This plugin is an OAuth2 Provider based on the Spring Security OAuth libraries. It is partially based off of Burt Beckwith's OAuth Provider plugin, which was never officially released.

While this plugin works for certain use cases, not all OAuth2 flows have been tested. In particular, the following works and has been tested:

• The full flow of logging in with both users and clients using tokens and authorization codes

However, the following items have not been tested and may or may not work:

• Grant types besides authorization_code and client_credentials
• Protected resources via Spring OAuth2 ** This is currently done with the Spring Security core methods (ie request maps, annotations, intercept maps)

Setup

On install, a view is created at grails-app/views/oauth/confirm.gsp. This view may be modified as desired, but the location should match the userApprovalEndpointUrl setting discussed below.

How to Use

Register Clients in Configuration

Clients are configured using the default in memory client details service in an option in Config.groovy or an external configuration file specified by grails.config.locations. The following is an example of configuring a simple client with an ID of myId and a secret key of mySecret:

grails.plugins.springsecurity.oauthProvider.clients = [
	[
		clientId:"myId",
		clientSecret:"mySecret"
	]
]

Notice that the client configuration consists of a list of maps with each map representing a single configured client. The properties which can be configured match the properties in the org.springframework.security.oauth2.provider.BaseClientDetails class. The only difference is the webServerRedirectUri has been renamed to registeredRedirectUri in order to be compatible with newer releases of Spring Security OAuth2. Default values have been configured for each property except for clientId and clientSecret since these are unique for each configured client. These default values are shown in the following code block with their default values. These default values may be modified by placing a line similar to the following in Config.groovy or an external configuration file.

grails.plugins.springsecurity.oauthProvider.defaultClientConfig.resourceIds = []
grails.plugins.springsecurity.oauthProvider.defaultClientConfig.authorizedGrantTypes = ["authorization_code", "refresh_token"]
grails.plugins.springsecurity.oauthProvider.defaultClientConfig.scope = []
grails.plugins.springsecurity.oauthProvider.defaultClientConfig.registeredRedirectUri = null
grails.plugins.springsecurity.oauthProvider.defaultClientConfig.authorities = []

For example, with a default configuration option in Config.groovy of:

grails.plugins.springsecurity.oauthProvider.defaultClientConfig.authorizedGrantTypes = ["implicit"]

And a client configuration of:

grails.plugins.springsecurity.oauthProvider.clients = [
	[
		clientId:"myId",
		clientSecret:"mySecret"
	]
]

Will result in a client with an ID of myId and a single authorized grant type of implicit. However, if the client configuration was modified to the following:

grails.plugins.springsecurity.oauthProvider.clients = [
	[
		clientId:"myId",
		clientSecret:"mySecret",
		authorizedGrantTypes:["authorization_code"]
	]
]

Then the resulting configured client myId would have a single authorized grant type of authorization_code. In other words, the default configuration is overridden by the individual client configuration.

Using this method, when the configuration changes, the entire list of clients is reloaded and replaces the old list.

Registering Clients in Bootstrap

Clients may also be individually registered by using the BaseClientDetails class in combination with the clientDetailsService bean in the Bootstrap process. The following is an example of registering a client programmatically (to be run in the BootStrap of your application):

import org.springframework.security.oauth2.provider.BaseClientDetails;

class BootStrap {
	def clientDetailsService
	
	def init = { servletContext ->
		def client = new BaseClientDetails()
		client.clientId = "clientId"
		client.clientSecret = "clientSecret"
		client.authorizedGrantTypes = ["authorization_code", "refresh_token", "client_credentials", "password", "implicit"]
		
		// Set the full contents of the client details service store to the newly created client
		clientDetailsService.clientDetailsStore = [
			// Map of client ID to the client details instance
			"clientId":client
		]
	}

Login Flows

Client Login

The client may login with the URL given in the tokenEndpointUrl setting (/oauth/token by default) by using the following syntax. Notice the grant_type of client_credentials and that the client credentials from the example above are used.

http://localhost:8080/app/oauth/token?grant_type=client_credentials&client_id=clientId&client_secret=clientSecret

The response from a login such as this is the following JSON. The access_token is the important piece here.

{
  "access_token": "449acfe6-663f-4fde-b1f8-414c867a4cb5",
  "expires_in": 43200,
  "refresh_token": "ab12ce7a-de9d-48db-a674-0044897074b0"
}

User Approval of Clients

The following URLs or configuration options show a typical flow authorizing a client for a certain user.

• The client must first be logged in using the URL above.
• Separately, the client must be logged into the application protected by this plugin. Alternatively, they will be logged in on the next step since the authorizationEndpointUrl must be protected with Spring Security Core. One way to accomplish this is to use the static rules in Config.groovy:

grails.plugins.springsecurity.controllerAnnotations.staticRules = [
	'/oauth/authorize.dispatch':['ROLE_ADMIN'],
]

** Note that the URL is mapped with .dispatch at the end. This is essential in order to correctly protect the resource. For example, a authorizationEndpointUrl of /custom/authorize-oauth2 would need to be protected with /custom/authorize-oauth2.dispatch.

• A client attempting to use a service provided by the OAuth protected application is reached by a user. The client then redirects the user to the authorizationEndpointUrl setting (/oauth/authorize by default). This will actually redirect the user to the userApprovalEndpointUrl setting which will present the user with an option to authorize or deny access to the application for the client.

http://localhost:8080/app/oauth/authorize?response_type=code&client_id=clientId&redirect_uri=http://localhost:8080/app/

The user will then be redirected to the redirect_uri with the code appended as a URL parameter such as:

http://localhost:8080/app/?code=YjZOa8

• The client captures this code and sends it to the application at the authorizationEndpointUrl setting.
  This will allow the client to access the application as the user. Notice the grant_type of authorization_code this time.

http://localhost:8080/app/oauth/authorize?grant_type=authorization_code&client_id=clientId&code=OVD8SZ&redirect_uri=http://localhost:8080/app/

This will then give a token to the client that can be used to access the application as the user (an example needs to go here).

NOTE: The redirect_uri in the code response and the authorization_code grant must match! Otherwise, the authorization will fail.

Protecting Resources

If the instructions above are followed, this plugin will provide access to resources protected with the Secured annotation or with static rules defined in Config.groovy. Resources protected with request maps or other spring security configurations should be protected, but is untested. If you have tested this plugin in these configurations, please let me know and I'll update this section.

Configuration

Endpoint URLs

By default, three endpoint URLs have been defined. Note that default URLMappings are provided for the authorizationEndpointUrl and the tokenEndpointUrl. If these are modified, additional URLMappings will have to be set. Their default values and how they would be set in Config.groovy are shown below:

grails.plugins.springsecurity.oauthProvider.authorizationEndpointUrl = "/oauth/authorize"
grails.plugins.springsecurity.oauthProvider.tokenEndpointUrl = "/oauth/token"	// Where the client is authorized
grails.plugins.springsecurity.oauthProvider.userApprovalEndpointUrl = "/oauth/confirm"	// Where the user confirms that they approve the client

NOTE: The userApprovalEndpointUrl never is actually redirected to, but is simply used to specify the location of the view. For example, a userApprovalEndpointUrl of /custom/oauth_confirm would map to the grails-app/views/custom/oauth_confirm.gsp view.

Grant Types

The grant types for OAuth authentication may be enabled or disabled with simple configuration options. By default all grant types are enabled. Set the option to false to disable it completely, regardless of client configuration.

grails.plugins.springsecurity.oauthProvider.grantTypes.authorizationCode = true
grails.plugins.springsecurity.oauthProvider.grantTypes.implicit = true
grails.plugins.springsecurity.oauthProvider.grantTypes.refreshToken = true
grails.plugins.springsecurity.oauthProvider.grantTypes.clientCredentials = true
grails.plugins.springsecurity.oauthProvider.grantTypes.password = true

Configuration

Here are some other configuration options that can be set and their default values. Again, these would be placed in Config.groovy:

grails.plugins.springsecurity.oauthProvider.active = true // Set to false to disable the provider, true in all environments but test where false is the default
grails.plugins.springsecurity.oauthProvider.filterStartPosition = SecurityFilterPosition.EXCEPTION_TRANSLATION_FILTER.order // The starting location of the filters registered
grails.plugins.springsecurity.oauthProvider.authorizationCode.approvalParameterName = "user_oauth_approval" // Used on the user confirmation page (see userApprovalEndpointUrl)
grails.plugins.springsecurity.oauthProvider.tokenServices.refreshTokenValiditySeconds = 60 * 10 //default 10 minutes
grails.plugins.springsecurity.oauthProvider.tokenServices.accessTokenValiditySeconds = 60 * 60 * 12 //default 12 hours
grails.plugins.springsecurity.oauthProvider.tokenServices.reuseRefreshToken = true
grails.plugins.springsecurity.oauthProvider.tokenServices.supportRefreshToken = true