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Users

List users

Get a list of users.

This function takes pagination parameters page and per_page to restrict the list of users.

For normal users

GET /users
[
  {
    "id": 1,
    "username": "john_smith",
    "name": "John Smith",
    "state": "active",
    "avatar_url": "http://localhost:3000/uploads/user/avatar/1/cd8.jpeg",
    "web_url": "http://localhost:3000/john_smith"
  },
  {
    "id": 2,
    "username": "jack_smith",
    "name": "Jack Smith",
    "state": "blocked",
    "avatar_url": "http://gravatar.com/../e32131cd8.jpeg",
    "web_url": "http://localhost:3000/jack_smith"
  }
]

In addition, you can filter users based on states eg. blocked, active This works only to filter users who are blocked or active. It does not support active=false or blocked=false.

GET /users?active=true
GET /users?blocked=true

For admins

GET /users
[
  {
    "id": 1,
    "username": "john_smith",
    "email": "john@example.com",
    "name": "John Smith",
    "state": "active",
    "avatar_url": "http://localhost:3000/uploads/user/avatar/1/index.jpg",
    "web_url": "http://localhost:3000/john_smith",
    "created_at": "2012-05-23T08:00:58Z",
    "is_admin": false,
    "bio": null,
    "location": null,
    "skype": "",
    "linkedin": "",
    "twitter": "",
    "website_url": "",
    "organization": "",
    "last_sign_in_at": "2012-06-01T11:41:01Z",
    "confirmed_at": "2012-05-23T09:05:22Z",
    "last_activity_on": "2012-05-23",
    "color_scheme_id": 2,
    "projects_limit": 100,
    "current_sign_in_at": "2012-06-02T06:36:55Z",
    "identities": [
      {"provider": "github", "extern_uid": "2435223452345"},
      {"provider": "bitbucket", "extern_uid": "john.smith"},
      {"provider": "google_oauth2", "extern_uid": "8776128412476123468721346"}
    ],
    "can_create_group": true,
    "can_create_project": true,
    "two_factor_enabled": true,
    "external": false
  },
  {
    "id": 2,
    "username": "jack_smith",
    "email": "jack@example.com",
    "name": "Jack Smith",
    "state": "blocked",
    "avatar_url": "http://localhost:3000/uploads/user/avatar/2/index.jpg",
    "web_url": "http://localhost:3000/jack_smith",
    "created_at": "2012-05-23T08:01:01Z",
    "is_admin": false,
    "bio": null,
    "location": null,
    "skype": "",
    "linkedin": "",
    "twitter": "",
    "website_url": "",
    "organization": "",
    "last_sign_in_at": null,
    "confirmed_at": "2012-05-30T16:53:06.148Z",
    "last_activity_on": "2012-05-23",
    "color_scheme_id": 3,
    "projects_limit": 100,
    "current_sign_in_at": "2014-03-19T17:54:13Z",
    "identities": [],
    "can_create_group": true,
    "can_create_project": true,
    "two_factor_enabled": true,
    "external": false
  }
]

You can search for users by email or username with: /users?search=John

In addition, you can lookup users by username:

GET /users?username=:username

For example:

GET /users?username=jack_smith

You can search for users who are external with: /users?external=true

Single user

Get a single user.

For user

GET /users/:id

Parameters:

  • id (required) - The ID of a user
{
  "id": 1,
  "username": "john_smith",
  "name": "John Smith",
  "state": "active",
  "avatar_url": "http://localhost:3000/uploads/user/avatar/1/cd8.jpeg",
  "web_url": "http://localhost:3000/john_smith",
  "created_at": "2012-05-23T08:00:58Z",
  "is_admin": false,
  "bio": null,
  "location": null,
  "skype": "",
  "linkedin": "",
  "twitter": "",
  "website_url": "",
  "organization": ""
}

For admin

GET /users/:id

Parameters:

  • id (required) - The ID of a user
{
  "id": 1,
  "username": "john_smith",
  "email": "john@example.com",
  "name": "John Smith",
  "state": "active",
  "avatar_url": "http://localhost:3000/uploads/user/avatar/1/index.jpg",
  "web_url": "http://localhost:3000/john_smith",
  "created_at": "2012-05-23T08:00:58Z",
  "is_admin": false,
  "bio": null,
  "location": null,
  "skype": "",
  "linkedin": "",
  "twitter": "",
  "website_url": "",
  "organization": "",
  "last_sign_in_at": "2012-06-01T11:41:01Z",
  "confirmed_at": "2012-05-23T09:05:22Z",
  "last_activity_on": "2012-05-23",
  "color_scheme_id": 2,
  "projects_limit": 100,
  "current_sign_in_at": "2012-06-02T06:36:55Z",
  "identities": [
    {"provider": "github", "extern_uid": "2435223452345"},
    {"provider": "bitbucket", "extern_uid": "john.smith"},
    {"provider": "google_oauth2", "extern_uid": "8776128412476123468721346"}
  ],
  "can_create_group": true,
  "can_create_project": true,
  "two_factor_enabled": true,
  "external": false
}

User creation

Creates a new user. Note only administrators can create new users. Either password or reset_password should be specified (reset_password takes priority).

POST /users

Parameters:

  • email (required) - Email
  • password (optional) - Password
  • reset_password (optional) - Send user password reset link - true or false(default)
  • username (required) - Username
  • name (required) - Name
  • skype (optional) - Skype ID
  • linkedin (optional) - LinkedIn
  • twitter (optional) - Twitter account
  • website_url (optional) - Website URL
  • organization (optional) - Organization name
  • projects_limit (optional) - Number of projects user can create
  • extern_uid (optional) - External UID
  • provider (optional) - External provider name
  • bio (optional) - User's biography
  • location (optional) - User's location
  • admin (optional) - User is admin - true or false (default)
  • can_create_group (optional) - User can create groups - true or false
  • confirm (optional) - Require confirmation - true (default) or false
  • external (optional) - Flags the user as external - true or false(default)

User modification

Modifies an existing user. Only administrators can change attributes of a user.

PUT /users/:id

Parameters:

  • email - Email
  • username - Username
  • name - Name
  • password - Password
  • skype - Skype ID
  • linkedin - LinkedIn
  • twitter - Twitter account
  • website_url - Website URL
  • organization - Organization name
  • projects_limit - Limit projects each user can create
  • extern_uid - External UID
  • provider - External provider name
  • bio - User's biography
  • location (optional) - User's location
  • admin (optional) - User is admin - true or false (default)
  • can_create_group (optional) - User can create groups - true or false
  • external (optional) - Flags the user as external - true or false(default)

On password update, user will be forced to change it upon next login. Note, at the moment this method does only return a 404 error, even in cases where a 409 (Conflict) would be more appropriate, e.g. when renaming the email address to some existing one.

User deletion

Deletes a user. Available only for administrators. This is an idempotent function, calling this function for a non-existent user id still returns a status code 200 OK. The JSON response differs if the user was actually deleted or not. In the former the user is returned and in the latter not.

DELETE /users/:id

Parameters:

  • id (required) - The ID of the user

User

For normal users

Gets currently authenticated user.

GET /user
{
  "id": 1,
  "username": "john_smith",
  "email": "john@example.com",
  "name": "John Smith",
  "state": "active",
  "avatar_url": "http://localhost:3000/uploads/user/avatar/1/index.jpg",
  "web_url": "http://localhost:3000/john_smith",
  "created_at": "2012-05-23T08:00:58Z",
  "is_admin": false,
  "bio": null,
  "location": null,
  "skype": "",
  "linkedin": "",
  "twitter": "",
  "website_url": "",
  "organization": "",
  "last_sign_in_at": "2012-06-01T11:41:01Z",
  "confirmed_at": "2012-05-23T09:05:22Z",
  "last_activity_on": "2012-05-23",
  "color_scheme_id": 2,
  "projects_limit": 100,
  "current_sign_in_at": "2012-06-02T06:36:55Z",
  "identities": [
    {"provider": "github", "extern_uid": "2435223452345"},
    {"provider": "bitbucket", "extern_uid": "john_smith"},
    {"provider": "google_oauth2", "extern_uid": "8776128412476123468721346"}
  ],
  "can_create_group": true,
  "can_create_project": true,
  "two_factor_enabled": true,
  "external": false
}

For admins

Parameters:

  • sudo (required) - the ID of a user
GET /user
{
  "id": 1,
  "username": "john_smith",
  "email": "john@example.com",
  "name": "John Smith",
  "state": "active",
  "avatar_url": "http://localhost:3000/uploads/user/avatar/1/index.jpg",
  "web_url": "http://localhost:3000/john_smith",
  "created_at": "2012-05-23T08:00:58Z",
  "is_admin": false,
  "bio": null,
  "location": null,
  "skype": "",
  "linkedin": "",
  "twitter": "",
  "website_url": "",
  "organization": "",
  "last_sign_in_at": "2012-06-01T11:41:01Z",
  "confirmed_at": "2012-05-23T09:05:22Z",
  "last_activity_on": "2012-05-23",
  "color_scheme_id": 2,
  "projects_limit": 100,
  "current_sign_in_at": "2012-06-02T06:36:55Z",
  "identities": [
    {"provider": "github", "extern_uid": "2435223452345"},
    {"provider": "bitbucket", "extern_uid": "john_smith"},
    {"provider": "google_oauth2", "extern_uid": "8776128412476123468721346"}
  ],
  "can_create_group": true,
  "can_create_project": true,
  "two_factor_enabled": true,
  "external": false,
  "private_token": "dd34asd13as"
}

List SSH keys

Get a list of currently authenticated user's SSH keys.

GET /user/keys
[
  {
    "id": 1,
    "title": "Public key",
    "key": "ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAIEAiPWx6WM4lhHNedGfBpPJNPpZ7yKu+dnn1SJejgt4596k6YjzGGphH2TUxwKzxcKDKKezwkpfnxPkSMkuEspGRt/aZZ9wa++Oi7Qkr8prgHc4soW6NUlfDzpvZK2H5E7eQaSeP3SAwGmQKUFHCddNaP0L+hM7zhFNzjFvpaMgJw0=",
    "created_at": "2014-08-01T14:47:39.080Z"
  },
  {
    "id": 3,
    "title": "Another Public key",
    "key": "ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAIEAiPWx6WM4lhHNedGfBpPJNPpZ7yKu+dnn1SJejgt4596k6YjzGGphH2TUxwKzxcKDKKezwkpfnxPkSMkuEspGRt/aZZ9wa++Oi7Qkr8prgHc4soW6NUlfDzpvZK2H5E7eQaSeP3SAwGmQKUFHCddNaP0L+hM7zhFNzjFvpaMgJw0=",
    "created_at": "2014-08-01T14:47:39.080Z"
  }
]

Parameters:

  • none

List SSH keys for user

Get a list of a specified user's SSH keys. Available only for admin

GET /users/:id/keys

Parameters:

  • id (required) - id of specified user

Single SSH key

Get a single key.

GET /user/keys/:key_id

Parameters:

  • key_id (required) - The ID of an SSH key
{
  "id": 1,
  "title": "Public key",
  "key": "ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAIEAiPWx6WM4lhHNedGfBpPJNPpZ7yKu+dnn1SJejgt4596k6YjzGGphH2TUxwKzxcKDKKezwkpfnxPkSMkuEspGRt/aZZ9wa++Oi7Qkr8prgHc4soW6NUlfDzpvZK2H5E7eQaSeP3SAwGmQKUFHCddNaP0L+hM7zhFNzjFvpaMgJw0=",
  "created_at": "2014-08-01T14:47:39.080Z"
}

Add SSH key

Creates a new key owned by the currently authenticated user.

POST /user/keys

Parameters:

  • title (required) - new SSH Key's title
  • key (required) - new SSH key
{
  "created_at": "2015-01-21T17:44:33.512Z",
  "key": "ssh-dss AAAAB3NzaC1kc3MAAACBAMLrhYgI3atfrSD6KDas1b/3n6R/HP+bLaHHX6oh+L1vg31mdUqK0Ac/NjZoQunavoyzqdPYhFz9zzOezCrZKjuJDS3NRK9rspvjgM0xYR4d47oNZbdZbwkI4cTv/gcMlquRy0OvpfIvJtjtaJWMwTLtM5VhRusRuUlpH99UUVeXAAAAFQCVyX+92hBEjInEKL0v13c/egDCTQAAAIEAvFdWGq0ccOPbw4f/F8LpZqvWDydAcpXHV3thwb7WkFfppvm4SZte0zds1FJ+Hr8Xzzc5zMHe6J4Nlay/rP4ewmIW7iFKNBEYb/yWa+ceLrs+TfR672TaAgO6o7iSRofEq5YLdwgrwkMmIawa21FrZ2D9SPao/IwvENzk/xcHu7YAAACAQFXQH6HQnxOrw4dqf0NqeKy1tfIPxYYUZhPJfo9O0AmBW2S36pD2l14kS89fvz6Y1g8gN/FwFnRncMzlLY/hX70FSc/3hKBSbH6C6j8hwlgFKfizav21eS358JJz93leOakJZnGb8XlWvz1UJbwCsnR2VEY8Dz90uIk1l/UqHkA= loic@call",
  "title": "ABC",
  "id": 4
}

Will return created key with status 201 Created on success. If an error occurs a 400 Bad Request is returned with a message explaining the error:

{
  "message": {
    "fingerprint": [
      "has already been taken"
    ],
    "key": [
      "has already been taken"
    ]
  }
}

Add SSH key for user

Create new key owned by specified user. Available only for admin

POST /users/:id/keys

Parameters:

  • id (required) - id of specified user
  • title (required) - new SSH Key's title
  • key (required) - new SSH key

Delete SSH key for current user

Deletes key owned by currently authenticated user. This is an idempotent function and calling it on a key that is already deleted or not available results in 200 OK.

DELETE /user/keys/:key_id

Parameters:

  • key_id (required) - SSH key ID

Delete SSH key for given user

Deletes key owned by a specified user. Available only for admin.

DELETE /users/:id/keys/:key_id

Parameters:

  • id (required) - id of specified user
  • key_id (required) - SSH key ID

Will return 200 OK on success, or 404 Not found if either user or key cannot be found.

List emails

Get a list of currently authenticated user's emails.

GET /user/emails
[
  {
    "id": 1,
    "email": "email@example.com"
  },
  {
    "id": 3,
    "email": "email2@example.com"
  }
]

Parameters:

  • none

List emails for user

Get a list of a specified user's emails. Available only for admin

GET /users/:id/emails

Parameters:

  • id (required) - id of specified user

Single email

Get a single email.

GET /user/emails/:email_id

Parameters:

  • email_id (required) - email ID
{
  "id": 1,
  "email": "email@example.com"
}

Add email

Creates a new email owned by the currently authenticated user.

POST /user/emails

Parameters:

  • email (required) - email address
{
  "id": 4,
  "email": "email@example.com"
}

Will return created email with status 201 Created on success. If an error occurs a 400 Bad Request is returned with a message explaining the error:

{
  "message": {
    "email": [
      "has already been taken"
    ]
  }
}

Add email for user

Create new email owned by specified user. Available only for admin

POST /users/:id/emails

Parameters:

  • id (required) - id of specified user
  • email (required) - email address

Delete email for current user

Deletes email owned by currently authenticated user. This is an idempotent function and calling it on a email that is already deleted or not available results in 200 OK.

DELETE /user/emails/:email_id

Parameters:

  • email_id (required) - email ID

Delete email for given user

Deletes email owned by a specified user. Available only for admin.

DELETE /users/:id/emails/:email_id

Parameters:

  • id (required) - id of specified user
  • email_id (required) - email ID

Will return 200 OK on success, or 404 Not found if either user or email cannot be found.

Block user

Blocks the specified user. Available only for admin.

POST /users/:id/block

Parameters:

  • id (required) - id of specified user

Will return 201 OK on success, 404 User Not Found is user cannot be found or 403 Forbidden when trying to block an already blocked user by LDAP synchronization.

Unblock user

Unblocks the specified user. Available only for admin.

POST /users/:id/unblock

Parameters:

  • id (required) - id of specified user

Will return 201 OK on success, 404 User Not Found is user cannot be found or 403 Forbidden when trying to unblock a user blocked by LDAP synchronization.

Get user contribution events

Get the contribution events for the specified user, sorted from newest to oldest.

GET /users/:id/events

Parameters:

Attribute Type Required Description
id integer yes The ID of the user 
curl --header "PRIVATE-TOKEN: 9koXpg98eAheJpvBs5tK" https://gitlab.example.com/api/v4/users/:id/events

Example response:

[
  {
    "title": null,
    "project_id": 15,
    "action_name": "closed",
    "target_id": 830,
    "target_type": "Issue",
    "author_id": 1,
    "data": null,
    "target_title": "Public project search field",
    "author": {
      "name": "Dmitriy Zaporozhets",
      "username": "root",
      "id": 1,
      "state": "active",
      "avatar_url": "http://localhost:3000/uploads/user/avatar/1/fox_avatar.png",
      "web_url": "http://localhost:3000/root"
    },
    "author_username": "root"
  },
  {
    "title": null,
    "project_id": 15,
    "action_name": "opened",
    "target_id": null,
    "target_type": null,
    "author_id": 1,
    "author": {
      "name": "Dmitriy Zaporozhets",
      "username": "root",
      "id": 1,
      "state": "active",
      "avatar_url": "http://localhost:3000/uploads/user/avatar/1/fox_avatar.png",
      "web_url": "http://localhost:3000/root"
    },
    "author_username": "john",
    "data": {
      "before": "50d4420237a9de7be1304607147aec22e4a14af7",
      "after": "c5feabde2d8cd023215af4d2ceeb7a64839fc428",
      "ref": "refs/heads/master",
      "user_id": 1,
      "user_name": "Dmitriy Zaporozhets",
      "repository": {
        "name": "gitlabhq",
        "url": "git@dev.gitlab.org:gitlab/gitlabhq.git",
        "description": "GitLab: self hosted Git management software. \r\nDistributed under the MIT License.",
        "homepage": "https://dev.gitlab.org/gitlab/gitlabhq"
      },
      "commits": [
        {
          "id": "c5feabde2d8cd023215af4d2ceeb7a64839fc428",
          "message": "Add simple search to projects in public area",
          "timestamp": "2013-05-13T18:18:08+00:00",
          "url": "https://dev.gitlab.org/gitlab/gitlabhq/commit/c5feabde2d8cd023215af4d2ceeb7a64839fc428",
          "author": {
            "name": "Dmitriy Zaporozhets",
            "email": "dmitriy.zaporozhets@gmail.com"
          }
        }
      ],
      "total_commits_count": 1
    },
    "target_title": null
  },
  {
    "title": null,
    "project_id": 15,
    "action_name": "closed",
    "target_id": 840,
    "target_type": "Issue",
    "author_id": 1,
    "data": null,
    "target_title": "Finish & merge Code search PR",
    "author": {
      "name": "Dmitriy Zaporozhets",
      "username": "root",
      "id": 1,
      "state": "active",
      "avatar_url": "http://localhost:3000/uploads/user/avatar/1/fox_avatar.png",
      "web_url": "http://localhost:3000/root"
    },
    "author_username": "root"
  },
  {
    "title": null,
    "project_id": 15,
    "action_name": "commented on",
    "target_id": 1312,
    "target_type": "Note",
    "author_id": 1,
    "data": null,
    "target_title": null,
    "created_at": "2015-12-04T10:33:58.089Z",
    "note": {
      "id": 1312,
      "body": "What an awesome day!",
      "attachment": null,
      "author": {
        "name": "Dmitriy Zaporozhets",
        "username": "root",
        "id": 1,
        "state": "active",
        "avatar_url": "http://localhost:3000/uploads/user/avatar/1/fox_avatar.png",
        "web_url": "http://localhost:3000/root"
      },
      "created_at": "2015-12-04T10:33:56.698Z",
      "system": false,
      "noteable_id": 377,
      "noteable_type": "Issue"
    },
    "author": {
      "name": "Dmitriy Zaporozhets",
      "username": "root",
      "id": 1,
      "state": "active",
      "avatar_url": "http://localhost:3000/uploads/user/avatar/1/fox_avatar.png",
      "web_url": "http://localhost:3000/root"
    },
    "author_username": "root"
  }
]

Get all impersonation tokens of a user

Requires admin permissions.

It retrieves every impersonation token of the user. Use the pagination parameters page and per_page to restrict the list of impersonation tokens.

GET /users/:user_id/impersonation_tokens

Parameters:

Attribute Type Required Description
user_id integer yes The ID of the user
state string no filter tokens based on state (all, active, inactive) 
curl --header "PRIVATE-TOKEN: 9koXpg98eAheJpvBs5tK" https://gitlab.example.com/api/v4/users/42/impersonation_tokens

Example response:

[
   {
      "active" : true,
      "token" : "EsMo-vhKfXGwX9RKrwiy",
      "scopes" : [
         "api"
      ],
      "revoked" : false,
      "name" : "mytoken",
      "id" : 2,
      "created_at" : "2017-03-17T17:18:09.283Z",
      "impersonation" : true,
      "expires_at" : "2017-04-04"
   },
   {
      "active" : false,
      "scopes" : [
         "read_user"
      ],
      "revoked" : true,
      "token" : "ZcZRpLeEuQRprkRjYydY",
      "name" : "mytoken2",
      "created_at" : "2017-03-17T17:19:28.697Z",
      "id" : 3,
      "impersonation" : true,
      "expires_at" : "2017-04-14"
   }
]

Get an impersonation token of a user

Requires admin permissions.

It shows a user's impersonation token.

GET /users/:user_id/impersonation_tokens/:impersonation_token_id

Parameters:

Attribute Type Required Description
user_id integer yes The ID of the user
impersonation_token_id integer yes The ID of the impersonation token 
curl --header "PRIVATE-TOKEN: 9koXpg98eAheJpvBs5tK" https://gitlab.example.com/api/v4/users/42/impersonation_tokens/2

Example response:

{
   "active" : true,
   "token" : "EsMo-vhKfXGwX9RKrwiy",
   "scopes" : [
      "api"
   ],
   "revoked" : false,
   "name" : "mytoken",
   "id" : 2,
   "created_at" : "2017-03-17T17:18:09.283Z",
   "impersonation" : true,
   "expires_at" : "2017-04-04"
}

Create an impersonation token

Requires admin permissions.

It creates a new impersonation token. Note that only administrators can do this. You are only able to create impersonation tokens to impersonate the user and perform both API calls and Git reads and writes. The user will not see these tokens in his profile settings page.

POST /users/:user_id/impersonation_tokens

Parameters:

Attribute Type Required Description
user_id integer yes The ID of the user
name string yes The name of the impersonation token
expires_at date no The expiration date of the impersonation token in ISO format (YYYY-MM-DD)
scopes array yes The array of scopes of the impersonation token (api, read_user) 
curl --request POST --header "PRIVATE-TOKEN: 9koXpg98eAheJpvBs5tK" --data "name=mytoken" --data "expires_at=2017-04-04" --data "scopes[]=api" https://gitlab.example.com/api/v4/users/42/impersonation_tokens

Example response:

{
   "id" : 2,
   "revoked" : false,
   "scopes" : [
      "api"
   ],
   "token" : "EsMo-vhKfXGwX9RKrwiy",
   "active" : true,
   "impersonation" : true,
   "name" : "mytoken",
   "created_at" : "2017-03-17T17:18:09.283Z",
   "expires_at" : "2017-04-04"
}

Revoke an impersonation token

Requires admin permissions.

It revokes an impersonation token.

DELETE /users/:user_id/impersonation_tokens/:impersonation_token_id
curl --request DELETE --header "PRIVATE-TOKEN: 9koXpg98eAheJpvBs5tK" https://gitlab.example.com/api/v4/users/42/impersonation_tokens/1

Parameters:

Attribute Type Required Description
user_id integer yes The ID of the user
impersonation_token_id integer yes The ID of the impersonation token

Get user activities (admin only)

Note: This API endpoint is only available on 8.15 (EE) and 9.1 (CE) and above.

Get the last activity date for all users, sorted from oldest to newest.

The activities that update the timestamp are:

  • Git HTTP/SSH activities (such as clone, push)
  • User logging in into GitLab

By default, it shows the activity for all users in the last 6 months, but this can be amended by using the from parameter.

GET /user/activities

Parameters:

Attribute Type Required Description
from string no Date string in the format YEAR-MONTH-DAY, e.g. 2016-03-11. Defaults to 6 months ago. 
curl --header "PRIVATE-TOKEN: 9koXpg98eAheJpvBs5tK" https://gitlab.example.com/api/v4/user/activities

Example response:

[
  {
    "username": "user1",
    "last_activity_on": "2015-12-14",
    "last_activity_at": "2015-12-14"
  },
  {
    "username": "user2",
    "last_activity_on": "2015-12-15",
    "last_activity_at": "2015-12-15"
  },
  {
    "username": "user3",
    "last_activity_on": "2015-12-16",
    "last_activity_at": "2015-12-16"
  }
]

Please note that last_activity_at is deprecated, please use last_activity_on.