Metadata API Reference: Actions¶
Table of contents
Introduction¶
actions are user defined mutations with custom business logic.
Supported from
The metadata API is supported for versions v2.0.0 and above and replaces the older
schema/metadata API.
create_action¶
create_action is used to define an action. There shouldn’t be an existing action with the same name.
Create a synchronous action with name create_user:
POST /v1/metadata HTTP/1.1
Content-Type: application/json
X-Hasura-Role: admin
{
   "type":"create_action",
   "args":{
      "name":"create_user",
      "definition":{
         "kind":"synchronous",
         "arguments":[
            {
               "name":"username",
               "type":"String!"
            },
            {
               "name":"email",
               "type":"String!"
            }
         ],
         "output_type":"User",
         "handler":"https://action.my_app.com/create-user",
         "timeout":60
      },
      "comment": "Custom action to create user"
   }
}
Args syntax¶
| Key | Required | Schema | Description | 
|---|---|---|---|
| name | true | ActionName | Name of the action | 
| definition | true | ActionDefinition | Definition of the action | 
| comment | false | text | comment | 
Note
The GraphQL Types used in creating an action must be defined before via Custom Types
drop_action¶
drop_action is used to remove an action. Permissions defined on the actions are also dropped automatically.
Drop an action create_user:
POST /v1/metadata HTTP/1.1
Content-Type: application/json
X-Hasura-Role: admin
{
   "type":"drop_action",
   "args":{
      "name":"create_user",
      "clear_data": true
   }
}
Args syntax¶
| Key | Required | Schema | Description | 
|---|---|---|---|
| name | true | ActionName | Name of the action | 
| clear_data | false | boolean | If set to trueand action kind isasynchronous, related data is deleted from catalog. (default:true) | 
update_action¶
update_action is used to update the definition of the action. Definition thus provided is
replaced with existing one.
Update an action create_user by making it’s kind to asynchronous:
POST /v1/metadata HTTP/1.1
Content-Type: application/json
X-Hasura-Role: admin
{
   "type":"update_action",
   "args":{
      "name":"create_user",
      "definition":{
         "kind":"asynchronous",
         "arguments":[
            {
               "name":"username",
               "type":"String!"
            },
            {
               "name":"email",
               "type":"String!"
            }
         ],
         "output_type":"User",
         "handler":"https://action.my_app.com/create-user"
      }
   }
}
Args syntax¶
| Key | Required | Schema | Description | 
|---|---|---|---|
| name | true | ActionName | Name of the action | 
| definition | true | ActionDefinition | Definition of the action to be replaced | 
create_action_permission¶
create_action_permission is used to define a permission to make action visible for a role.
POST /v1/metadata HTTP/1.1
Content-Type: application/json
X-Hasura-Role: admin
{
  "type": "create_action_permission",
  "args": {
    "action": "create_user",
    "role": "user"
  }
}
Args syntax¶
| Key | Required | Schema | Description | 
|---|---|---|---|
| action | true | ActionName | Name of the action | 
| role | true | RoleName | Name of the role | 
| comment | false | text | comment | 
drop_action_permission¶
drop_action_permission is used to drop a permission defined on an action.
POST /v1/metadata HTTP/1.1
Content-Type: application/json
X-Hasura-Role: admin
{
  "type": "drop_action_permission",
  "args": {
    "action": "create_user",
    "role": "user"
  }
}
Args syntax¶
| Key | Required | Schema | Description | 
|---|---|---|---|
| name | true | ActionName | Name of the action | 
| role | true | RoleName | Name of the role | 
