Hedera
Hedera topics API

The topics object represents the information associated with a topic entity and returns topic messages information.
Documentation GitHub OpenAPI
OpenAPI Specification

openapi: 3.1.0
info:
  title: Mirror Node REST accounts topics API
  version: 0.156.0
  license:
    name: Apache-2.0
    url: https://www.apache.org/licenses/LICENSE-2.0.html
  description: 'The REST API offers the ability to query transactions and entity information from a mirror node.


    Base url: [/api/v1](/api/v1)


    OpenAPI Spec: [/api/v1/docs/openapi.yml](/api/v1/docs/openapi.yml)'
  contact:
    name: Mirror Node Team
    email: mirrornode@hedera.com
    url: https://github.com/hiero-ledger/hiero-mirror-node
servers:
- description: The current REST API server
  url: ''
- description: The production REST API servers
  url: '{scheme}://{network}.mirrornode.hedera.com'
  variables:
    scheme:
      default: https
      description: The URI scheme
      enum:
      - http
      - https
    network:
      default: testnet
      description: The Hedera network in use
      enum:
      - mainnet-public
      - mainnet
      - previewnet
      - testnet
tags:
- name: topics
  description: The topics object represents the information associated with a topic entity and returns topic messages information.
  externalDocs:
    url: https://docs.hedera.com/guides/docs/mirror-node-api/cryptocurrency-api#topic-messages
paths:
  /api/v1/topics/{topicId}:
    get:
      summary: Get topic by ID
      description: Returns the topic details for the given topic ID.
      operationId: getTopic
      parameters:
      - $ref: '#/components/parameters/topicIdPathParam'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Topic'
        '400':
          $ref: '#/components/responses/InvalidParameterError'
        '404':
          $ref: '#/components/responses/NotFoundError'
      tags:
      - topics
  /api/v1/topics/{topicId}/messages:
    get:
      summary: List topic messages by id
      description: Returns the list of topic messages for the given topic id.
      operationId: getTopicMessages
      parameters:
      - $ref: '#/components/parameters/topicIdPathParam'
      - name: encoding
        in: query
        example: base64
        schema:
          type: string
      - $ref: '#/components/parameters/limitQueryParam'
      - $ref: '#/components/parameters/orderQueryParam'
      - name: sequencenumber
        in: query
        example: 2
        schema:
          format: int64
          minimum: 0
          type: integer
      - $ref: '#/components/parameters/timestampQueryParam'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TopicMessagesResponse'
        '400':
          $ref: '#/components/responses/InvalidParameterError'
        '404':
          $ref: '#/components/responses/TopicNotFound'
      tags:
      - topics
  /api/v1/topics/{topicId}/messages/{sequenceNumber}:
    get:
      summary: Get topic message by id and sequence number
      description: Returns a single topic message for the given topic id and sequence number.
      operationId: getTopicMessageByIdAndSequenceNumber
      parameters:
      - $ref: '#/components/parameters/topicIdPathParam'
      - name: sequenceNumber
        in: path
        required: true
        description: Topic message sequence number
        example: 2
        schema:
          format: int64
          minimum: 0
          type: integer
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TopicMessage'
        '400':
          $ref: '#/components/responses/InvalidParameterError'
        '404':
          $ref: '#/components/responses/NotFoundError'
      tags:
      - topics
  /api/v1/topics/messages/{timestamp}:
    get:
      summary: Get topic message by consensusTimestamp
      description: Returns a topic message the given the consensusTimestamp.
      operationId: getTopicMessageByTimestamp
      parameters:
      - $ref: '#/components/parameters/timestampPathParam'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TopicMessage'
        '400':
          $ref: '#/components/responses/InvalidParameterError'
        '404':
          $ref: '#/components/responses/NotFoundError'
      tags:
      - topics
components:
  schemas:
    FixedCustomFee:
      type: object
      properties:
        amount:
          example: 100
          format: int64
          type: integer
        collector_account_id:
          $ref: '#/components/schemas/EntityId'
        denominating_token_id:
          $ref: '#/components/schemas/EntityId'
    ChunkInfo:
      type:
      - object
      - 'null'
      properties:
        initial_transaction_id:
          $ref: '#/components/schemas/TransactionId'
        number:
          example: 1
          format: int32
          type: integer
        total:
          example: 2
          format: int32
          type: integer
    Key:
      description: The public key which controls access to various network entities.
      type:
      - object
      - 'null'
      properties:
        _type:
          type: string
          enum:
          - ECDSA_SECP256K1
          - ED25519
          - ProtobufEncoded
          example: ProtobufEncoded
        key:
          type: string
          example: 15706b229b3ba33d4a5a41ff54ce1cfe0a3d308672a33ff382f81583e02bd743
    TopicMessages:
      type: array
      items:
        $ref: '#/components/schemas/TopicMessage'
    TimestampRange:
      type: object
      description: A timestamp range an entity is valid for
      properties:
        from:
          allOf:
          - $ref: '#/components/schemas/Timestamp'
          - description: The inclusive from timestamp in seconds
        to:
          allOf:
          - $ref: '#/components/schemas/TimestampNullable'
          - description: The exclusive to timestamp in seconds
    TimestampNullable:
      description: A Unix timestamp in seconds.nanoseconds format
      type:
      - string
      - 'null'
      example: '1586567700.453054000'
      pattern: ^\d{1,10}(\.\d{1,9})?$
    TransactionId:
      type: object
      properties:
        account_id:
          $ref: '#/components/schemas/EntityId'
        nonce:
          example: 0
          format: int32
          type:
          - integer
          - 'null'
          minimum: 0
        scheduled:
          example: false
          type:
          - boolean
          - 'null'
        transaction_valid_start:
          $ref: '#/components/schemas/Timestamp'
    Links:
      type: object
      properties:
        next:
          example: null
          type:
          - string
          - 'null'
    EntityId:
      type:
      - string
      - 'null'
      description: Network entity ID in the format of `shard.realm.num`
      pattern: ^\d{1,10}\.\d{1,10}\.\d{1,10}$
      example: 0.0.2
    TopicMessage:
      type: object
      properties:
        chunk_info:
          $ref: '#/components/schemas/ChunkInfo'
        consensus_timestamp:
          $ref: '#/components/schemas/Timestamp'
        message:
          type: string
        payer_account_id:
          $ref: '#/components/schemas/EntityId'
        running_hash:
          type: string
          format: byte
        running_hash_version:
          format: int32
          type: integer
        sequence_number:
          format: int64
          type: integer
        topic_id:
          $ref: '#/components/schemas/EntityId'
      required:
      - consensus_timestamp
      - message
      - payer_account_id
      - running_hash
      - running_hash_version
      - sequence_number
      - topic_id
      example:
        chunk_info:
          initial_transaction_id: 0.0.10-1234567890-000000321
          nonce: 3
          number: 1
          total: 2
          scheduled: true
        consensus_timestamp: '1234567890.000000001'
        message: bWVzc2FnZQ==
        payer_account_id: 0.0.10
        running_hash: cnVubmluZ19oYXNo
        running_hash_version: 2
        sequence_number: 1
        topic_id: 0.0.7
    ConsensusCustomFees:
      description: Custom fees assessed for each message submitted to the topic
      type: object
      properties:
        created_timestamp:
          $ref: '#/components/schemas/Timestamp'
        fixed_fees:
          type: array
          items:
            $ref: '#/components/schemas/FixedCustomFee'
    Timestamp:
      description: A Unix timestamp in seconds.nanoseconds format
      type: string
      example: '1586567700.453054000'
      pattern: ^\d{1,10}(\.\d{1,9})?$
    TopicMessagesResponse:
      type: object
      properties:
        messages:
          $ref: '#/components/schemas/TopicMessages'
        links:
          $ref: '#/components/schemas/Links'
    Error:
      type: object
      properties:
        _status:
          type: object
          properties:
            messages:
              type: array
              items:
                type: object
                properties:
                  data:
                    description: Error message in hexadecimal
                    example: '0x3000'
                    format: binary
                    pattern: ^0x[0-9a-fA-F]+$
                    type:
                    - string
                    - 'null'
                  detail:
                    description: Detailed error message
                    example: Generic detailed error message
                    type:
                    - string
                    - 'null'
                  message:
                    description: Error message
                    example: Generic error message
                    type: string
    Topic:
      type: object
      properties:
        admin_key:
          $ref: '#/components/schemas/Key'
        auto_renew_account:
          $ref: '#/components/schemas/EntityId'
        auto_renew_period:
          description: The amount of time to attempt to extend the topic's lifetime after expiration.
          example: 7776000
          format: int64
          type:
          - integer
          - 'null'
        created_timestamp:
          $ref: '#/components/schemas/TimestampNullable'
        custom_fees:
          $ref: '#/components/schemas/ConsensusCustomFees'
        deleted:
          description: Whether the topic is deleted or not.
          example: false
          type:
          - boolean
          - 'null'
        fee_exempt_key_list:
          description: Keys permitted to submit messages to the topic without paying custom fees
          type: array
          items:
            $ref: '#/components/schemas/Key'
        fee_schedule_key:
          $ref: '#/components/schemas/Key'
        memo:
          description: The memo associated with the topic.
          example: topic memo
          type: string
        submit_key:
          $ref: '#/components/schemas/Key'
        timestamp:
          $ref: '#/components/schemas/TimestampRange'
        topic_id:
          $ref: '#/components/schemas/EntityId'
      required:
      - admin_key
      - auto_renew_account
      - auto_renew_period
      - created_timestamp
      - custom_fees
      - deleted
      - fee_exempt_key_list
      - fee_schedule_key
      - memo
      - submit_key
      - timestamp
      - topic_id
  responses:
    InvalidParameterError:
      description: Invalid parameter
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            _status:
              messages:
              - message: 'Invalid parameter: account.id'
              - message: Invalid Transaction id. Please use \shard.realm.num-sss-nnn\ format where sss are seconds and nnn are nanoseconds
    NotFoundError:
      description: Not Found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            _status:
              messages:
              - message: Not found
    TopicNotFound:
      description: Topic Not Found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            _status:
              messages:
              - message: No such topic id - 7
  parameters:
    topicIdPathParam:
      name: topicId
      in: path
      required: true
      description: Topic id
      schema:
        $ref: '#/components/schemas/EntityId'
    orderQueryParam:
      name: order
      in: query
      description: The order in which items are listed
      example: desc
      schema:
        enum:
        - asc
        - desc
        default: asc
    timestampPathParam:
      name: timestamp
      in: path
      description: The Unix timestamp in seconds.nanoseconds format, the timestamp at which the associated transaction reached consensus. See [unixtimestamp.com](https://www.unixtimestamp.com/) for a simple way to convert a date to the 'seconds' part of the Unix time.
      required: true
      example: 1234567890.0000007
      schema:
        type: string
        pattern: ^\d{1,10}(\.\d{1,9})?$
    limitQueryParam:
      name: limit
      in: query
      description: The maximum number of items to return
      example: 2
      schema:
        format: int32
        type: integer
        default: 25
        minimum: 1
        maximum: 100
    timestampQueryParam:
      description: The consensus timestamp as a Unix timestamp in seconds.nanoseconds format with an optional comparison operator. See [unixtimestamp.com](https://www.unixtimestamp.com/) for a simple way to convert a date to the 'seconds' part of the Unix time.
      name: timestamp
      in: query
      explode: true
      examples:
        noValue:
          summary: --
          value: ''
        secondsNoOperator:
          summary: Example of seconds equals with no operator
          value: 1234567890
        timestampNoOperator:
          summary: Example of timestamp equals with no operator
          value: 1234567890
        secondsEqOperator:
          summary: Example of seconds equals with operator
          value: eq:1234567890
        timestampEqOperator:
          summary: Example of timestamp equals with operator
          value: eq:1234567890.000000200
        secondsNeOperator:
          summary: Example of seconds not equals operator
          value: ne:1234567890
        timestampNeOperator:
          summary: Example of timestamp not equals operator
          value: ne:1234567890.000000300
        secondsGtOperator:
          summary: Example of seconds greater than operator
          value: gt:1234567890
        timestampGtOperator:
          summary: Example of timestamp greater than operator
          value: gt:1234567890.000000400
        secondsGteOperator:
          summary: Example of seconds greater than or equals operator
          value: gte:1234567890
        timestampGteOperator:
          summary: Example of timestamp greater than or equals operator
          value: gte:1234567890.000000500
        secondsLtOperator:
          summary: Example of seconds less than operator
          value: lt:1234567890
        timestampLtOperator:
          summary: Example of timestamp less than operator
          value: lt:1234567890.000000600
        secondsLteOperator:
          summary: Example of seconds less than or equals operator
          value: lte:1234567890
        timestampLteOperator:
          summary: Example of timestamp less than or equals operator
          value: lte:1234567890.000000700
      schema:
        type: array
        items:
          type: string
          pattern: ^((eq|gt|gte|lt|lte|ne):)?\d{1,10}(\.\d{1,9})?$
externalDocs:
  description: REST API Docs
  url: https://docs.hedera.com/guides/docs/mirror-node-api/cryptocurrency-api
Hedera topics API

Documentation

Specifications

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OpenAPI Specification
