> ## Documentation Index
> Fetch the complete documentation index at: https://proxy-docs.permify.co/llms.txt
> Use this file to discover all available pages before exploring further.

# Watch API

The Permify Watch API acts as a real-time broadcaster that shows changes in the relation tuples.

The Watch API exclusively supports gRPC and works with PostgreSQL, given the track\_commit\_timestamp option is enabled. Please note, it doesn't support in-memory databases or HTTP communication.

## Requirements

* PostgreSQL database set up with track\_commit\_timestamp option enabled

## Enabling track\_commit\_timestamp on PostgreSQL

To ensure data consistency and synchronization between your application and Permify, enable track\_commit\_timestamp on
your PostgreSQL server. This can be done by executing the following options in your PostgreSQL:

### Option 1: SQL Command

1. Open your PostgreSQL command line interface.

2. Execute the following command:

   ```sql theme={null}
   ALTER SYSTEM SET track_commit_timestamp = ON;
   ```

3. Reload the configuration with the following command:

   ```sql theme={null}
   SELECT pg_reload_conf();
   ```

### Option 2: Editing postgresql.conf

1. Find and open the postgresql.conf file in a text editor. Its location depends on your PostgreSQL installation. Common
   locations are:
   * Debian-based systems: /etc/postgresql/\[version]/main/postgresql.conf
   * Red Hat-based systems: /var/lib/pgsql/data/postgresql.conf

2. Add or modify the following line in the postgresql.conf file:
   ```
   track_commit_timestamp = on
   ```

3. Save and close the postgresql.conf file.

4. Reload the PostgreSQL configuration for the changes to take effect. This can be done via the PostgreSQL console:

   ```sql theme={null}
   SELECT pg_reload_conf();
   ```

   Or if you have command line access, use:

   ```bash theme={null}
   sudo service postgresql reload
   ```

Please ensure you have the necessary permissions to execute these commands or modify the postgresql.conf file. Also, remember that changes in the postgresql.conf file will persist across restarts, while the SQL method may need to be reapplied depending on your PostgreSQL version and setup.

<Info>
  Important Configuration Requirement: To use the Watch API, it must be enabled in your configuration file. Add or modify the following lines:

  ```yaml theme={null}
  service:
    watch:
      enabled: true
  ```
</Info>

For performance guidance, scaling strategies, and reconnection best practices, see [Watch — Operations](/operations/watch).


## OpenAPI

````yaml post /v1/tenants/{tenant_id}/watch
openapi: 3.0.0
info:
  title: Permify API
  description: >-
    Permify is an open source authorization service for creating fine-grained
    and scalable authorization systems.
  version: v1.6.10
  contact:
    name: API Support
    url: https://github.com/Permify/permify/issues
    email: hello@permify.co
  license:
    name: AGPL-3.0 license
    url: https://github.com/Permify/permify/blob/master/LICENSE
servers: []
security: []
tags:
  - name: Permission
  - name: Watch
  - name: Schema
  - name: Data
  - name: Bundle
  - name: Tenancy
paths:
  /v1/tenants/{tenant_id}/watch:
    post:
      tags:
        - Watch
      summary: watch changes
      operationId: watch.watch
      parameters:
        - name: tenant_id
          description: >-
            Identifier of the tenant, if you are not using multi-tenancy (have
            only one tenant) use pre-inserted tenant <code>t1</code> for this
            field. Required, and must match the pattern \“[a-zA-Z0-9-,]+\“, max
            64 bytes.
          in: path
          required: true
          schema:
            type: string
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/WatchBody'
        required: true
      responses:
        '200':
          description: A successful response.(streaming responses)
          content:
            application/json:
              schema:
                type: object
                properties:
                  result:
                    $ref: '#/components/schemas/WatchResponse'
                  error:
                    $ref: '#/components/schemas/Status'
                title: Stream result of WatchResponse
        default:
          description: An unexpected error response.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Status'
      x-codeSamples:
        - label: go
          lang: go
          source: >
            cr, err := client.Watch.Watch(context.Background(),
            &v1.WatchRequest{
                TenantId:  "t1",
                SnapToken: "",
            })

            // handle stream response

            for {
                res, err := cr.Recv()

                if err == io.EOF {
                    break
                }

                // res.Changes
            }
        - label: node
          lang: javascript
          source: >
            const permify = require("@permify/permify-node");

            const {WatchResponse} =
            require("@permify/permify-node/dist/src/grpc/generated/base/v1/service");


            function main() {
                const client = new permify.grpc.newClient({
                    endpoint: "localhost:3478",
                });

                let res = client.watch.watch({
                    tenantId: "t1",
                    snapToken: ""
                });

                handle(res);
            }


            async function handle(res: AsyncIterable<WatchResponse>) {
                for await (const response of res) {
                    // response.changes
                }
            }
components:
  schemas:
    WatchBody:
      type: object
      properties:
        snap_token:
          type: string
          description: >-
            The snap token to avoid stale cache, see more details on [Snap
            Tokens](../../operations/snap-tokens).
      description: |-
        WatchRequest is the request message for the Watch RPC. It contains the
        details needed to establish a watch stream.
    WatchResponse:
      type: object
      properties:
        changes:
          $ref: '#/components/schemas/DataChanges'
      description: |-
        WatchResponse is the response message for the Watch RPC. It contains the
        changes in the data that are being watched.
    Status:
      type: object
      properties:
        code:
          type: integer
          format: int32
        message:
          type: string
        details:
          type: array
          items:
            $ref: '#/components/schemas/Any'
    DataChanges:
      type: object
      properties:
        snap_token:
          type: string
          description: The snapshot token.
        data_changes:
          type: array
          items:
            $ref: '#/components/schemas/DataChange'
          description: The list of data changes.
      description: >-
        DataChanges represent changes in data with a snap token and a list of
        data change objects.
    Any:
      type: object
      properties:
        '@type':
          type: string
          description: >-
            A URL/resource name that uniquely identifies the type of the
            serialized

            protocol buffer message. This string must contain at least

            one "/" character. The last segment of the URL's path must represent

            the fully qualified name of the type (as in

            `path/google.protobuf.Duration`). The name should be in a canonical
            form

            (e.g., leading "." is not accepted).


            In practice, teams usually precompile into the binary all types that
            they

            expect it to use in the context of Any. However, for URLs which use
            the

            scheme `http`, `https`, or no scheme, one can optionally set up a
            type

            server that maps type URLs to message definitions as follows:


            * If no scheme is provided, `https` is assumed.

            * An HTTP GET on the URL must yield a [google.protobuf.Type][]
              value in binary format, or produce an error.
            * Applications are allowed to cache lookup results based on the
              URL, or have them precompiled into a binary to avoid any
              lookup. Therefore, binary compatibility needs to be preserved
              on changes to types. (Use versioned type names to manage
              breaking changes.)

            Note: this functionality is not currently available in the official

            protobuf release, and it is not used for type URLs beginning with

            type.googleapis.com. As of May 2023, there are no widely used type
            server

            implementations and no plans to implement one.


            Schemes other than `http`, `https` (or the empty scheme) might be

            used with implementation specific semantics.
      additionalProperties: {}
      description: >-
        `Any` contains an arbitrary serialized protocol buffer message along
        with a

        URL that describes the type of the serialized message.


        Protobuf library provides support to pack/unpack Any values in the form

        of utility functions or additional generated methods of the Any type.


        Example 1: Pack and unpack a message in C++.

            Foo foo = ...;
            Any any;
            any.PackFrom(foo);
            ...
            if (any.UnpackTo(&foo)) {
              ...
            }

        Example 2: Pack and unpack a message in Java.

            Foo foo = ...;
            Any any = Any.pack(foo);
            ...
            if (any.is(Foo.class)) {
              foo = any.unpack(Foo.class);
            }
            // or ...
            if (any.isSameTypeAs(Foo.getDefaultInstance())) {
              foo = any.unpack(Foo.getDefaultInstance());
            }

         Example 3: Pack and unpack a message in Python.

            foo = Foo(...)
            any = Any()
            any.Pack(foo)
            ...
            if any.Is(Foo.DESCRIPTOR):
              any.Unpack(foo)
              ...

         Example 4: Pack and unpack a message in Go

             foo := &pb.Foo{...}
             any, err := anypb.New(foo)
             if err != nil {
               ...
             }
             ...
             foo := &pb.Foo{}
             if err := any.UnmarshalTo(foo); err != nil {
               ...
             }

        The pack methods provided by protobuf library will by default use

        'type.googleapis.com/full.type.name' as the type URL and the unpack

        methods only use the fully qualified type name after the last '/'

        in the type URL, for example "foo.bar.com/x/y.z" will yield type

        name "y.z".


        JSON

        ====

        The JSON representation of an `Any` value uses the regular

        representation of the deserialized, embedded message, with an

        additional field `@type` which contains the type URL. Example:

            package google.profile;
            message Person {
              string first_name = 1;
              string last_name = 2;
            }

            {
              "@type": "type.googleapis.com/google.profile.Person",
              "firstName": <string>,
              "lastName": <string>
            }

        If the embedded message type is well-known and has a custom JSON

        representation, that representation will be embedded adding a field

        `value` which holds the custom JSON in addition to the `@type`

        field. Example (for message [google.protobuf.Duration][]):

            {
              "@type": "type.googleapis.com/google.protobuf.Duration",
              "value": "1.212s"
            }
    DataChange:
      type: object
      properties:
        operation:
          $ref: '#/components/schemas/DataChange.Operation'
        tuple:
          $ref: '#/components/schemas/Tuple'
        attribute:
          $ref: '#/components/schemas/Attribute'
      description: >-
        DataChange represents a single change in data, with an operation type
        and the actual change which could be a tuple or an attribute.
    DataChange.Operation:
      type: string
      enum:
        - OPERATION_UNSPECIFIED
        - OPERATION_CREATE
        - OPERATION_DELETE
      default: OPERATION_UNSPECIFIED
      description: |2-
         - OPERATION_UNSPECIFIED: Default operation, not specified.
         - OPERATION_CREATE: Creation operation.
         - OPERATION_DELETE: Deletion operation.
    Tuple:
      type: object
      properties:
        entity:
          $ref: '#/components/schemas/Entity'
        relation:
          type: string
        subject:
          $ref: '#/components/schemas/Subject'
      description: Tuple is a structure that includes an entity, a relation, and a subject.
    Attribute:
      type: object
      properties:
        entity:
          $ref: '#/components/schemas/Entity'
        attribute:
          type: string
          title: Name of the attribute
        value:
          $ref: '#/components/schemas/Any'
      description: >-
        Attribute represents an attribute of an entity with a specific type and
        value.
    Entity:
      type: object
      properties:
        type:
          type: string
        id:
          type: string
      description: Entity represents an entity with a type and an identifier.
    Subject:
      type: object
      properties:
        type:
          type: string
        id:
          type: string
        relation:
          type: string
      description: >-
        Subject represents an entity subject with a type, an identifier, and a
        relation.

````