Add authentication for data source plugins

Grafana plugins can perform authenticated requests against a third-party API by using the data source proxy or through a custom a backend plugin.

Choose an authentication method

Configure your data source plugin to authenticate against a third-party API in one of either of two ways:

• Use the data source proxy method, or
• Build a backend plugin.

Case	Use
Do you need to authenticate your plugin using Basic Auth or API keys?	Use the data source proxy.
Does your API support OAuth 2.0 using client credentials?	Use the data source proxy.
Does your API use a custom authentication method that isn't supported by the data source proxy?	Use a backend plugin.
Does your API communicate over a protocol other than HTTP?	Use a backend plugin.
Does your plugin require alerting support?	Use a backend plugin.

Encrypt data source configuration

Data source plugins have two ways of storing custom configuration: jsonData and secureJsonData.

Users with the Viewer role can access data source configuration such as the contents of jsonData in cleartext. If you've enabled anonymous access, anyone who can access Grafana in their browser can see the contents of jsonData.

Users of Grafana Enterprise can restrict access to data sources to specific users and teams. For more information, refer to Data source permissions.

You can see the settings that the current user has access to by entering window.grafanaBootData in the developer console of your browser.

warning

Do not use jsonData with sensitive data such as passwords, tokens, and API keys. If you need to store sensitive information, use secureJsonData instead.

Store configuration in secureJsonData

If you need to store sensitive information, use secureJsonData instead of jsonData. Whenever the user saves the data source configuration, the secrets in secureJsonData are sent to the Grafana server and they're encrypted before they're stored.

Once you have encrypted the secure configuration, it can no longer be accessed from the browser. The only way to access secrets after they've been saved is by using the data source proxy.

Add secrets configuration to your data source plugin

To add secrets to a data source plugin, you can add support for configuring an API key.

1. Create a new interface in types.ts to hold the API key:

   export interface MySecureJsonData {
     apiKey?: string;
   }

2. Add type information to your secureJsonData object by updating the props for your ConfigEditor to accept the interface as a second type parameter. Access the value of the secret from the options prop inside your ConfigEditor:

   interface Props extends DataSourcePluginOptionsEditorProps<MyDataSourceOptions, MySecureJsonData> {}

   const { secureJsonData, secureJsonFields } = options;
   const { apiKey } = secureJsonData;
   note

   You can do this until the user saves the configuration; when the user saves the configuration, Grafana clears the value. After that, you can use secureJsonFields to determine whether the property has been configured.

3. To securely update the secret in your plugin's configuration editor, update the secureJsonData object using the onOptionsChange prop:

   const onAPIKeyChange = (event: ChangeEvent<HTMLInputElement>) => {
     onOptionsChange({
       ...options,
       secureJsonData: {
         apiKey: event.target.value,
       },
     });
   };

4. Define a component that can accept user input:

   <Input
     type="password"
     placeholder={secureJsonFields?.apiKey ? 'configured' : ''}
     value={secureJsonData.apiKey ?? ''}
     onChange={onAPIKeyChange}
   />

5. Optional: If you want the user to be able to reset the API key, then you need to set the property to false in the secureJsonFields object:

   const onResetAPIKey = () => {
     onOptionsChange({
       ...options,
       secureJsonFields: {
         ...options.secureJsonFields,
         apiKey: false,
       },
       secureJsonData: {
         ...options.secureJsonData,
         apiKey: '',
       },
     });
   };

Once users can configure secrets, the next step is to see how we can add them to our requests.

Authenticate using the data source proxy

Once the user has saved the configuration for a data source, the secret data source configuration will no longer be available in the browser. Encrypted secrets can only be accessed on the server. So how do you add them to your request?

The Grafana server comes with a proxy that lets you define templates for your requests: proxy routes. Grafana sends the proxy route to the server, decrypts the secrets along with other configuration, and adds them to the request before sending it.

note

Be sure not to confuse the data source proxy with the auth proxy. The data source proxy is used to authenticate a data source, while the auth proxy is used to log into Grafana itself.

Add a proxy route to your plugin

To forward requests through the Grafana proxy, you need to configure one or more proxy routes. A proxy route is a template for any outgoing request that is handled by the proxy. You can configure proxy routes in the plugin.json file.

1. Add the route to plugin.json:

   src/plugin.json

   "routes": [
     {
       "path": "example",
       "url": "https://api.example.com"
     }
   ]
   note

   You need to build your plugin and restart the Grafana server every time you make a change to your plugin.json file.

2. In the DataSource, extract the proxy URL from instanceSettings to a class property called url:

   export class DataSource extends DataSourceApi<MyQuery, MyDataSourceOptions> {
     url?: string;
   
     constructor(instanceSettings: DataSourceInstanceSettings<MyDataSourceOptions>) {
       super(instanceSettings);
   
       this.url = instanceSettings.url;
     }
   
     // ...
   }

3. In the query method, make a request using BackendSrv. The first section of the URL path needs to match the path of your proxy route. The data source proxy replaces this.url + routePath with the url of the route. Based on our example, the URL for the request would be https://api.example.com/v1/users:

   import { getBackendSrv } from '@grafana/runtime';

   const routePath = '/example';
   
   getBackendSrv().datasourceRequest({
     url: this.url + routePath + '/v1/users',
     method: 'GET',
   });

Add a dynamic proxy route to your plugin

Grafana sends the proxy route to the server, where the data source proxy decrypts any sensitive data and interpolates the template variables with the decrypted data before making the request.

To add user-defined configuration to your routes:

• Use .JsonData for configuration stored in jsonData. For example, where projectId is the name of a property in the jsonData object:

  src/plugin.json

  "routes": [
    {
      "path": "example",
      "url": "https://api.example.com/projects/{{ .JsonData.projectId }}"
    }
  ]

• Use .SecureJsonData for sensitive data stored in secureJsonData. For example, where password is the name of a property in the secureJsonData object:

  src/plugin.json

  "routes": [
    {
      "path": "example",
      "url": "https://{{ .JsonData.username }}:{{ .SecureJsonData.password }}@api.example.com"
    }
  ]

In addition to adding the URL to the proxy route, you can also add headers, URL parameters, and a request body.

Add HTTP headers to a proxy route

Here's an example of adding name and content as HTTP headers:

src/plugin.json

"routes": [
  {
    "path": "example",
    "url": "https://api.example.com",
    "headers": [
      {
        "name": "Authorization",
        "content": "Bearer {{ .SecureJsonData.apiToken }}"
      }
    ]
  }
]

Add URL parameters to a proxy route

Here's an example of adding name and content as URL parameters:

src/plugin.json

"routes": [
  {
    "path": "example",
    "url": "http://api.example.com",
    "urlParams": [
      {
        "name": "apiKey",
        "content": "{{ .SecureJsonData.apiKey }}"
      }
    ]
  }
]

note

Be aware that urlParams configuration is only supported in data source plugins. It is not supported in app plugins.

Add a request body to a proxy route

Here's an example of adding username and password to the request body:

src/plugin.json

"routes": [
  {
    "path": "example",
    "url": "http://api.example.com",
    "body": {
      "username": "{{ .JsonData.username }}",
      "password": "{{ .SecureJsonData.password }}"
    }
  }
]

Add an OAuth 2.0 proxy route to your plugin

Since your request to each route is made server-side with OAuth 2.0 authentication, only machine-to-machine requests are supported. In order words, if you need to use a different grant than client credentials, you need to implement it yourself.

To authenticate using OAuth 2.0, add a tokenAuth object to the proxy route definition. If necessary, Grafana performs a request to the URL defined in tokenAuth to retrieve a token before making the request to the URL in your proxy route. Grafana automatically renews the token when it expires.

Any parameters defined in tokenAuth.params are encoded as application/x-www-form-urlencoded and sent to the token URL.

src/plugin.json

{
  "routes": [
    {
      "path": "api",
      "url": "https://api.example.com/v1",
      "tokenAuth": {
        "url": "https://api.example.com/v1/oauth/token",
        "params": {
          "grant_type": "client_credentials",
          "client_id": "{{ .SecureJsonData.clientId }}",
          "client_secret": "{{ .SecureJsonData.clientSecret }}"
        }
      }
    }
  ]
}

note

Be aware that tokenAuth configuration is only supported in data source plugins. It is not supported in app plugins.

Authenticate using a backend plugin

While the data source proxy supports the most common authentication methods for HTTP APIs, using proxy routes has a few limitations:

• Proxy routes only support HTTP or HTTPS.
• Proxy routes don't support custom token authentication.

If any of these limitations apply to your plugin, you need to add a backend plugin. Because backend plugins run on the server, they can access decrypted secrets, which makes it easier to implement custom authentication methods.

The decrypted secrets are available from the DecryptedSecureJSONData field in the instance settings.

func (ds *dataSource) QueryData(ctx context.Context, req *backend.QueryDataRequest) (*backend.QueryDataResponse, error) {
  instanceSettings := req.PluginContext.DataSourceInstanceSettings

  if apiKey, exists := instanceSettings.DecryptedSecureJSONData["apiKey"]; exists {
    // Use the decrypted API key.
  }

  // ...
}

Forward OAuth identity for the logged-in user

If your data source uses the same OAuth provider as Grafana itself, for example, using generic OAuth authentication, then your data source plugin can reuse the access token for the logged-in Grafana user.

To allow Grafana to pass the access token to the plugin, update the data source configuration and set the jsonData.oauthPassThru property to true. The DataSourceHttpSettings settings provide a toggle, the Forward OAuth Identity option, for this. You can also build an appropriate toggle to set jsonData.oauthPassThru in your data source configuration page UI.

When configured, Grafana can forward authorization HTTP headers such as Authorization or X-ID-Token to a backend data source. This information is available across the QueryData, CallResource and CheckHealth requests.

To get Grafana to forward the headers, create an HTTP client using the Grafana plugin SDK for Go and set the ForwardHTTPHeaders option to true (by default, it's set to false). This package exposes request information which can be subsequently forwarded downstream or used directly within the plugin, or both.

func NewDatasource(ctx context.Context, settings backend.DataSourceInstanceSettings) (instancemgmt.Instance, error) {
  opts, err := settings.HTTPClientOptions(ctx)
	if err != nil {
		return nil, fmt.Errorf("http client options: %w", err)
	}

    // Important: Reuse the same client for each query to avoid using all available connections on a host.

  opts.ForwardHTTPHeaders = true

	cl, err := httpclient.New(opts)
	if err != nil {
		return nil, fmt.Errorf("httpclient new: %w", err)
	}
	return &Datasource{
		httpClient: cl,
	}, nil
}

func (ds *dataSource) QueryData(ctx context.Context, req *backend.QueryDataRequest) (*backend.QueryDataResponse, error) {
    // Necessary to keep the Context, since the injected middleware is configured there
    req, err := http.NewRequestWithContext(ctx, http.MethodGet, "https://some-url", nil)
    if err != nil {
      return nil, fmt.Errorf("new request with context: %w", err)
    }
    // Authorization header is automatically injected if oauthPassThru is configured
    resp, err := ds.httpClient.Do(req)
    // ...
}

You can see a full working plugin example here: datasource-http-backend.

Extract a header from an HTTP request

If you need to access the HTTP header information directly, you can also extract that information from the request:

func (ds *dataSource) CheckHealth(ctx context.Context, req *backend.CheckHealthRequest) (*backend.CheckHealthResult, error) {
  token := strings.Fields(req.GetHTTPHeader(backend.OAuthIdentityTokenHeaderName))
  var (
    tokenType   = token[0]
    accessToken = token[1]
  )
  idToken := req.GetHTTPHeader(backend.OAuthIdentityIDTokenHeaderName) // present if user's token includes an ID token

  // ...
  return &backend.CheckHealthResult{Status: backend.HealthStatusOk}, nil
}

func (ds *dataSource) QueryData(ctx context.Context, req *backend.QueryDataRequest) (*backend.QueryDataResponse, error) {
  token := strings.Fields(req.GetHTTPHeader(backend.OAuthIdentityTokenHeaderName))
  var (
    tokenType   = token[0]
    accessToken = token[1]
  )
  idToken := req.GetHTTPHeader(backend.OAuthIdentityIDTokenHeaderName)

  for _, q := range req.Queries {
    // ...
  }
}

func (ds *dataSource) CallResource(ctx context.Context, req *backend.CallResourceRequest, sender backend.CallResourceResponseSender) error {
  token := req.GetHTTPHeader(backend.OAuthIdentityTokenHeaderName)
  idToken := req.GetHTTPHeader(backend.OAuthIdentityIDTokenHeaderName)

  // ...
}

Work with cookies

Forward cookies for the logged-in user

Your data source plugin can forward cookies for the logged-in Grafana user to the data source. Use the DataSourceHttpSettings component on the data source's configuration page. It provides the Allowed cookies option, where you can specify the cookie names.

When configured, as with authorization headers, these cookies are automatically injected if you use the SDK HTTP client.

Extract cookies for the logged-in user

You can also extract the cookies in the QueryData, CallResource, and CheckHealth requests if required.

QueryData

func (ds *dataSource) QueryData(ctx context.Context, req *backend.QueryDataRequest) (*backend.QueryDataResponse, error) {
  cookies:= req.GetHTTPHeader(backend.CookiesHeaderName)

  // ...
}

CallResource

func (ds *dataSource) CallResource(ctx context.Context, req *backend.CallResourceRequest, sender backend.CallResourceResponseSender) error {
  cookies:= req.GetHTTPHeader(backend.CookiesHeaderName)

  // ...
}

CheckHealth

func (ds *dataSource) CheckHealth(ctx context.Context, req *backend.CheckHealthRequest) (*backend.CheckHealthResult, error) {
  cookies:= req.GetHTTPHeader(backend.CookiesHeaderName)

  // ...
}

Forward user header for the logged-in user

When send_user_header is enabled, Grafana passes the user header to the plugin using the X-Grafana-User header. You can forward this header as well as authorization headers or configured cookies.

QueryData

Forward the QueryData header like this:

func (ds *dataSource) QueryData(ctx context.Context, req *backend.QueryDataRequest) (*backend.QueryDataResponse, error) {
  u := req.GetHTTPHeader("X-Grafana-User")

  // ...
}

CallResource

Forward the CallResource header like this:

func (ds *dataSource) CallResource(ctx context.Context, req *backend.CallResourceRequest, sender backend.CallResourceResponseSender) error {
  u := req.GetHTTPHeader("X-Grafana-User")

  // ...
}

CheckHealth

Forward the CheckHealth header like this:

func (ds *dataSource) CheckHealth(ctx context.Context, req *backend.CheckHealthRequest) (*backend.CheckHealthResult, error) {
  u := req.GetHTTPHeader("X-Grafana-User")

  // ...
}