtain an application object identified by the `appid` value.

    http(s)://<timeline server http(s) address:port>/ws/v1/applicationhistory/apps/{appid}

### HTTP Operations Supported:

    GET

### Query Parameters Supported:

None

### Elements of the `app` (Application) Object:

| Item         | Data Type   | Description                   |
|:---- |:----  |:---- |
| `appId` | string  | The application ID |
| `user` | string  | The user who started the application |
| `name` | string  | The application name |
| `type` | string  | The application type |
| `queue` | string  | The queue to which the application submitted |
| `appState` | string | The application state according to the ResourceManager - valid values are members of the YarnApplicationState enum: `FINISHED`, `FAILED`, `KILLED` |
| `finalStatus` | string | The final status of the application if finished - reported by the application itself - valid values are: `UNDEFINED`, `SUCCEEDED`, `FAILED`, `KILLED` |
| `progress` | float | The reported progress of the application as a percent. Long-lived YARN services may not provide a meaninful value here —or use it as a metric of actual vs desired container counts |
| `trackingUrl` | string | The web URL of the application (via the RM Proxy) |
| `originalTrackingUrl` | string | The actual web URL of the application |
| `diagnosticsInfo` | string | Detailed diagnostics information on a completed application|
| `startedTime` | long | The time in which application started (in ms since epoch) |
| `finishedTime` | long | The time in which the application finished (in ms since epoch) |
| `elapsedTime` | long | The elapsed time since the application started (in ms) |
| `allocatedMB` | int | The sum of memory in MB allocated to the application's running containers |
| `allocatedVCores` | int | The sum of virtual cores allocated to the application's running containers |
| `currentAppAttemptId` | string | The latest application attempt ID |
| `host` | string | The host of the ApplicationMaster |
| `rpcPort` | int | The RPC port of the ApplicationMaster; zero if no IPC service declared. |

### Response Examples:

#### JSON response

HTTP Request:

    http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:

    {
      "appId": "application_1430424020775_0001",
      "currentAppAttemptId": "appattempt_1430424020775_0001_000001",
      "user": "zshen",
      "name": "QuasiMonteCarlo",
      "queue": "default",
      "type": "MAPREDUCE",
      "host": "localhost",
      "rpcPort": 56264,
      "appState": "FINISHED",
      "progress": 100.0,
      "diagnosticsInfo": "",
      "originalTrackingUrl": "http://d-69-91-129-173.dhcp4.washington.edu:19888/jobhistory/job/job_1430424020775_0001",
      "trackingUrl": "http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0001/",
      "finalAppStatus": "SUCCEEDED",
      "submittedTime": 1430424053809,
      "startedTime": 1430424053809,
      "finishedTime": 1430424072153,
      "elapsedTime": 18344
    }

#### XML response

HTTP Request:

    GET http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001
    Accept: application/xml

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/xml
    Content-Length: 873

Response Body:

     <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
     <app>
       <appId>application_1430424020775_0001</appId>
       <currentAppAttemptId>appattempt_1430424020775_0001_000001</currentAppAttemptId>
       <user>zshen</user>
       <name>QuasiMonteCarlo</name>
       <queue>default</queue>
       <type>MAPREDUCE</type>
       <host>localhost</host>
       <rpcPort>56264</rpcPort>
       <appState>FINISHED</appState>
       <progress>100.0</progress>
       <diagnosticsInfo></diagnosticsInfo>
       <originalTrackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:19888/jobhistory/job/job_1430424020775_0001</originalTrackingUrl>
       <trackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0001/</trackingUrl>
       <finalAppStatus>SUCCEEDED</finalAppStatus>
       <submittedTime>1430424053809</submittedTime>
       <startedTime>1430424053809</startedTime>
       <finishedTime>1430424072153</finishedTime>
       <elapsedTime>18344</elapsedTime>
     </app>

## <a name="REST_API_APPLICATION_ATTEMPT_LIST"></a>Application Attempt List

With the Application Attempt List API, you can obtain a collection of
resources, each of which represents an application attempt. When you run a
GET operation on this resource, you obtain a collection of application
attempt objects.

### URI:

Use the following URI to obtain all the attempt objects of an application
identified by the `appid` value.

    http(s)://<timeline server http(s) address:port>/ws/v1/applicationhistory/apps/{appid}/appattempts

### HTTP Operations Supported:

    GET

### Query Parameters Supported:

None

### Elements of the `appattempts` (Application Attempt List) Object

When you make a request for the list of application attempts, the information
will be returned as a collection of application attempt objects. See 
[Application Attempt](#REST_API_APPLICATION_ATTEMPT) for the syntax of 
the application attempt object.

| Item         | Data Type   | Description                  |
|:---- |:---- |:---- |
| `appattempt` | array of appattempt objects(JSON)/zero or more application attempt objects(XML) | The collection of application attempt objects |

### Response Examples:

#### JSON response

HTTP Request:

    GET  http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001/appattempts

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:

    {
      "appAttempt": [
        {
          "appAttemptId": "appattempt_1430424020775_0001_000001",
          "host": "localhost",
          "rpcPort": 56264,
          "trackingUrl": "http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0001/",
          "originalTrackingUrl": "http://d-69-91-129-173.dhcp4.washington.edu:19888/jobhistory/job/job_1430424020775_0001",
          "diagnosticsInfo": "",
          "appAttemptState": "FINISHED",
          "amContainerId": "container_1430424020775_0001_01_000001"
        }
      ]
    }

#### XML response

HTTP Request:

    GET http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001/appattempts
    Accept: application/xml

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/xml

Response Body:

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
    <appAttempts>
      <appAttempt>
        <appAttemptId>appattempt_1430424020775_0001_000001</appAttemptId>
        <host>localhost</host>
        <rpcPort>56264</rpcPort>
        <trackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0001/</trackingUrl>
        <originalTrackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:19888/jobhistory/job/job_1430424020775_0001</originalTrackingUrl>
        <diagnosticsInfo></diagnosticsInfo>
        <appAttemptState>FINISHED</appAttemptState>
        <amContainerId>container_1430424020775_0001_01_000001</amContainerId>
      </appAttempt>
    </appAttempts>

## <a name="REST_API_APPLICATION_ATTEMPT"></a>Application Attempt

With the Application Attempt API, you can get an application attempt resource
contains information about a particular application attempt of an application
that was running on an YARN cluster.

### URI:

Use the following URI to obtain an application attempt object identified by
the `appid` value and the `appattemptid` value.

    http(s)://<timeline server http(s) address:port>/ws/v1/applicationhistory/apps/{appid}/appattempts/{appattemptid}

### HTTP Operations Supported:

    GET

### Query Parameters Supported:

None

### Elements of the `appattempt` (Application Attempt) Object:


| Item | Data Type   | Description  |
|:---- |:---- |:---- |
| `appAttemptId` | string  | The application attempt Id |
| `amContainerId` | string  | The ApplicationMaster container Id |
| `appAttemptState` | string | The application attempt state according to the ResourceManager - valid values are members of the YarnApplicationAttemptState enum: FINISHED, FAILED, KILLED |
| `trackingUrl` | string | The web URL that can be used to track the application |
| `originalTrackingUrl` | string | The actual web URL of the application |
| `diagnosticsInfo` | string | Detailed diagnostics information |
| `host` | string | The host of the ApplicationMaster |
| `rpcPort` | int | The rpc port of the ApplicationMaster |

### Response Examples:

#### JSON response

HTTP Request:

    http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001/appattempts/appattempt_1430424020775_0001_000001

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:

    {
      "appAttemptId": "appattempt_1430424020775_0001_000001",
      "host": "localhost",
      "rpcPort": 56264,
      "trackingUrl": "http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0001/",
      "originalTrackingUrl": "http://d-69-91-129-173.dhcp4.washington.edu:19888/jobhistory/job/job_1430424020775_0001",
      "diagnosticsInfo": "",
      "appAttemptState": "FINISHED",
      "amContainerId": "container_1430424020775_0001_01_000001"
    }


#### XML response

HTTP Request:

    GET http://<timeline server http address:port>/ws/v1/applicationhistory/apps/application_1395789200506_0001/appattempts/appattempt_1395789200506_0001_000001
    Accept: application/xml

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/xml
    Content-Length: 488

Response Body:

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
    <appAttempt>
      <appAttemptId>appattempt_1430424020775_0001_000001</appAttemptId>
      <host>localhost</host>
      <rpcPort>56264</rpcPort>
      <trackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:8088/proxy/application_1430424020775_0001/</trackingUrl>
      <originalTrackingUrl>http://d-69-91-129-173.dhcp4.washington.edu:19888/jobhistory/job/job_1430424020775_0001</originalTrackingUrl>
      <diagnosticsInfo></diagnosticsInfo>
      <appAttemptState>FINISHED</appAttemptState>
      <amContainerId>container_1430424020775_0001_01_000001</amContainerId>
    </appAttempt>


## <a name="REST_API_CONTAINER_LIST"></a>Container List

With the Container List API, you can obtain a collection of resources, each
of which represents a container. When you run a GET operation on this
resource, you obtain a collection of container objects.

### URI:

Use the following URI to obtain all the container objects of an application
attempt identified by the `appid` value and the `appattemptid` value.

    http(s)://<timeline server http(s) address:port>/ws/v1/applicationhistory/apps/{appid}/appattempts/{appattemptid}/containers


### HTTP Operations Supported:

    GET

### Query Parameters Supported:

None

### Elements of the `containers` (Container List) Object

When you make a request for the list of containers, the information will be
returned as a collection of container objects. See also {{Container}} for
syntax of the container object.

| Item | Data Type   | Description |
|:---- |:---- |:---- |
| `container` | array of container objects(JSON)/zero or more container objects(XML) | The collection of container objects |

### Response Examples:

#### JSON response

HTTP Request:

    GET http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001/appattempts/appattempt_1430424020775_0001_000001/containers?

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:

    {
      "container": [
        {
          "containerId": "container_1430424020775_0001_01_000007",
          "allocatedMB": 1024,
          "allocatedVCores": 1,
          "assignedNodeId": "localhost:9105",
          "priority": 10,
          "startedTime": 1430424068296,
          "finishedTime": 1430424073006,
          "elapsedTime": 4710,
          "diagnosticsInfo": "Container killed by the ApplicationMaster.\nContainer killed on request. Exit code is 143\nContainer exited with a non-zero exit code 143\n",
          "logUrl": "http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000007/container_1430424020775_0001_01_000007/zshen",
          "containerExitStatus": -105,
          "containerState": "COMPLETE",
          "nodeHttpAddress": "http://localhost:8042"
        },
        {
          "containerId": "container_1430424020775_0001_01_000006",
          "allocatedMB": 1024,
          "allocatedVCores": 1,
          "assignedNodeId": "localhost:9105",
          "priority": 20,
          "startedTime": 1430424060317,
          "finishedTime": 1430424068293,
          "elapsedTime": 7976,
          "diagnosticsInfo": "Container killed by the ApplicationMaster.\nContainer killed on request. Exit code is 143\nContainer exited with a non-zero exit code 143\n",
          "logUrl": "http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000006/container_1430424020775_0001_01_000006/zshen",
          "containerExitStatus": -105,
          "containerState": "COMPLETE",
          "nodeHttpAddress": "http://localhost:8042"
        },
        {
          "containerId": "container_1430424020775_0001_01_000005",
          "allocatedMB": 1024,
          "allocatedVCores": 1,
          "assignedNodeId": "localhost:9105",
          "priority": 20,
          "startedTime": 1430424060316,
          "finishedTime": 1430424068294,
          "elapsedTime": 7978,
          "diagnosticsInfo": "Container killed by the ApplicationMaster.\nContainer killed on request. Exit code is 143\nContainer exited with a non-zero exit code 143\n",
          "logUrl": "http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000005/container_1430424020775_0001_01_000005/zshen",
          "containerExitStatus": -105,
          "containerState": "COMPLETE",
          "nodeHttpAddress": "http://localhost:8042"
        },
        {
          "containerId": "container_1430424020775_0001_01_000003",
          "allocatedMB": 1024,
          "allocatedVCores": 1,
          "assignedNodeId": "localhost:9105",
          "priority": 20,
          "startedTime": 1430424060315,
          "finishedTime": 1430424068289,
          "elapsedTime": 7974,
          "diagnosticsInfo": "Container killed by the ApplicationMaster.\nContainer killed on request. Exit code is 143\nContainer exited with a non-zero exit code 143\n",
          "logUrl": "http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000003/container_1430424020775_0001_01_000003/zshen",
          "containerExitStatus": -105,
          "containerState": "COMPLETE",
          "nodeHttpAddress": "http://localhost:8042"
        },
        {
          "containerId": "container_1430424020775_0001_01_000004",
          "allocatedMB": 1024,
          "allocatedVCores": 1,
          "assignedNodeId": "localhost:9105",
          "priority": 20,
          "startedTime": 1430424060315,
          "finishedTime": 1430424068291,
          "elapsedTime": 7976,
          "diagnosticsInfo": "Container killed by the ApplicationMaster.\nContainer killed on request. Exit code is 143\nContainer exited with a non-zero exit code 143\n",
          "logUrl": "http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000004/container_1430424020775_0001_01_000004/zshen",
          "containerExitStatus": -105,
          "containerState": "COMPLETE",
          "nodeHttpAddress": "http://localhost:8042"
        },
        {
          "containerId": "container_1430424020775_0001_01_000002",
          "allocatedMB": 1024,
          "allocatedVCores": 1,
          "assignedNodeId": "localhost:9105",
          "priority": 20,
          "startedTime": 1430424060313,
          "finishedTime": 1430424067250,
          "elapsedTime": 6937,
          "diagnosticsInfo": "Container killed by the ApplicationMaster.\nContainer killed on request. Exit code is 143\nContainer exited with a non-zero exit code 143\n",
          "logUrl": "http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000002/container_1430424020775_0001_01_000002/zshen",
          "containerExitStatus": -105,
          "containerState": "COMPLETE",
          "nodeHttpAddress": "http://localhost:8042"
        },
        {
          "containerId": "container_1430424020775_0001_01_000001",
          "allocatedMB": 2048,
          "allocatedVCores": 1,
          "assignedNodeId": "localhost:9105",
          "priority": 0,
          "startedTime": 1430424054314,
          "finishedTime": 1430424079022,
          "elapsedTime": 24708,
          "diagnosticsInfo": "",
          "logUrl": "http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000001/container_1430424020775_0001_01_000001/zshen",
          "containerExitStatus": 0,
          "containerState": "COMPLETE",
          "nodeHttpAddress": "http://localhost:8042"
        }
      ]
    }
    

#### XML response

HTTP Request:

    GET http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001/appattempts/appattempt_1430424020775_0001_000001/containers
    Accept: application/xml

Response Header:

      HTTP/1.1 200 OK
      Content-Type: application/xml
      Content-Length: 1428

Response Body:

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
    <containers>
      <container>
        <containerId>container_1430424020775_0001_01_000007</containerId>
        <allocatedMB>1024</allocatedMB>
        <allocatedVCores>1</allocatedVCores>
        <assignedNodeId>localhost:9105</assignedNodeId>
        <priority>10</priority>
        <startedTime>1430424068296</startedTime>
        <finishedTime>1430424073006</finishedTime>
        <elapsedTime>4710</elapsedTime>
        <diagnosticsInfo>Container killed by the ApplicationMaster.
          Container killed on request. Exit code is 143
          Container exited with a non-zero exit code 143
        </diagnosticsInfo>
        <logUrl>http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000007/container_1430424020775_0001_01_000007/zshen</logUrl>
        <containerExitStatus>-105</containerExitStatus>
        <containerState>COMPLETE</containerState>
        <nodeHttpAddress>http://localhost:8042</nodeHttpAddress>
      </container>
      <container>
        <containerId>container_1430424020775_0001_01_000006</containerId>
        <allocatedMB>1024</allocatedMB>
        <allocatedVCores>1</allocatedVCores>
        <assignedNodeId>localhost:9105</assignedNodeId>
        <priority>20</priority>
        <startedTime>1430424060317</startedTime>
        <finishedTime>1430424068293</finishedTime>
        <elapsedTime>7976</elapsedTime>
        <diagnosticsInfo>Container killed by the ApplicationMaster.
          Container killed on request. Exit code is 143
          Container exited with a non-zero exit code 143
        </diagnosticsInfo>
        <logUrl>http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000006/container_1430424020775_0001_01_000006/zshen</logUrl>
        <containerExitStatus>-105</containerExitStatus>
        <containerState>COMPLETE</containerState>
        <nodeHttpAddress>http://localhost:8042</nodeHttpAddress>
      </container>
      <container>
        <containerId>container_1430424020775_0001_01_000005</containerId>
        <allocatedMB>1024</allocatedMB>
        <allocatedVCores>1</allocatedVCores>
        <assignedNodeId>localhost:9105</assignedNodeId>
        <priority>20</priority>
        <startedTime>1430424060316</startedTime>
        <finishedTime>1430424068294</finishedTime>
        <elapsedTime>7978</elapsedTime>
        <diagnosticsInfo>Container killed by the ApplicationMaster.
          Container killed on request. Exit code is 143
          Container exited with a non-zero exit code 143
        </diagnosticsInfo>
        <logUrl>http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000005/container_1430424020775_0001_01_000005/zshen</logUrl>
        <containerExitStatus>-105</containerExitStatus>
        <containerState>COMPLETE</containerState>
        <nodeHttpAddress>http://localhost:8042</nodeHttpAddress>
      </container>
      <container>
        <containerId>container_1430424020775_0001_01_000003</containerId>
        <allocatedMB>1024</allocatedMB>
        <allocatedVCores>1</allocatedVCores>
        <assignedNodeId>localhost:9105</assignedNodeId>
        <priority>20</priority>
        <startedTime>1430424060315</startedTime>
        <finishedTime>1430424068289</finishedTime>
        <elapsedTime>7974</elapsedTime>
        <diagnosticsInfo>Container killed by the ApplicationMaster.
          Container killed on request. Exit code is 143
          Container exited with a non-zero exit code 143
        </diagnosticsInfo>
        <logUrl>http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000003/container_1430424020775_0001_01_000003/zshen</logUrl>
        <containerExitStatus>-105</containerExitStatus>
        <containerState>COMPLETE</containerState>
        <nodeHttpAddress>http://localhost:8042</nodeHttpAddress>
      </container>
      <container>
        <containerId>container_1430424020775_0001_01_000004</containerId>
        <allocatedMB>1024</allocatedMB>
        <allocatedVCores>1</allocatedVCores>
        <assignedNodeId>localhost:9105</assignedNodeId>
        <priority>20</priority>
        <startedTime>1430424060315</startedTime>
        <finishedTime>1430424068291</finishedTime>
        <elapsedTime>7976</elapsedTime>
        <diagnosticsInfo>Container killed by the ApplicationMaster.
          Container killed on request. Exit code is 143
          Container exited with a non-zero exit code 143
        </diagnosticsInfo>
        <logUrl>http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000004/container_1430424020775_0001_01_000004/zshen</logUrl>
        <containerExitStatus>-105</containerExitStatus>
        <containerState>COMPLETE</containerState>
        <nodeHttpAddress>http://localhost:8042</nodeHttpAddress>
      </container>
      <container>
        <containerId>container_1430424020775_0001_01_000002</containerId>
        <allocatedMB>1024</allocatedMB>
        <allocatedVCores>1</allocatedVCores>
        <assignedNodeId>localhost:9105</assignedNodeId>
        <priority>20</priority>
        <startedTime>1430424060313</startedTime>
        <finishedTime>1430424067250</finishedTime>
        <elapsedTime>6937</elapsedTime>
        <diagnosticsInfo>Container killed by the ApplicationMaster.
          Container killed on request. Exit code is 143
          Container exited with a non-zero exit code 143
        </diagnosticsInfo>
        <logUrl>http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000002/container_1430424020775_0001_01_000002/zshen</logUrl>
        <containerExitStatus>-105</containerExitStatus>
        <containerState>COMPLETE</containerState>
        <nodeHttpAddress>http://localhost:8042</nodeHttpAddress>
      </container>
      <container>
        <containerId>container_1430424020775_0001_01_000001</containerId>
        <allocatedMB>2048</allocatedMB>
        <allocatedVCores>1</allocatedVCores>
        <assignedNodeId>localhost:9105</assignedNodeId>
        <priority>0</priority>
        <startedTime>1430424054314</startedTime>
        <finishedTime>1430424079022</finishedTime>
        <elapsedTime>24708</elapsedTime>
        <diagnosticsInfo></diagnosticsInfo>
        <logUrl>http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000001/container_1430424020775_0001_01_000001/zshen</logUrl>
        <containerExitStatus>0</containerExitStatus>
        <containerState>COMPLETE</containerState>
        <nodeHttpAddress>http://localhost:8042</nodeHttpAddress>
      </container>
    </containers>

## <a name="REST_API_CONTAINER"></a>Container

With the Container API, you can get a container resource contains information
about a particular container of an application attempt of an application that
was running on an YARN cluster.

### URI:

Use the following URI to obtain a container object identified by the `appid`
value, the `appattemptid` value and the `containerid` value.

    http(s)://<timeline server http(s) address:port>/ws/v1/applicationhistory/apps/{appid}/appattempts/{appattemptid}/containers/{containerid}

### HTTP Operations Supported:

   GET

### Query Parameters Supported:

None

### Elements of the `container` (Container) Object:


| Item | Data Type   | Description   |
|:---- |:---- |:---- |
| `containerId` | string  | The container Id |
| `containerState` | string | The container state according to the ResourceManager - valid values are members of the ContainerState enum: COMPLETE |
| `containerExitStatus` | int  | The container exit status |
| `logUrl` | string | The log URL that can be used to access the container aggregated log |
| `diagnosticsInfo` | string | Detailed diagnostics information |
| `startedTime` | long | The time in which container started (in ms since epoch) |
| `finishedTime` | long | The time in which the container finished (in ms since epoch) |
| `elapsedTime` | long | The elapsed time since the container started (in ms) |
| `allocatedMB` | int | The memory in MB allocated to the container |
| `allocatedVCores` | int | The virtual cores allocated to the container |
| `priority` | int  | The priority of the container |
| `assignedNodeId` | string | The assigned node host and port of the container |

### Response Examples:

#### JSON response

HTTP Request:

    GET http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001/appattempts/appattempt_1430424020775_0001_000001/containers/container_1430424020775_0001_01_000001

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/json
    Transfer-Encoding: chunked

Response Body:

    {
      "containerId": "container_1430424020775_0001_01_000001",
      "allocatedMB": 2048,
      "allocatedVCores": 1,
      "assignedNodeId": "localhost:9105",
      "priority": 0,
      "startedTime": 1430424054314,
      "finishedTime": 1430424079022,
      "elapsedTime": 24708,
      "diagnosticsInfo": "",
      "logUrl": "http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000001/container_1430424020775_0001_01_000001/zshen",
      "containerExitStatus": 0,
      "containerState": "COMPLETE",
      "nodeHttpAddress": "http://localhost:8042"
    }

#### XML response

HTTP Request:

    GET http://localhost:8188/ws/v1/applicationhistory/apps/application_1430424020775_0001/appattempts/appattempt_1430424020775_0001_000001/containers/container_1430424020775_0001_01_000001
    Accept: application/xml

Response Header:

    HTTP/1.1 200 OK
    Content-Type: application/xml
    Content-Length: 669

Response Body:

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
    <container>
      <containerId>container_1430424020775_0001_01_000001</containerId>
      <allocatedMB>2048</allocatedMB>
      <allocatedVCores>1</allocatedVCores>
      <assignedNodeId>localhost:9105</assignedNodeId>
      <priority>0</priority>
      <startedTime>1430424054314</startedTime>
      <finishedTime>1430424079022</finishedTime>
      <elapsedTime>24708</elapsedTime>
      <diagnosticsInfo></diagnosticsInfo>
      <logUrl>http://0.0.0.0:8188/applicationhistory/logs/localhost:9105/container_1430424020775_0001_01_000001/container_1430424020775_0001_01_000001/zshen</logUrl>
      <containerExitStatus>0</containerExitStatus>
      <containerState>COMPLETE</containerState>
      <nodeHttpAddress>http://localhost:8042</nodeHttpAddress>
    </container>
 
 
### Response Codes

1. Queries where a domain, entity type, entity ID or similar cannot be resolved result in
HTTP 404, "Not Found" responses.
1. Requests in which the path, parameters or values are invalid result in
Bad Request, 400, responses.
1. In a secure cluster, a 401, "Forbidden", response is generated
when attempting to perform operations to which the caller does
not have the sufficient rights. There is an exception to this when
querying some entities, such as Domains; here the API deliberately
downgrades permission-denied outcomes as empty and not-founds responses.
This hides details of other domains from an unauthorized caller.
1. If the content of timeline entity PUT operations is invalid,
this failure *will not* result in an HTTP error code being retured.
A status code of 200 will be returned —however, there will be an error code
in the list of failed entities for each entity which could not be added.
