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Go API client for airflow

Overview

To facilitate management, Apache Airflow supports a range of REST API endpoints across its objects. This section provides an overview of the API design, methods, and supported use cases.

Most of the endpoints accept JSON as input and return JSON responses. This means that you must usually add the following headers to your request:

Content-type: application/json
Accept: application/json

Resources

The term resource refers to a single type of object in the Airflow metadata. An API is broken up by its endpoint's corresponding resource. The name of a resource is typically plural and expressed in camelCase. Example: dagRuns.

Resource names are used as part of endpoint URLs, as well as in API parameters and responses.

CRUD Operations

The platform supports Create, Read, Update, and Delete operations on most resources. You can review the standards for these operations and their standard parameters below.

Some endpoints have special behavior as exceptions.

Create

To create a resource, you typically submit an HTTP POST request with the resource's required metadata in the request body. The response returns a 201 Created response code upon success with the resource's metadata, including its internal id, in the response body.

Read

The HTTP GET request can be used to read a resource or to list a number of resources.

A resource's id can be submitted in the request parameters to read a specific resource. The response usually returns a 200 OK response code upon success, with the resource's metadata in the response body.

If a GET request does not include a specific resource id, it is treated as a list request. The response usually returns a 200 OK response code upon success, with an object containing a list of resources' metadata in the response body.

When reading resources, some common query parameters are usually available. e.g.:

v1/connections?limit=25&offset=25
Query Parameter Type Description
limit integer Maximum number of objects to fetch. Usually 25 by default
offset integer Offset after which to start returning objects. For use with limit query parameter.

Update

Updating a resource requires the resource id, and is typically done using an HTTP PATCH request, with the fields to modify in the request body. The response usually returns a 200 OK response code upon success, with information about the modified resource in the response body.

Delete

Deleting a resource requires the resource id and is typically executing via an HTTP DELETE request. The response usually returns a 204 No Content response code upon success.

Conventions

  • Resource names are plural and expressed in camelCase.

  • Names are consistent between URL parameter name and field name.

  • Field names are in snake_case.

{
    \"name\": \"string\",
    \"slots\": 0,
    \"occupied_slots\": 0,
    \"used_slots\": 0,
    \"queued_slots\": 0,
    \"open_slots\": 0
}

Update Mask

Update mask is available as a query parameter in patch endpoints. It is used to notify the API which fields you want to update. Using update_mask makes it easier to update objects by helping the server know which fields to update in an object instead of updating all fields. The update request ignores any fields that aren't specified in the field mask, leaving them with their current values.

Example:

  resource = request.get('/resource/my-id').json()
  resource['my_field'] = 'new-value'
  request.patch('/resource/my-id?update_mask=my_field', data=json.dumps(resource))

Versioning and Endpoint Lifecycle

  • API versioning is not synchronized to specific releases of the Apache Airflow.
  • APIs are designed to be backward compatible.
  • Any changes to the API will first go through a deprecation phase.

Trying the API

You can use a third party client, such as curl, HTTPie, Postman or the Insomnia rest client to test the Apache Airflow API.

Note that you will need to pass credentials data.

For e.g., here is how to pause a DAG with curl, when basic authorization is used:

curl -X PATCH 'https://example.com/api/v1/dags/{dag_id}?update_mask=is_paused' \\
-H 'Content-Type: application/json' \\
--user \"username:password\" \\
-d '{
    \"is_paused\": true
}'

Using a graphical tool such as Postman or Insomnia, it is possible to import the API specifications directly:

  1. Download the API specification by clicking the Download button at top of this document
  2. Import the JSON specification in the graphical tool of your choice.
  • In Postman, you can click the import button at the top
  • With Insomnia, you can just drag-and-drop the file on the UI

Note that with Postman, you can also generate code snippets by selecting a request and clicking on the Code button.

Enabling CORS

Cross-origin resource sharing (CORS) is a browser security feature that restricts HTTP requests that are initiated from scripts running in the browser.

For details on enabling/configuring CORS, see Enabling CORS.

Authentication

To be able to meet the requirements of many organizations, Airflow supports many authentication methods, and it is even possible to add your own method.

If you want to check which auth backend is currently set, you can use airflow config get-value api auth_backends command as in the example below.

$ airflow config get-value api auth_backends
airflow.api.auth.backend.basic_auth

The default is to deny all requests.

For details on configuring the authentication, see API Authorization.

Errors

We follow the error response format proposed in RFC 7807 also known as Problem Details for HTTP APIs. As with our normal API responses, your client must be prepared to gracefully handle additional members of the response.

Unauthenticated

This indicates that the request has not been applied because it lacks valid authentication credentials for the target resource. Please check that you have valid credentials.

PermissionDenied

This response means that the server understood the request but refuses to authorize it because it lacks sufficient rights to the resource. It happens when you do not have the necessary permission to execute the action you performed. You need to get the appropriate permissions in other to resolve this error.

BadRequest

This response means that the server cannot or will not process the request due to something that is perceived to be a client error (e.g., malformed request syntax, invalid request message framing, or deceptive request routing). To resolve this, please ensure that your syntax is correct.

NotFound

This client error response indicates that the server cannot find the requested resource.

MethodNotAllowed

Indicates that the request method is known by the server but is not supported by the target resource.

NotAcceptable

The target resource does not have a current representation that would be acceptable to the user agent, according to the proactive negotiation header fields received in the request, and the server is unwilling to supply a default representation.

AlreadyExists

The request could not be completed due to a conflict with the current state of the target resource, e.g. the resource it tries to create already exists.

Unknown

This means that the server encountered an unexpected condition that prevented it from fulfilling the request.

Overview

This API client was generated by the OpenAPI Generator project. By using the OpenAPI-spec from a remote server, you can easily generate an API client.

  • API version: 1.0.0
  • Package version: 2.1.0
  • Build package: org.openapitools.codegen.languages.GoClientCodegen For more information, please visit https://airflow.apache.org

Installation

Install the following dependencies:

go get github.com/stretchr/testify/assert
go get golang.org/x/oauth2
go get golang.org/x/net/context

Put the package under your project folder and add the following in import:

import sw "./airflow"

To use a proxy, set the environment variable HTTP_PROXY:

os.Setenv("HTTP_PROXY", "http://proxy_name:proxy_port")

Configuration of Server URL

Default configuration comes with Servers field that contains server objects as defined in the OpenAPI specification.

Select Server Configuration

For using other server than the one defined on index 0 set context value sw.ContextServerIndex of type int.

ctx := context.WithValue(context.Background(), sw.ContextServerIndex, 1)

Templated Server URL

Templated server URL is formatted using default variables from configuration or from context value sw.ContextServerVariables of type map[string]string.

ctx := context.WithValue(context.Background(), sw.ContextServerVariables, map[string]string{
	"basePath": "v2",
})

Note, enum values are always validated and all unused variables are silently ignored.

URLs Configuration per Operation

Each operation can use different server URL defined using OperationServers map in the Configuration. An operation is uniquely identified by "{classname}Service.{nickname}" string. Similar rules for overriding default operation server index and variables applies by using sw.ContextOperationServerIndices and sw.ContextOperationServerVariables context maps.

ctx := context.WithValue(context.Background(), sw.ContextOperationServerIndices, map[string]int{
	"{classname}Service.{nickname}": 2,
})
ctx = context.WithValue(context.Background(), sw.ContextOperationServerVariables, map[string]map[string]string{
	"{classname}Service.{nickname}": {
		"port": "8443",
	},
})

Documentation for API Endpoints

All URIs are relative to http://localhost/api/v1

Class Method HTTP request Description
ConfigApi GetConfig Get /config Get current configuration
ConnectionApi DeleteConnection Delete /connections/{connection_id} Delete a connection
ConnectionApi GetConnection Get /connections/{connection_id} Get a connection
ConnectionApi GetConnections Get /connections List connections
ConnectionApi PatchConnection Patch /connections/{connection_id} Update a connection
ConnectionApi PostConnection Post /connections Create a connection
ConnectionApi TestConnection Post /connections/test Test a connection
DAGApi DeleteDag Delete /dags/{dag_id} Delete a DAG
DAGApi GetDag Get /dags/{dag_id} Get basic information about a DAG
DAGApi GetDagDetails Get /dags/{dag_id}/details Get a simplified representation of DAG
DAGApi GetDagSource Get /dagSources/{file_token} Get a source code
DAGApi GetDags Get /dags List DAGs
DAGApi GetTask Get /dags/{dag_id}/tasks/{task_id} Get simplified representation of a task
DAGApi GetTasks Get /dags/{dag_id}/tasks Get tasks for DAG
DAGApi PatchDag Patch /dags/{dag_id} Update a DAG
DAGApi PatchDags Patch /dags Update DAGs
DAGApi PostClearTaskInstances Post /dags/{dag_id}/clearTaskInstances Clear a set of task instances
DAGApi PostSetTaskInstancesState Post /dags/{dag_id}/updateTaskInstancesState Set a state of task instances
DAGRunApi DeleteDagRun Delete /dags/{dag_id}/dagRuns/{dag_run_id} Delete a DAG run
DAGRunApi GetDagRun Get /dags/{dag_id}/dagRuns/{dag_run_id} Get a DAG run
DAGRunApi GetDagRuns Get /dags/{dag_id}/dagRuns List DAG runs
DAGRunApi GetDagRunsBatch Post /dags/~/dagRuns/list List DAG runs (batch)
DAGRunApi PostDagRun Post /dags/{dag_id}/dagRuns Trigger a new DAG run
DAGRunApi UpdateDagRunState Patch /dags/{dag_id}/dagRuns/{dag_run_id} Modify a DAG run
EventLogApi GetEventLog Get /eventLogs/{event_log_id} Get a log entry
EventLogApi GetEventLogs Get /eventLogs List log entries
ImportErrorApi GetImportError Get /importErrors/{import_error_id} Get an import error
ImportErrorApi GetImportErrors Get /importErrors List import errors
MonitoringApi GetHealth Get /health Get instance status
MonitoringApi GetVersion Get /version Get version information
PermissionApi GetPermissions Get /permissions List permissions
PluginApi GetPlugins Get /plugins Get a list of loaded plugins
PoolApi DeletePool Delete /pools/{pool_name} Delete a pool
PoolApi GetPool Get /pools/{pool_name} Get a pool
PoolApi GetPools Get /pools List pools
PoolApi PatchPool Patch /pools/{pool_name} Update a pool
PoolApi PostPool Post /pools Create a pool
ProviderApi GetProviders Get /providers List providers
RoleApi DeleteRole Delete /roles/{role_name} Delete a role
RoleApi GetRole Get /roles/{role_name} Get a role
RoleApi GetRoles Get /roles List roles
RoleApi PatchRole Patch /roles/{role_name} Update a role
RoleApi PostRole Post /roles Create a role
TaskInstanceApi GetExtraLinks Get /dags/{dag_id}/dagRuns/{dag_run_id}/taskInstances/{task_id}/links List extra links
TaskInstanceApi GetLog Get /dags/{dag_id}/dagRuns/{dag_run_id}/taskInstances/{task_id}/logs/{task_try_number} Get logs
TaskInstanceApi GetMappedTaskInstance Get /dags/{dag_id}/dagRuns/{dag_run_id}/taskInstances/{task_id}/{map_index} Get a mapped task instance
TaskInstanceApi GetMappedTaskInstances Get /dags/{dag_id}/dagRuns/{dag_run_id}/taskInstances/{task_id}/listMapped List mapped task instances
TaskInstanceApi GetTaskInstance Get /dags/{dag_id}/dagRuns/{dag_run_id}/taskInstances/{task_id} Get a task instance
TaskInstanceApi GetTaskInstances Get /dags/{dag_id}/dagRuns/{dag_run_id}/taskInstances List task instances
TaskInstanceApi GetTaskInstancesBatch Post /dags//dagRuns//taskInstances/list List task instances (batch)
UserApi DeleteUser Delete /users/{username} Delete a user
UserApi GetUser Get /users/{username} Get a user
UserApi GetUsers Get /users List users
UserApi PatchUser Patch /users/{username} Update a user
UserApi PostUser Post /users Create a user
VariableApi DeleteVariable Delete /variables/{variable_key} Delete a variable
VariableApi GetVariable Get /variables/{variable_key} Get a variable
VariableApi GetVariables Get /variables List variables
VariableApi PatchVariable Patch /variables/{variable_key} Update a variable
VariableApi PostVariables Post /variables Create a variable
XComApi GetXcomEntries Get /dags/{dag_id}/dagRuns/{dag_run_id}/taskInstances/{task_id}/xcomEntries List XCom entries
XComApi GetXcomEntry Get /dags/{dag_id}/dagRuns/{dag_run_id}/taskInstances/{task_id}/xcomEntries/{xcom_key} Get an XCom entry

Documentation For Models

Documentation For Authorization

Basic

  • Type: HTTP basic authentication

Example

auth := context.WithValue(context.Background(), sw.ContextBasicAuth, sw.BasicAuth{
    UserName: "username",
    Password: "password",
})
r, err := client.Service.Operation(auth, args)

Kerberos

Documentation for Utility Methods

Due to the fact that model structure members are all pointers, this package contains a number of utility functions to easily obtain pointers to values of basic types. Each of these functions takes a value of the given basic type and returns a pointer to it:

  • PtrBool
  • PtrInt
  • PtrInt32
  • PtrInt64
  • PtrFloat
  • PtrFloat32
  • PtrFloat64
  • PtrString
  • PtrTime

Author

[email protected]