path: root/doc/api/README.md

---
stage: none
group: unassigned
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
---

# API Docs

Automate GitLab by using a simple and powerful API.

The main GitLab API is a [REST](http://spec.openapis.org/oas/v3.0.3)
API. Because of this, the documentation in this section assumes that you're
familiar with REST concepts.

There's also a partial [OpenAPI definition](https://gitlab.com/gitlab-org/gitlab/blob/master/doc/api/openapi/openapi.yaml),
which allows you to test the API directly from the GitLab user interface.
Contributions are welcome.

## Available API resources

For a list of the available resources and their endpoints, see
[API resources](api_resources.md).

## SCIM **(SILVER ONLY)**

GitLab provides an [SCIM API](scim.md) that both implements
[the RFC7644 protocol](https://tools.ietf.org/html/rfc7644) and provides the
`/Users` endpoint. The base URL is `/api/scim/v2/groups/:group_path/Users/`.

## Road to GraphQL

[GraphQL](graphql/index.md) is available in GitLab, which allows for the
deprecation of controller-specific endpoints.

GraphQL has several benefits, including:

- We avoid having to maintain two different APIs.
- Callers of the API can request only what they need.
- It's versioned by default.

GraphQL co-exists with the current v4 REST API. If we have a v5 API, this should
be a compatibility layer on top of GraphQL.

Although there were some patenting and licensing concerns with GraphQL, these
have been resolved to our satisfaction by the relicensing of the reference
implementations under MIT, and the use of the OWF license for the GraphQL
specification.

## Compatibility guidelines

The HTTP API is versioned using a single number, (currently _4_). This number
symbolizes the major version number, as described by [SemVer](https://semver.org/).
Because of this, backwards-incompatible changes require this version number to
change. However, the minor version isn't explicit, allowing for a stable API
endpoint. This also means that new features can be added to the API in the same
version number.

New features and bug fixes are released in tandem with a new GitLab, and apart
from incidental patch and security releases, are released on the 22nd of each
month. Backward incompatible changes (for example, endpoints removal and
parameters removal), and removal of entire API versions are done in tandem with
a major point release of GitLab itself. All deprecations and changes between two
versions should be listed in the documentation. For the changes between v3 and
v4, see the [v3 to v4 documentation](v3_to_v4.md).

### Current status

Only API version v4 is available. Version v3 was removed in
[GitLab 11.0](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/36819).

## Basic usage

API requests should be prefixed with both `api` and the API version. The API
version is defined in [`lib/api.rb`](https://gitlab.com/gitlab-org/gitlab/tree/master/lib/api/api.rb).
For example, the root of the v4 API is at `/api/v4`. The following sections illustrate different uses:

### Valid API request

If you have a GitLab instance at `gitlab.example.com`:

```shell
curl "https://gitlab.example.com/api/v4/projects"
```

The API uses JSON to serialize data. You don't need to specify `.json` at the
end of an API URL.

### API request to expose HTTP response headers

If you want to expose HTTP response headers, use the `--include` option:

```shell
curl --include "https://gitlab.example.com/api/v4/projects"
HTTP/2 200
...
```

This can help you investigate an unexpected response.

### API request that includes the exit code

If you want to expose the HTTP exit code, include the `--fail` option:

```shell script
curl --fail "https://gitlab.example.com/api/v4/does-not-exist"
curl: (22) The requested URL returned error: 404
```

The HTTP exit code can help you diagnose the success or failure of your REST call.

## Authentication

Most API requests require authentication, or only return public data when
authentication isn't provided. For cases where it isn't required, this is
mentioned in the documentation for each individual endpoint (for example, the
[`/projects/:id` endpoint](projects.md#get-single-project)).

There are several methods you can use to authenticate with the GitLab API:

- [OAuth2 tokens](#oauth2-tokens)
- [Personal access tokens](../user/profile/personal_access_tokens.md)
- [Project access tokens](../user/project/settings/project_access_tokens.md)
- [Session cookie](#session-cookie)
- [GitLab CI/CD job token](#gitlab-ci-job-token) **(Specific endpoints only)**

NOTE:
Project access tokens are supported for self-managed instances on Core and
higher. They're also supported on GitLab.com Bronze and higher.

For administrators who want to authenticate with the API as a specific user, or who want
to build applications or scripts that do so, the following options are available:

- [Impersonation tokens](#impersonation-tokens)
- [Sudo](#sudo)

If authentication information is invalid or omitted, GitLab returns an error
message with a status code of `401`:

```json
{
  "message": "401 Unauthorized"
}
```

### OAuth2 tokens

You can use an [OAuth2 token](oauth2.md) to authenticate with the API by passing
it in either the `access_token` parameter or the `Authorization` header.

Example of using the OAuth2 token in a parameter:

```shell
curl "https://gitlab.example.com/api/v4/projects?access_token=OAUTH-TOKEN"
```

Example of using the OAuth2 token in a header:

```shell
curl --header "Authorization: Bearer OAUTH-TOKEN" "https://gitlab.example.com/api/v4/projects"
```

Read more about [GitLab as an OAuth2 provider](oauth2.md).

### Personal/project access tokens

You can use access tokens to authenticate with the API by passing it in either
the `private_token` parameter or the `PRIVATE-TOKEN` header.

Example of using the personal or project access token in a parameter:

```shell
curl "https://gitlab.example.com/api/v4/projects?private_token=<your_access_token>"
```

Example of using the personal or project access token in a header:

```shell
curl --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects"
```

You can also use personal or project access tokens with OAuth-compliant headers:

```shell
curl --header "Authorization: Bearer <your_access_token>" "https://gitlab.example.com/api/v4/projects"
```

### Session cookie

Signing in to the main GitLab application sets a `_gitlab_session` cookie. The
API uses this cookie for authentication if it's present. Using the API to
generate a new session cookie isn't supported.

The primary user of this authentication method is the web frontend of GitLab
itself, which can, for example, use the API as the authenticated user to get a
list of their projects without needing to explicitly pass an access token.

### GitLab CI job token

With a few API endpoints you can use a [GitLab CI/CD job token](../user/project/new_ci_build_permissions_model.md#job-token)
to authenticate with the API:

- Packages:
  - [Composer Repository](../user/packages/composer_repository/index.md)
  - [Conan Repository](../user/packages/conan_repository/index.md)
  - [Container Registry](../user/packages/container_registry/index.md)
    (`$CI_REGISTRY_PASSWORD` is `$CI_JOB_TOKEN`)
  - [Go Proxy](../user/packages/go_proxy/index.md)
  - [Maven Repository](../user/packages/maven_repository/index.md#authenticate-with-a-ci-job-token-in-maven)
  - [NPM Repository](../user/packages/npm_registry/index.md#authenticate-with-a-ci-job-token)
  - [Nuget Repository](../user/packages/nuget_repository/index.md)
  - [PyPI Repository](../user/packages/pypi_repository/index.md#authenticate-with-a-ci-job-token)
  - [Generic packages](../user/packages/generic_packages/index.md#publish-a-generic-package-by-using-cicd)
- [Get job artifacts](job_artifacts.md#get-job-artifacts)
- [Pipeline triggers](pipeline_triggers.md) (using the `token=` parameter)
- [Release creation](releases/index.md#create-a-release)
- [Terraform plan](../user/infrastructure/index.md)

The token is valid as long as the job is running.

### Impersonation tokens

Impersonation tokens are a type of [personal access token](../user/profile/personal_access_tokens.md)
that can be created only by an administrator for a specific user. They can be
useful if you want to build applications or scripts that authenticate with the
API as a specific user.

They're an alternative to directly using the user's password (or one of their
personal access tokens), and to using the [Sudo](#sudo) feature, as the user's
(or administrator's in the case of Sudo) password or token may not be known, or may
change over time.

For more information, see the [users API](users.md#create-an-impersonation-token)
documentation.

Impersonation tokens are used exactly like regular personal access tokens, and
can be passed in either the `private_token` parameter or the `PRIVATE-TOKEN`
header.

#### Disable impersonation

> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/40385) in GitLab 11.6.

By default, impersonation is enabled. To disable impersonation:

**For Omnibus installations**

1. Edit the `/etc/gitlab/gitlab.rb` file:

   ```ruby
   gitlab_rails['impersonation_enabled'] = false
   ```

1. Save the file, and then [reconfigure](../administration/restart_gitlab.md#omnibus-gitlab-reconfigure)
   GitLab for the changes to take effect.

To re-enable impersonation, remove this configuration, and then reconfigure
GitLab.

**For installations from source**

1. Edit the `config/gitlab.yml` file:

   ```yaml
   gitlab:
     impersonation_enabled: false
   ```

1. Save the file, and then [restart](../administration/restart_gitlab.md#installations-from-source)
   GitLab for the changes to take effect.

To re-enable impersonation, remove this configuration, and then restart GitLab.

### Sudo

All API requests support performing an API call as if you were another user,
provided you're authenticated as an administrator with an OAuth or personal
access token that has the `sudo` scope. The API requests are executed with the
permissions of the impersonated user.

As an [administrator](../user/permissions.md), pass the `sudo` parameter either
by using query string or a header with an ID or username (case insensitive) of
the user you want to perform the operation as. If passed as a header, the header
name must be `Sudo`.

If a non administrative access token is provided, GitLab returns an error
message with a status code of `403`:

```json
{
  "message": "403 Forbidden - Must be admin to use sudo"
}
```

If an access token without the `sudo` scope is provided, an error message is
be returned with a status code of `403`:

```json
{
  "error": "insufficient_scope",
  "error_description": "The request requires higher privileges than provided by the access token.",
  "scope": "sudo"
}
```

If the sudo user ID or username cannot be found, an error message is
returned with a status code of `404`:

```json
{
  "message": "404 User with ID or username '123' Not Found"
}
```

Example of a valid API call and a request using cURL with sudo request,
providing a username:

```plaintext
GET /projects?private_token=<your_access_token>&sudo=username
```

```shell
curl --header "PRIVATE-TOKEN: <your_access_token>" --header "Sudo: username" "https://gitlab.example.com/api/v4/projects"
```

Example of a valid API call and a request using cURL with sudo request,
providing an ID:

```plaintext
GET /projects?private_token=<your_access_token>&sudo=23
```

```shell
curl --header "PRIVATE-TOKEN: <your_access_token>" --header "Sudo: 23" "https://gitlab.example.com/api/v4/projects"
```

## Status codes

The API is designed to return different status codes according to context and
action. This way, if a request results in an error, the caller is able to get
insight into what went wrong.

The following table gives an overview of how the API functions generally behave.

| Request type  | Description |
|---------------|-------------|
| `GET`         | Access one or more resources and return the result as JSON. |
| `POST`        | Return `201 Created` if the resource is successfully created and return the newly created resource as JSON. |
| `GET` / `PUT` | Return `200 OK` if the resource is accessed or modified successfully. The (modified) result is returned as JSON. |
| `DELETE`      | Returns `204 No Content` if the resource was deleted successfully. |

The following table shows the possible return codes for API requests.

| Return values            | Description |
|--------------------------|-------------|
| `200 OK`                 | The `GET`, `PUT` or `DELETE` request was successful, and the resource(s) itself is returned as JSON. |
| `204 No Content`         | The server has successfully fulfilled the request, and there is no additional content to send in the response payload body. |
| `201 Created`            | The `POST` request was successful, and the resource is returned as JSON. |
| `304 Not Modified`       | The resource hasn't been modified since the last request. |
| `400 Bad Request`        | A required attribute of the API request is missing. For example, the title of an issue is not given. |
| `401 Unauthorized`       | The user isn't authenticated. A valid [user token](#authentication) is necessary. |
| `403 Forbidden`          | The request isn't allowed. For example, the user isn't allowed to delete a project. |
| `404 Not Found`          | A resource couldn't be accessed. For example, an ID for a resource couldn't be found. |
| `405 Method Not Allowed` | The request isn't supported. |
| `409 Conflict`           | A conflicting resource already exists. For example, creating a project with a name that already exists. |
| `412`                    | The request was denied. This can happen if the `If-Unmodified-Since` header is provided when trying to delete a resource, which was modified in between. |
| `422 Unprocessable`      | The entity couldn't be processed. |
| `429 Too Many Requests`  | The user exceeded the [application rate limits](../administration/instance_limits.md#rate-limits). |
| `500 Server Error`       | While handling the request, something went wrong on the server. |

## Pagination

GitLab supports the following pagination methods:

- Offset-based pagination. This is the default method and is available on all endpoints.
- Keyset-based pagination. Added to selected endpoints but being
  [progressively rolled out](https://gitlab.com/groups/gitlab-org/-/epics/2039).

For large collections, for performance reasons we recommend keyset pagination
(when available) instead of offset pagination.

### Offset-based pagination

Sometimes, the returned result spans many pages. When listing resources, you can
pass the following parameters:

| Parameter  | Description |
|------------|-------------|
| `page`     | Page number (default: `1`). |
| `per_page` | Number of items to list per page (default: `20`, max: `100`). |

In the following example, we list 50 [namespaces](namespaces.md) per page:

```shell
curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/namespaces?per_page=50"
```

#### Pagination `Link` header

[`Link` headers](https://www.w3.org/wiki/LinkHeader) are returned with each
response. They have `rel` set to `prev`, `next`, `first`, or `last` and contain
the relevant URL. Be sure to use these links instead of generating your own URLs.

For GitLab.com users, [some pagination headers may not be returned](../user/gitlab_com/index.md#pagination-response-headers).

In the following cURL example, we limit the output to three items per page
(`per_page=3`) and we request the second page (`page=2`) of [comments](notes.md)
of the issue with ID `8` which belongs to the project with ID `9`:

```shell
curl --head --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/9/issues/8/notes?per_page=3&page=2"
```

The response is:

```http
HTTP/2 200 OK
cache-control: no-cache
content-length: 1103
content-type: application/json
date: Mon, 18 Jan 2016 09:43:18 GMT
link: <https://gitlab.example.com/api/v4/projects/8/issues/8/notes?page=1&per_page=3>; rel="prev", <https://gitlab.example.com/api/v4/projects/8/issues/8/notes?page=3&per_page=3>; rel="next", <https://gitlab.example.com/api/v4/projects/8/issues/8/notes?page=1&per_page=3>; rel="first", <https://gitlab.example.com/api/v4/projects/8/issues/8/notes?page=3&per_page=3>; rel="last"
status: 200 OK
vary: Origin
x-next-page: 3
x-page: 2
x-per-page: 3
x-prev-page: 1
x-request-id: 732ad4ee-9870-4866-a199-a9db0cde3c86
x-runtime: 0.108688
x-total: 8
x-total-pages: 3
```

#### Other pagination headers

GitLab also returns the following additional pagination headers:

| Header          | Description |
|-----------------|-------------|
| `x-next-page`   | The index of the next page. |
| `x-page`        | The index of the current page (starting at 1). |
| `x-per-page`    | The number of items per page. |
| `X-prev-page`   | The index of the previous page. |
| `x-total`       | The total number of items. |
| `x-total-pages` | The total number of pages. |

For GitLab.com users, [some pagination headers may not be returned](../user/gitlab_com/index.md#pagination-response-headers).

### Keyset-based pagination

Keyset-pagination allows for more efficient retrieval of pages and - in contrast
to offset-based pagination - runtime is independent of the size of the
collection.

This method is controlled by the following parameters:

| Parameter    | Description |
|--------------| ------------|
| `pagination` | `keyset` (to enable keyset pagination). |
| `per_page`   | Number of items to list per page (default: `20`, max: `100`). |

In the following example, we list 50 [projects](projects.md) per page, ordered
by `id` ascending.

```shell
curl --request GET --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects?pagination=keyset&per_page=50&order_by=id&sort=asc"
```

The response header includes a link to the next page. For example:

```http
HTTP/1.1 200 OK
...
Links: <https://gitlab.example.com/api/v4/projects?pagination=keyset&per_page=50&order_by=id&sort=asc&id_after=42>; rel="next"
Link: <https://gitlab.example.com/api/v4/projects?pagination=keyset&per_page=50&order_by=id&sort=asc&id_after=42>; rel="next"
Status: 200 OK
...
```

WARNING:
The `Links` header is scheduled to be removed in GitLab 14.0 to be aligned with the
[W3C `Link` specification](https://www.w3.org/wiki/LinkHeader). The `Link`
header was [added in GitLab 13.1](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/33714)
and should be used instead.

The link to the next page contains an additional filter `id_after=42` that
excludes already-retrieved records. The type of filter depends on the
`order_by` option used, and we may have more than one additional filter.

When the end of the collection is reached and there are no additional
records to retrieve, the `Link` header is absent and the resulting array is
empty.

We recommend using only the given link to retrieve the next page instead of
building your own URL. Apart from the headers shown, we don't expose additional
pagination headers.

Keyset-based pagination is supported only for selected resources and ordering
options:

| Resource                | Order |
|-------------------------|-------|
| [Projects](projects.md) | `order_by=id` only. |

## Path parameters

If an endpoint has path parameters, the documentation displays them with a
preceding colon.

For example:

```plaintext
DELETE /projects/:id/share/:group_id
```

The `:id` path parameter needs to be replaced with the project ID, and the
`:group_id` needs to be replaced with the ID of the group. The colons `:`
shouldn't be included.

The resulting cURL call for a project with ID `5` and a group ID of `17` is then:

```shell
curl --request DELETE --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/5/share/17"
```

Path parameters that are required to be URL-encoded must be followed. If not,
it doesn't match an API endpoint and responds with a 404. If there's
something in front of the API (for example, Apache), ensure that it doesn't decode
the URL-encoded path parameters.

## Namespaced path encoding

If using namespaced API calls, make sure that the `NAMESPACE/PROJECT_PATH` is
URL-encoded.

For example, `/` is represented by `%2F`:

```plaintext
GET /api/v4/projects/diaspora%2Fdiaspora
```

A project's _path_ isn't necessarily the same as its _name_. A project's path is
found in the project's URL or in the project's settings, under
**General > Advanced > Change path**.

## File path, branches, and tags name encoding

If a file path, branch or tag contains a `/`, make sure it is URL-encoded.

For example, `/` is represented by `%2F`:

```plaintext
GET /api/v4/projects/1/repository/files/src%2FREADME.md?ref=master
GET /api/v4/projects/1/branches/my%2Fbranch/commits
GET /api/v4/projects/1/repository/tags/my%2Ftag
```

## Request Payload

API Requests can use parameters sent as [query strings](https://en.wikipedia.org/wiki/Query_string)
or as a [payload body](https://tools.ietf.org/html/draft-ietf-httpbis-p3-payload-14#section-3.2).
GET requests usually send a query string, while PUT or POST requests usually
send the payload body:

- Query string:

  ```shell
  curl --request POST "https://gitlab/api/v4/projects?name=<example-name>&description=<example-description>"
  ```

- Request payload (JSON):

  ```shell
  curl --request POST --header "Content-Type: application/json" --data '{"name":"<example-name>", "description":"<example-description"}' "https://gitlab/api/v4/projects"
  ```

URL encoded query strings have a length limitation. Requests that are too large
result in a `414 Request-URI Too Large` error message. This can be resolved by
using a payload body instead.

## Encoding API parameters of `array` and `hash` types

We can call the API with `array` and `hash` types parameters as follows:

### `array`

`import_sources` is a parameter of type `array`:

```shell
curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" \
-d "import_sources[]=github" \
-d "import_sources[]=bitbucket" \
"https://gitlab.example.com/api/v4/some_endpoint"
```

### `hash`

`override_params` is a parameter of type `hash`:

```shell
curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" \
--form "namespace=email" \
--form "path=impapi" \
--form "file=@/path/to/somefile.txt"
--form "override_params[visibility]=private" \
--form "override_params[some_other_param]=some_value" \
"https://gitlab.example.com/api/v4/projects/import"
```

### Array of hashes

`variables` is a parameter of type `array` containing hash key/value pairs
`[{ 'key': 'UPLOAD_TO_S3', 'value': 'true' }]`:

```shell
curl --globoff --request POST --header "PRIVATE-TOKEN: <your_access_token>" \
"https://gitlab.example.com/api/v4/projects/169/pipeline?ref=master&variables[][key]=VAR1&variables[][value]=hello&variables[][key]=VAR2&variables[][value]=world"

curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" \
--header "Content-Type: application/json" \
--data '{ "ref": "master", "variables": [ {"key": "VAR1", "value": "hello"}, {"key": "VAR2", "value": "world"} ] }' \
"https://gitlab.example.com/api/v4/projects/169/pipeline"
```

## `id` vs `iid`

Some resources have two similarly-named fields. For example, [issues](issues.md),
[merge requests](merge_requests.md), and [project milestones](merge_requests.md).
The fields are:

- `id`: ID that is unique across all projects.
- `iid`: Additional, internal ID (displayed in the web UI) that's unique in the
  scope of a single project.

If a resource has both the `iid` field and the `id` field, the `iid` field is
usually used instead of `id` to fetch the resource.

For example, suppose a project with `id: 42` has an issue with `id: 46` and
`iid: 5`. In this case:

- A valid API call to retrieve the issue is `GET /projects/42/issues/5`.
- An invalid API call to retrieve the issue is `GET /projects/42/issues/46`.

Not all resources with the `iid` field are fetched by `iid`. For guidance
regarding which field to use, see the documentation for the specific resource.

## Data validation and error reporting

When working with the API you may encounter validation errors, in which case
the API returns an HTTP `400` error.

Such errors appear in the following cases:

- A required attribute of the API request is missing (for example, the title of
  an issue isn't given).
- An attribute did not pass the validation (for example, the user bio is too
  long).

When an attribute is missing, you receive something like:

```http
HTTP/1.1 400 Bad Request
Content-Type: application/json
{
    "message":"400 (Bad request) \"title\" not given"
}
```

When a validation error occurs, error messages are different. They hold
all details of validation errors:

```http
HTTP/1.1 400 Bad Request
Content-Type: application/json
{
    "message": {
        "bio": [
            "is too long (maximum is 255 characters)"
        ]
    }
}
```

This makes error messages more machine-readable. The format can be described as
follows:

```json
{
    "message": {
        "<property-name>": [
            "<error-message>",
            "<error-message>",
            ...
        ],
        "<embed-entity>": {
            "<property-name>": [
                "<error-message>",
                "<error-message>",
                ...
            ],
        }
    }
}
```

## Unknown route

When you attempt to access an API URL that doesn't exist, you receive a
404 Not Found message.

```http
HTTP/1.1 404 Not Found
Content-Type: application/json
{
    "error": "404 Not Found"
}
```

## Encoding `+` in ISO 8601 dates

If you need to include a `+` in a query parameter, you may need to use `%2B`
instead, due to a [W3 recommendation](http://www.w3.org/Addressing/URL/4_URI_Recommentations.html)
that causes a `+` to be interpreted as a space. For example, in an ISO 8601 date,
you may want to include a specific time in ISO 8601 format, such as:

```plaintext
2017-10-17T23:11:13.000+05:30
```

The correct encoding for the query parameter would be:

```plaintext
2017-10-17T23:11:13.000%2B05:30
```

## Clients

There are many unofficial GitLab API Clients for most of the popular programming
languages. For a complete list, visit the [GitLab website](https://about.gitlab.com/partners/#api-clients).

## Rate limits

For administrator documentation on rate limit settings, see
[Rate limits](../security/rate_limits.md). To find the settings that are
specifically used by GitLab.com, see
[GitLab.com-specific rate limits](../user/gitlab_com/index.md#gitlabcom-specific-rate-limits).