openapi: 3.1.0
info:
  title: Viva Engage (Yammer) Legacy REST API
  description: |
    Legacy Viva Engage (Yammer) REST API for messages, threads, topics, groups, users,
    subscriptions, and search. Sourced from
    https://learn.microsoft.com/en-us/rest/api/yammer/. Only v1 endpoints are supported.
    Authentication uses Yammer OAuth 2.0 legacy tokens or Microsoft Entra tokens
    (delegated access only).
  version: '1.0'
  contact:
    name: Viva Engage (Yammer) API
    url: https://learn.microsoft.com/en-us/rest/api/yammer/
servers:
  - url: https://www.yammer.com/api/v1
    description: Yammer Core REST API v1
security:
  - OAuth2: []
paths:
  /messages/my_feed.json:
    get:
      summary: Get current user's feed messages
      operationId: getMyFeed
      tags: [Messages]
      responses:
        '200':
          description: Messages
  /messages/algo.json:
    get:
      summary: Get algorithmically sorted messages
      operationId: getAlgoMessages
      tags: [Messages]
      responses:
        '200':
          description: Messages
  /messages/following.json:
    get:
      summary: Get messages from followed users
      operationId: getFollowingMessages
      tags: [Messages]
      responses:
        '200':
          description: Messages
  /messages.json:
    get:
      summary: Get messages from user's network feed
      operationId: listMessages
      tags: [Messages]
      responses:
        '200':
          description: Messages
    post:
      summary: Post a new message
      operationId: postMessage
      tags: [Messages]
      requestBody:
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                body: { type: string }
                group_id: { type: integer }
                replied_to_id: { type: integer }
                direct_to_id: { type: integer }
                topic1: { type: string }
      responses:
        '201':
          description: Created
  /messages/sent.json:
    get:
      summary: Get messages sent by the current user
      operationId: getSentMessages
      tags: [Messages]
      responses:
        '200':
          description: Messages
  /messages/private.json:
    get:
      summary: Get private messages received by current user
      operationId: getPrivateMessages
      tags: [Messages]
      responses:
        '200':
          description: Messages
  /messages/received.json:
    get:
      summary: Get messages received by current user
      operationId: getReceivedMessages
      tags: [Messages]
      responses:
        '200':
          description: Messages
  /messages/in_thread/{thread_id}.json:
    get:
      summary: Get messages in a thread
      operationId: getMessagesInThread
      tags: [Messages]
      parameters:
        - name: thread_id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: Messages
  /messages/in_group/{group_id}.json:
    get:
      summary: Get messages in a group
      operationId: getMessagesInGroup
      tags: [Messages]
      parameters:
        - name: group_id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: Messages
  /messages/about_topic/{id}.json:
    get:
      summary: Get messages about a topic
      operationId: getMessagesAboutTopic
      tags: [Messages]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: Messages
  /messages/liked_by/current.json:
    post:
      summary: Like a message
      operationId: likeMessage
      tags: [Messages]
      parameters:
        - name: message_id
          in: query
          required: true
          schema: { type: integer }
      responses:
        '201':
          description: Liked
    delete:
      summary: Unlike a message
      operationId: unlikeMessage
      tags: [Messages]
      parameters:
        - name: message_id
          in: query
          required: true
          schema: { type: integer }
      responses:
        '204':
          description: Unliked
  /messages/{id}.json:
    delete:
      summary: Delete a message
      operationId: deleteMessage
      tags: [Messages]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '204':
          description: Deleted
  /uploaded_files/{id}.json:
    delete:
      summary: Delete an uploaded file
      operationId: deleteUploadedFile
      tags: [Files]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '204':
          description: Deleted
  /threads/{id}.json:
    get:
      summary: Get thread details
      operationId: getThread
      tags: [Threads]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: Thread
  /topics/{id}.json:
    get:
      summary: Get topic details
      operationId: getTopic
      tags: [Topics]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: Topic
  /group_memberships.json:
    post:
      summary: Add a user to a group
      operationId: addGroupMembership
      tags: [Groups]
      parameters:
        - name: group_id
          in: query
          required: true
          schema: { type: integer }
      responses:
        '201':
          description: Added
    delete:
      summary: Remove a user from a group
      operationId: removeGroupMembership
      tags: [Groups]
      parameters:
        - name: group_id
          in: query
          required: true
          schema: { type: integer }
      responses:
        '204':
          description: Removed
  /groups/for_user/{user_id}.json:
    get:
      summary: Get groups for a user
      operationId: getGroupsForUser
      tags: [Groups]
      parameters:
        - name: user_id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: Groups
  /users.json:
    get:
      summary: List users
      operationId: listUsers
      tags: [Users]
      responses:
        '200':
          description: Users
    post:
      summary: Create a new user
      operationId: createUser
      tags: [Users]
      requestBody:
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                email: { type: string }
                full_name: { type: string }
      responses:
        '201':
          description: Created
  /users/current.json:
    get:
      summary: Get current user profile
      operationId: getCurrentUser
      tags: [Users]
      responses:
        '200':
          description: User
  /users/{id}.json:
    get:
      summary: Get a user profile by id
      operationId: getUser
      tags: [Users]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: User
    put:
      summary: Update a user's profile
      operationId: updateUser
      tags: [Users]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      requestBody:
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              type: object
      responses:
        '200':
          description: Updated
    delete:
      summary: Delete a user
      operationId: deleteUser
      tags: [Users]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '204':
          description: Deleted
  /users/by_email.json:
    get:
      summary: Get user profile by email
      operationId: getUserByEmail
      tags: [Users]
      parameters:
        - name: email
          in: query
          required: true
          schema: { type: string, format: email }
      responses:
        '200':
          description: User
  /users/in_group/{id}.json:
    get:
      summary: Get users in a group
      operationId: getUsersInGroup
      tags: [Users]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: Users
  /subscriptions/to_topic/{id}.json:
    get:
      summary: Get subscriptions to a topic
      operationId: getTopicSubscriptions
      tags: [Subscriptions]
      parameters:
        - name: id
          in: path
          required: true
          schema: { type: integer }
      responses:
        '200':
          description: Subscriptions
  /subscriptions:
    post:
      summary: Subscribe to a topic or user
      operationId: createSubscription
      tags: [Subscriptions]
      responses:
        '201':
          description: Subscribed
    delete:
      summary: Unsubscribe from a topic or user
      operationId: deleteSubscription
      tags: [Subscriptions]
      responses:
        '204':
          description: Unsubscribed
  /search.json:
    get:
      summary: Search messages, users, and topics
      operationId: search
      tags: [Search]
      parameters:
        - name: search
          in: query
          required: true
          schema: { type: string }
      responses:
        '200':
          description: Results
  /networks/current.json:
    get:
      summary: Get current network details
      operationId: getCurrentNetwork
      tags: [Networks]
      responses:
        '200':
          description: Network
components:
  securitySchemes:
    OAuth2:
      type: oauth2
      description: |
        Yammer OAuth 2.0 legacy tokens or Microsoft Entra tokens. Delegated access only.
      flows:
        authorizationCode:
          authorizationUrl: https://www.yammer.com/dialog/oauth
          tokenUrl: https://www.yammer.com/oauth2/access_token.json
          scopes: {}