gitlab-org--gitlab-foss/doc/development/documentation/restful_api_styleguide.md

type	stage	group	info	description
reference, dev	none	Development	See the Technical Writers assigned to Development Guidelines: https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments-to-development-guidelines	Writing styles, markup, formatting, and other standards for GitLab's RESTful APIs.

RESTful API

REST API resources are documented in Markdown under /doc/api. Each resource has its own Markdown file, which is linked from api_resources.md.

When modifying the Markdown, also update the corresponding OpenAPI definition if one exists for the resource. If not, consider creating one. Match the latest OpenAPI 3.0.x specification. (For more information, see the discussion in this issue.)

In the Markdown doc for a resource (AKA endpoint):

• Every method must have the REST API request. For example:

  GET /projects/:id/repository/branches
  

• Every method must have a detailed description of the parameters.

• Every method must have a cURL example.

• Every method must have a response body (in JSON format).

API topic template

The following can be used as a template to get started:

## Descriptive title

One or two sentence description of what endpoint does.

```plaintext
METHOD /endpoint
```

| Attribute   | Type     | Required | Description           |
|:------------|:---------|:---------|:----------------------|
| `attribute` | datatype | yes/no   | Detailed description. |
| `attribute` | datatype | yes/no   | Detailed description. |

Example request:

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

Example response:

```json
[
  {
  }
]
```

Method description

Use the following table headers to describe the methods. Attributes should always be in code blocks using backticks (`).

| Attribute | Type | Required | Description |
|:----------|:-----|:---------|:------------|

Rendered example:

Attribute	Type	Required	Description
user	string	yes	The GitLab username.

cURL commands

• Use https://gitlab.example.com/api/v4/ as an endpoint.
• Wherever needed use this personal access token: <your_access_token>.
• Always put the request first. GET is the default so you don't have to include it.
• Wrap the URL in double quotes (").
• Prefer to use examples using the personal access token and don't pass data of username and password.

Methods	Description
--header "PRIVATE-TOKEN: <your_access_token>"	Use this method as is, whenever authentication needed.
--request POST	Use this method when creating new objects
--request PUT	Use this method when updating existing objects
--request DELETE	Use this method when removing existing objects

cURL Examples

The following sections include a set of cURL examples you can use in the API documentation.

CAUTION: Caution: Do not use information for real users, URLs, or tokens. For documentation, refer to our relevant style guide sections on Fake user information, Fake URLs, and Fake tokens.

Simple cURL command

Get the details of a group:

curl --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/groups/gitlab-org"

cURL example with parameters passed in the URL

Create a new project under the authenticated user's namespace:

curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects?name=foo"

Post data using cURL's --data

Instead of using --request POST and appending the parameters to the URI, you can use cURL's --data option. The example below will create a new project foo under the authenticated user's namespace.

curl --data "name=foo" --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects"

Post data using JSON content

This example creates a new group. Be aware of the use of single (') and double (") quotes.

curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" --header "Content-Type: application/json" --data '{"path": "my-group", "name": "My group"}' "https://gitlab.example.com/api/v4/groups"

For readability, you can also set up the --data by using the following format:

curl --request POST \
--url "https://gitlab.example.com/api/v4/groups" \
--header "content-type: application/json" \
--header "PRIVATE-TOKEN: <your_access_token>" \
--data '{
  "path": "my-group",
  "name": "My group"
}'

Post data using form-data

Instead of using JSON or urlencode you can use multipart/form-data which properly handles data encoding:

curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" --form "title=ssh-key" --form "key=ssh-rsa AAAAB3NzaC1yc2EA..." "https://gitlab.example.com/api/v4/users/25/keys"

The above example is run by and administrator and will add an SSH public key titled ssh-key to user's account which has an ID of 25.

Escape special characters

Spaces or slashes (/) may sometimes result to errors, thus it is recommended to escape them when possible. In the example below we create a new issue which contains spaces in its title. Observe how spaces are escaped using the %20 ASCII code.

curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/42/issues?title=Hello%20Dude"

Use %2F for slashes (/).

Pass arrays to API calls

The GitLab API sometimes accepts arrays of strings or integers. For example, to exclude specific users when requesting a list of users for a project, you would do something like this:

curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" --data "skip_users[]=<user_id>" --data "skip_users[]=<user_id>" "https://gitlab.example.com/api/v4/projects/<project_id>/users"