grafana/pkg/api/README.md

OpenAPI specifications

Since version 8.4, HTTP API details are specified using OpenAPI v2. Starting from version 9.1, there is also an OpenAPI v3 specification (generated by the v2 one using this script).

OpenAPI annotations

The OpenAPI v2 specification is generated automatically from the annotated Go code using go-swagger which scans the source code for annotation rules. Refer to this getting started guide for getting familiar with the toolkit.

Developers modifying the HTTP API endpoints need to make sure to add the necessary annotations so that their changes are reflected into the generated specifications.

Example of endpoint annotation

The following route defines a PATCH endpoint under the /serviceaccounts/{serviceAccountId} path with tag service_accounts (used for grouping together several routes) and operation ID updateServiceAccount (used for uniquely identifying routes and associate parameters and response with them).

// swagger:route PATCH /serviceaccounts/{serviceAccountId} service_accounts updateServiceAccount
//
// # Update service account
//
// Required permissions (See note in the [introduction](https://grafana.com/docs/grafana/latest/developers/http_api/serviceaccount/#service-account-api) for an explanation):
// action: `serviceaccounts:write` scope: `serviceaccounts:id:1` (single service account)
//
// Responses:
// 200: updateServiceAccountResponse
// 400: badRequestError
// 401: unauthorisedError
// 403: forbiddenError
// 404: notFoundError
// 500: internalServerError

The go-swagger can discover such annotations by scanning any code imported by pkg/server but by convention we place the endpoint annotations above the endpoint definition.

Example of endpoint parameters

The following struct defines the route parameters for the updateServiceAccount endpoint. The route expects:

• a path parameter denoting the service account identifier and
• a body parameter with the new values for the specific service account

// swagger:parameters updateServiceAccount
type UpdateServiceAccountParams struct {
	// in:path
	ServiceAccountId int64 `json:"serviceAccountId"`
	// in:body
	Body serviceaccounts.UpdateServiceAccountForm
}

Example of endpoint response

The following struct defines the response for the updateServiceAccount endpoint in case of a successful 200 response.

// swagger:response updateServiceAccountResponse
type UpdateServiceAccountResponse struct {
	// in:body
	Body struct {
		Message        string                                    `json:"message"`
		ID             int64                                     `json:"id"`
		Name           string                                    `json:"name"`
		ServiceAccount *serviceaccounts.ServiceAccountProfileDTO `json:"serviceaccount"`
	}
}

OpenAPI generation

Developers can re-create the OpenAPI v2 and v3 specifications using the following command:

make clean-api-spec && make openapi3-gen

They can observe its output into the public/api-merged.json and public/openapi3.json files.

Finally, they can browser and try out both the OpenAPI v2 and v3 via the Swagger UI editor (served by the grafana server) by navigating to /swagger-ui and /openapi3 respectivally.