---
openapi: 3.0.1

info:
  title: mod_rest API
  version: 0.3.2
  description: |
    API for sending and receiving stanzas, in a REST-ish fashion or by
    responding to webhooks. Multiple formats supported, including native XML
    and a simplified JSON mapping.
  license:
    name: MIT

paths:

  /rest:
    post:
      summary: Send stanzas and receive responses. Webhooks work the same way.
      tags:
      - generic
      security:
        - basic: []
        - token: []
      requestBody:
        $ref: '#/components/requestBodies/common'
      responses:
        '200':
          $ref: '#/components/responses/success'
        '202':
          $ref: '#/components/responses/sent'

  /rest/{kind}/{type}/{to}:
    post:
      summary: Even more RESTful mapping with certain components in the path.
      tags:
      - generic
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/kind'
      - $ref: '#/components/parameters/type'
      - $ref: '#/components/parameters/to'
      requestBody:
        $ref: '#/components/requestBodies/common'
      responses:
        '200':
          $ref: '#/components/responses/success'

  /rest/echo:
    post:
      summary: Build as stanza and return it for inspection.
      tags:
      - debug
      security:
        - basic: []
        - token: []
      requestBody:
        $ref: '#/components/requestBodies/common'
      responses:
        '200':
          $ref: '#/components/responses/success'

  /rest/ping/{to}:
    get:
      tags:
      - query
      summary: Ping a local or remote server or other entity
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      responses:
        '200':
          description: Test reachability of some address
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/iq_pong'
            application/xmpp+xml:
              schema:
                $ref: '#/components/schemas/iq_pong'


  /rest/version/{to}:
    get:
      tags:
      - query
      summary: Ask what software version is used.
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      responses:
        '200':
          description: Version query response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/iq_result_version'
            application/xmpp+xml:
              schema:
                $ref: '#/components/schemas/iq_result_version'

  /rest/disco/{to}:
    get:
      tags:
      - query
      summary: Query a remote entity for supported features
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      responses:
        '200':
          $ref: '#/components/responses/success'

  /rest/items/{to}:
    get:
      tags:
      - query
      summary: Query an entity for related services, chat rooms or other items
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      responses:
        '200':
          $ref: '#/components/responses/success'

  /rest/extdisco/{to}:
    get:
      tags:
      - query
      summary: Query for external services (usually STUN and TURN)
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      - name: type
        in: query
        schema:
          type: string
          example: stun
      responses:
        '200':
          $ref: '#/components/responses/success'


  /rest/archive/{to}:
    get:
      tags:
      - query
      summary: Query a message archive
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      - name: with
        in: query
        schema:
          type: string
      - name: start
        in: query
        schema:
          type: string
      - name: end
        in: query
        schema:
          type: string
      - name: before-id
        in: query
        schema:
          type: string
      - name: after-id
        in: query
        schema:
          type: string
      - name: ids
        in: query
        schema:
          type: string
        description: comma-separated list of archive ids
      - name: after
        in: query
        schema:
          type: string
      - name: before
        in: query
        schema:
          type: string
      - name: max
        in: query
        schema:
          type: integer
      responses:
        '200':
          $ref: '#/components/responses/success'

  /rest/lastactivity/{to}:
    get:
      tags:
      - query
      summary: Query last activity of an entity. Sometimes used as "uptime" for servers.
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      responses:
        '200':
          $ref: '#/components/responses/success'

  /rest/stats/{to}:
    get:
      tags:
      - query
      summary: Query an entity for statistics
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      responses:
        '200':
          $ref: '#/components/responses/success'

  /rest/upload_request/{to}:
    get:
      tags:
      - query
      summary: Lorem ipsum
      security:
      - basic: []
      - token: []
      parameters:
      - $ref: '#/components/parameters/to'
      responses:
        '200':
          $ref: '#/components/responses/success'

components:
  schemas:
    stanza:
      type: object
      example:
        body: Hello
        type: chat
        kind: message
        to: alice@example.com
        state: active
      oneOf:
        - $ref: '#/components/schemas/message'
        - $ref: '#/components/schemas/presence'
        - $ref: '#/components/schemas/iq'

    message:
      type: object
      xml:
        name: message
      properties:
        kind:
          description: Which kind of stanza
          type: string
          enum:
          - message
        type:
          type: string
          enum:
          - chat
          - error
          - groupchat
          - headline
          - normal
          xml:
            attribute: true

        to:
          $ref: '#/components/schemas/to'
        from:
          $ref: '#/components/schemas/from'
        id:
          $ref: '#/components/schemas/id'
        lang:
          $ref: '#/components/schemas/lang'

        body:
          $ref: '#/components/schemas/body'
        subject:
          $ref: '#/components/schemas/subject'
        thread:
          $ref: '#/components/schemas/thread'
        invite:
          $ref: '#/components/schemas/invite'

        state:
          $ref: '#/components/schemas/state'
        nick:
          $ref: '#/components/schemas/nick'
        delay:
          $ref: '#/components/schemas/delay'
        replace:
          $ref: '#/components/schemas/replace'

        html:
          $ref: '#/components/schemas/html'
        oob:
          $ref: '#/components/schemas/oob'
        reactions:
          $ref: '#/components/schemas/reactions'
        occupant_id:
          $ref: '#/components/schemas/occupant_id'
        attach_to:
          $ref: '#/components/schemas/attach_to'
        fallback:
          $ref: '#/components/schemas/fallback'
        stanza_ids:
          $ref: '#/components/schemas/stanza_ids'
        reference:
          $ref: '#/components/schemas/reference'
        reply:
          $ref: '#/components/schemas/reply'
        markable:
          $ref: '#/components/schemas/markable'
        displayed:
          $ref: '#/components/schemas/displayed'
        encryption:
          $ref: '#/components/schemas/encryption'

        archive:
          $ref: '#/components/schemas/archive_result'

        dataform:
          $ref: '#/components/schemas/dataform'

        forwarded:
          $ref: '#/components/schemas/forwarded'

        error:
          $ref: '#/components/schemas/error'

    presence:
      type: object
      properties:
        kind:
          description: Which kind of stanza
          type: string
          enum:
          - presence
        type:
          type: string
          enum:
            - available
            - unavailable
            - subscribe
            - subscribed
            - unsubscribe
            - unsubscribed
            - error
          xml:
            attribute: true
        to:
          $ref: '#/components/schemas/to'
        from:
          $ref: '#/components/schemas/from'
        id:
          $ref: '#/components/schemas/id'
        lang:
          $ref: '#/components/schemas/lang'

        show:
          $ref: '#/components/schemas/show'
        status:
          $ref: '#/components/schemas/status'
        priority:
          $ref: '#/components/schemas/priority'

        caps:
          $ref: '#/components/schemas/caps'
        nick:
          $ref: '#/components/schemas/nick'
        delay:
          $ref: '#/components/schemas/delay'
        vcard_update:
          $ref: '#/components/schemas/vcard_update'
        idle_since:
          $ref: '#/components/schemas/idle_since'

        muc:
          $ref: '#/components/schemas/muc'

        error:
          $ref: '#/components/schemas/error'

    iq:
      type: object
      properties:
        kind:
          description: Which kind of stanza
          type: string
          enum:
          - iq
        type:
          type: string
          enum:
          - get
          - set
          - result
          - error
          xml:
            attribute: true
        to:
          $ref: '#/components/schemas/to'
        from:
          $ref: '#/components/schemas/from'
        id:
          $ref: '#/components/schemas/id'
        lang:
          $ref: '#/components/schemas/lang'

        ping:
          $ref: '#/components/schemas/ping'
        version:
          $ref: '#/components/schemas/version'
        lastactivity:
          $ref: '#/components/schemas/lastactivity'
        disco:
          $ref: '#/components/schemas/disco'
        items:
          $ref: '#/components/schemas/items'
        command:
          $ref: '#/components/schemas/command'

        stats:
          $ref: '#/components/schemas/stats'
        payload:
          $ref: '#/components/schemas/payload'
        gateway:
          $ref: '#/components/schemas/gateway'
        register:
          $ref: '#/components/schemas/register'
        extdisco:
          $ref: '#/components/schemas/extdisco'
        upload_request:
          $ref: '#/components/schemas/upload_request'
        upload_slot:
          $ref: '#/components/schemas/upload_slot'

        error:
          $ref: '#/components/schemas/error'

    iq_pong:
      description: Test reachability of some XMPP address
      type: object
      xml:
        name: iq
      properties:
        type:
          type: string
          enum:
          - result
          xml:
            attribute: true

    iq_result_version:
      description: Version query response
      type: object
      xml:
        name: iq
      properties:
        type:
          type: string
          enum:
          - result
          xml:
            attribute: true
        version:
          $ref: '#/components/schemas/version'

    kind:
      description: Which kind of stanza
      type: string
      enum:
      - message
      - presence
      - iq

    type:
      description: Stanza type
      type: string
      enum:
      - chat
      - normal
      - headline
      - groupchat
      - get
      - set
      - result
      - available
      - unavailable
      - subscribe
      - subscribed
      - unsubscribe
      - unsubscribed
      xml:
        attribute: true

    to:
      description: recipient
      example: alice@example.com
      type: string
      xml:
        attribute: true

    from:
      description: the sender
      example: bob@localhost.example
      type: string
      xml:
        attribute: true

    id:
      description: Reasonably unique id. mod_rest generates one if left out.
      type: string
      xml:
        attribute: true

    lang:
      description: Language code
      example: en
      xml:
        prefix: xml
        attribute: true
      type: string

    body:
      description: Human-readable chat message
      example: Hello, World!
      type: string

    subject:
      description: Subject of message or group chat
      example: Talking about stuff
      type: string

    thread:
      description: Message thread identifier
      properties:
        parent:
          type: string
          xml:
            attribute: true
        id:
          type: string
          xml:
            text: true

    show:
      description: indicator of availability, ie away or not
      type: string
      enum:
      - away
      - chat
      - dnd
      - xa

    status:
      description: Textual status message.
      type: string

    priority:
      description: Presence priority
      type: integer
      maximum: 127
      minimum: -128

    state:
      description: Chat state notifications, e.g. "is typing..."
      type: string
      xml:
        namespace: http://jabber.org/protocol/chatstates
        x_name_is_value: true
      enum:
      - active
      - inactive
      - gone
      - composing
      - paused
      example: composing

    nick:
      type: string
      description: Nickname of the sender
      xml:
        name: nick
        namespace: http://jabber.org/protocol/nick

    delay:
      type: string
      format: date-time
      description: Timestamp of when a stanza was delayed, in ISO 8601 / XEP-0082
        format.
      xml:
        name: delay
        namespace: urn:xmpp:delay
        x_single_attribute: stamp

    replace:
      type: string
      description: ID of message being replaced (e.g. for corrections)
      xml:
        name: replace
        namespace: urn:xmpp:message-correct:0
        x_single_attribute: id

    muc:
      description: Multi-User-Chat related
      type: object
      xml:
        name: x
        namespace: http://jabber.org/protocol/muc
      properties:
        history:
          type: object
          properties:
            maxchars:
              type: integer
              minimum: 0
              xml:
                attribute: true
            maxstanzas:
              type: integer
              minimum: 0
              xml:
                attribute: true
            seconds:
              type: integer
              minimum: 0
              xml:
                attribute: true
            since:
              type: string
              format: date-time
              xml:
                attribute: true


    invite:
      description: Invite to a group chat
      title: "XEP-0249: Direct MUC Invitations"
      type: object
      required:
      - jid
      xml:
        name: x
        namespace: jabber:x:conference
      properties:
        jid:
          type: string
          description: Address of the group chat
          format: xmpp-jid
          xml:
            attribute: true
        reason:
          type: string
          description: Optional message by the inviter
          xml:
            attribute: true
        password:
          type: string
          description: Password for the group chat, if required
          xml:
            attribute: true
        thread:
          type: string
          xml:
            attribute: true
        continue:
          type: boolean
          description: Whether the group chat continues a one-to-one chat
          xml:
            attribute: true

    html:
      description: HTML version of 'body'
      example: <body><p>Hello!</p></body>
      type: string

    ping:
      description: A ping.
      type: boolean
      enum:
      - true
      xml:
        name: ping
        namespace: urn:xmpp:ping

    version:
      type: object
      description: Software version query
      properties:
        name:
          type: string
          example: My Software
        version:
          type: string
          example: 1.0.0
        os:
          type: string
          example: Linux
      required:
      - name
      - version
      xml:
        name: query
        namespace: jabber:iq:version

    disco:
      description: Discover supported features
      oneOf:
      - description: A full response
        type: object
        properties:
          features:
            description: List of URIs indicating supported features
            type: array
            items:
              type: string
          identities:
            description: List of abstract identities or types that describe the
              entity
            type: array
            example:
            - name: Prosody
              type: im
              category: server
            items:
              type: object
              properties:
                name:
                  type: string
                type:
                  type: string
                category:
                  type: string
          node:
            type: string
          extensions:
            type: object
      - description: A query with a node, or an empty response with a node
        type: string
      - description: Either a query, or an empty response
        type: boolean

    items:
      description: List of references to other entities
      oneOf:
      - description: List of items referenced
        type: array
        items:
          properties:
            jid:
              type: string
              description: Address of item
            node:
              type: string
            name:
              type: string
              description: Descriptive name
          required:
          - jid
          type: object
      - type: string
        description: A query with a node, or an empty reply list with a node
      - description: An items query or empty list
        type: boolean
        enum:
        - true

    command:
      description: Ad-hoc commands.
      oneOf:
      - type: object
        properties:
          data:
            $ref: '#/components/schemas/formdata'
          action:
            type: string
          note:
            type: object
            properties:
              text:
                type: string
              type:
                type: string
                enum:
                - info
                - warn
                - error
          form:
            $ref: '#/components/schemas/dataform'
          sessionid:
            type: string
          status:
            type: string
          node:
            type: string
          actions:
            type: object
            properties:
              complete:
                type: boolean
              prev:
                type: boolean
              next:
                type: boolean
              execute:
                type: string
      - type: string
        description: Call a command by 'node' id, without arguments

    oob:
      type: object
      description: Reference a media file
      xml:
        name: x
        namespace: jabber:x:oob
      properties:
        url:
          type: string
          description: URL of the attached media file
          example: https://media.example.net/thisfile.jpg
          format: uri
        desc:
          description: Optional description
          type: string

    payload:
      title: 'XEP-0335: JSON Containers'
      description: A piece of arbitrary JSON with a type field attached
      type: object
      xml:
        name: payload
        namespace: urn:xmpp:json-msg:0
      required:
        - datatype
        - data
      properties:
        data:
          example: '{"some":"json"}'
          type: object
        datatype:
          example: urn:example:my-json#payload
          type: string

    rsm:
      title: 'XEP-0059: Result Set Management'
      xml:
        name: set
        namespace: http://jabber.org/protocol/rsm
      type: object
      properties:
        last:
          type: string
        max:
          type: integer
        index:
          type: integer
        count:
          type: integer
        before:
          type: string
        after:
          type: string
        first:
          type: string

    archive_query:
      title: 'XEP-0313: Message Archive Management'
      type: object
      properties:
        queryid:
          xml:
            attribute: true
          type: string
        page:
          $ref: '#/components/schemas/rsm'
        form:
          $ref: '#/components/schemas/dataform'
      xml:
        name: query
        namespace: urn:xmpp:mam:2

    archive_result:
      title: 'XEP-0313: Message Archive Management'
      xml:
        namespace: urn:xmpp:mam:2
        name: result
      type: object
      properties:
        queryid:
          type: string
          xml:
            attribute: true
        forward:
          $ref: '#/components/schemas/forwarded'

    forwarded:
      title: 'XEP-0297: Stanza Forwarding'
      xml:
        name: forwarded
        namespace: urn:xmpp:forward:0
      type: object
      properties:
        message:
          $ref: '#/components/schemas/message'
        delay:
          $ref: '#/components/schemas/delay'

    dataform:
      description: Data form
      type: object
      properties:
        title:
          description: Title of the form
          example: TPS Report
          type: string
        fields:
          type: array
          items:
            description: Form field
            type: object
            properties:
              value:
                description: Field value
                oneOf:
                - type: string
                - type: array
                  items:
                    type: string
              type:
                description: Type of form field
                type: string
              label:
                description: Descriptive label for the field
                type: string
              desc:
                description: Longer description, i.e. that would go in a tooltip
                type: string
              required:
                description: Whether the field must be included in the form
                type: boolean
              var:
                description: Internal name of the field
                type: string
        type:
          type: string
          enum:
          - form
          - submit
          - cancel
          - result
        instructions:
          type: string

    formdata:
      description: Simplified data form carrying only values
      type: object
      additionalProperties:
        oneOf:
        - type: string
        - type: array
          items:
            type: string

    stats:
      description: Statistics
      type: array
      xml:
        name: query
        namespace: http://jabber.org/protocol/stats
        wrapped: true
      items:
        type: object
        properties:
          name:
            type: string
            xml:
              attribute: true
          unit:
            type: string
            xml:
              attribute: true
          value:
            type: string
            xml:
              attribute: true

    lastactivity:
      type: object
      xml:
        name: query
        namespace: jabber:iq:last
      properties:
        seconds:
          type: integer
          minimum: 0
          xml:
            attribute: true
        status:
          type: string
          xml:
            text: true

    caps:
      type: object
      xml:
        name: c
        namespace: http://jabber.org/protocol/caps
      properties:
        ver:
          type: string
          xml:
            attribute: true
        hash:
          type: string
          xml:
            attribute: true
        node:
          type: string
          xml:
            attribute: true
        ext:
          type: string
          xml:
            attribute: true

    vcard_update:
      type: object
      xml:
        name: x
        namespace: vcard-temp:x:update
      properties:
        photo:
          type: string
          example: adc83b19e793491b1c6ea0fd8b46cd9f32e592fc

    reactions:
      type: object
      xml:
        namespace: urn:xmpp:reactions:0
      properties:
        id:
          type: string
          xml:
            attribute: true
        reactions:
          type: array
          items:
            xml:
              name: reaction
            type: string
          xml:
            wrapped: false
            name: reactions

    occupant_id:
      type: string
      xml:
        namespace: urn:xmpp:occupant-id:0
        x_single_attribute: id
        name: occupant-id

    attach_to:
      type: string
      xml:
        namespace: urn:xmpp:message-attaching:1
        x_single_attribute: id
        name: attach-to

    fallback:
      type: boolean
      xml:
        namespace: urn:xmpp:fallback:0
        x_name_is_value: true
        name: fallback

    stanza_ids:
      type: array
      items:
        type: object
        required:
        - id
        - by
        xml:
          namespace: urn:xmpp:sid:0
          name: stanza-id
        properties:
          id:
            xml:
              attribute: true
            type: string
          by:
            xml:
              attribute: true
            format: xmpp-jid
            type: string

    reference:
      type: object
      xml:
        namespace: urn:xmpp:reference:0
      properties:
        end:
          minimum: 0
          xml:
            attribute: true
          type: integer
        uri:
          xml:
            attribute: true
          format: uri
          type: string
        begin:
          minimum: 0
          xml:
            attribute: true
          type: integer
        type:
          xml:
            attribute: true
          type: string
      required:
      - type
      - uri

    reply:
      title: 'XEP-0461: Message Replies'
      description: Reference a message being replied to
      type: object
      xml:
        name: reply
        namespace: urn:xmpp:reply:0
      properties:
        to:
          type: string
          xml:
            attribute: true
        id:
          type: string
          xml:
            attribute: true

    markable:
      type: boolean
      xml:
        namespace: urn:xmpp:chat-markers:0
        x_name_is_value: true

    displayed:
      type: string
      description: Message ID of a message that has been displayed
      xml:
        namespace: urn:xmpp:chat-markers:0
        x_single_attribute: id

    idle_since:
      type: string
      xml:
        namespace: urn:xmpp:idle:1
        x_single_attribute: since
        name: idle
      format: date-time

    gateway:
      type: object
      xml:
        namespace: jabber:iq:gateway
        name: query
      properties:
        desc:
          type: string
        prompt:
          type: string
        jid:
          type: string

    extdisco:
      type: object
      xml:
        namespace: urn:xmpp:extdisco:2
        name: services
      properties:
        type:
          xml:
            attribute: true
          type: string
        services:
          items:
            type: object
            xml:
              name: service
            required:
            - type
            - host
            properties:
              transport:
                xml:
                  attribute: true
                type: string
              type:
                xml:
                  attribute: true
                type: string
              port:
                xml:
                  attribute: true
                type: integer
              host:
                xml:
                  attribute: true
                type: string
              expires:
                xml:
                  attribute: true
                format: datetime
                type: string
              username:
                xml:
                  attribute: true
                type: string
              password:
                xml:
                  attribute: true
                type: string
              restricted:
                xml:
                  attribute: true
                type: boolean
              name:
                xml:
                  attribute: true
                type: string
          type: array

    register:
      type: object
      description: Register with a service
      xml:
        namespace: jabber:iq:register
        name: query
      properties:
        nick:
          type: string
        misc:
          type: string
        password:
          type: string
        date:
          type: string
        address:
          type: string
        key:
          type: string
        text:
          type: string
        url:
          type: string
        zip:
          type: string
        phone:
          type: string
        last:
          type: string
        email:
          type: string
        remove:
          xml:
            x_name_is_value: true
          type: boolean
        city:
          type: string
        registered:
          xml:
            x_name_is_value: true
          type: boolean
        first:
          type: string
        state:
          type: string
        instructions:
          type: string
        username:
          type: string
        name:
          type: string
      required:
      - username
      - password

    upload_slot:
      type: object
      xml:
        name: slot
        namespace: urn:xmpp:http:upload:0
      properties:
        put:
          type: object
          properties:
            url:
              type: string
              format: uri
              xml:
                attribute: true
            headers:
              type: array
              items:
                type: object
                required:
                - name
                - value
                xml:
                  name: header
                properties:
                  name:
                    type: string
                    enum:
                    - Authorization
                    - Cookie
                    - Expires
                    xml:
                      attribute: true
                  value:
                    type: string
                    xml:
                      text: true
        get:
          type: object
          properties:
            url:
              type: string
              format: uri
              xml:
                attribute: true
    upload_request:
      type: object
      required:
      - filename
      - size
      xml:
        name: request
        namespace: urn:xmpp:http:upload:0
      properties:
        filename:
          type: string
          xml:
            attribute: true
        content-type:
          xml:
            attribute: true
            name: content-type
        size:
          type: integer
          xml:
            attribute: true

    encryption:
      title: 'XEP-0380: Explicit Message Encryption'
      type: string
      xml:
        x_single_attribute: namespace
        name: encryption
        namespace: urn:xmpp:eme:0

    error:
      description: Description of something gone wrong. See the Stanza Errors section in RFC 6120.
      type: object
      properties:
        type:
          description: General category of error
          type: string
          enum:
          - auth
          - cancel
          - continue
          - modify
          - wait
        condition:
          description: Specific error condition.
          type: string
          # enum: [ full list available in RFC 6120 ]
        code:
          description: Legacy numeric error code. Similar to HTTP status codes.
          type: integer
        text:
          description: Description of error intended for human eyes.
          type: string

  securitySchemes:
    token:
      description: Tokens from mod_http_oauth2.
      scheme: Bearer
      type: http
    basic:
      description: Use JID as username.
      scheme: Basic
      type: http

  requestBodies:
    common:
      required: true
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/stanza'
        application/xmpp+xml:
          schema:
            description: Single XMPP stanza in XML format.
        application/x-www-form-urlencoded:
          schema:
            description: A subset of the JSON schema, only top level string fields.

  responses:
    success:
      description: The stanza was sent and returned a response.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/stanza'
        application/xmpp+xml:
          schema:
            description: Single XMPP stanza in XML format.
            example: <message><body>Hello</body></message>
        application/x-www-form-urlencoded:
          schema:
            description: A subset of the JSON schema, only top level string fields.
            example: body=Hello
        text/plain:
          schema:
            description: Plain text response used as message body.
            example: Hello
            type: string
    sent:
      description: The stanza was sent without problem, and without response,
        so an empty reply.

  parameters:
    to:
      name: to
      in: path
      required: true
      schema:
        $ref: '#/components/schemas/to'
    kind:
      name: kind
      in: path
      required: true
      schema:
        $ref: '#/components/schemas/kind'
    type:
      name: type
      in: path
      required: true
      schema:
        $ref: '#/components/schemas/type'

...