Spring REST API + OAuth2 + AngularJS

1. Overview

In this tutorial, we’ll secure a REST API with OAuth and consume it from a simple AngularJS client.

The application we’re going to build out will consist of four separate modules:

• Authorization Server
• Resource Server
• UI implicit – a front end app using the Implicit Flow
• UI password – a front end app using the Password Flow

2. The Authorization Server

First, let’s start setting up a an Authorization Server as a simple Spring Boot application.

2.1. Maven Configuration

We’ll set up the following set of dependencies:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>    
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
</dependency>  
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>
<dependency>
    <groupId>org.springframework.security.oauth</groupId>
    <artifactId>spring-security-oauth2</artifactId>
    <version>${oauth.version}</version>
</dependency>

Note that we’re using spring-jdbc and MySQL because we’re going to use a JDBC backed implementation of the token store.

2.2. @EnableAuthorizationServer

Now, let’s start configuring the authorization server responsible for managing access tokens:

@Configuration
@EnableAuthorizationServer
public class AuthServerOAuth2Config extends AuthorizationServerConfigurerAdapter {
    @Autowired
    @Qualifier("authenticationManagerBean")
    private AuthenticationManager authenticationManager;

    @Override
    public void configure(AuthorizationServerSecurityConfigurer oauthServer) 
      throws Exception {
        oauthServer.tokenKeyAccess("permitAll()").checkTokenAccess("isAuthenticated()");
    }

    @Override
    public void configure(ClientDetailsServiceConfigurer clients) throws Exception {
        clients.jdbc(dataSource())
               .withClient("sampleClientId")
               .authorizedGrantTypes("implicit")
               .scopes("read")
               .autoApprove(true)
               .and()
               .withClient("clientIdPassword")
               .secret("secret")
               .authorizedGrantTypes("password","authorization_code", "refresh_token")
               .scopes("read");
    }

    @Override
    public void configure(AuthorizationServerEndpointsConfigurer endpoints) 
      throws Exception {
        endpoints.tokenStore(tokenStore()).authenticationManager(authenticationManager);
    }

    @Bean
    public TokenStore tokenStore() {
        return new JdbcTokenStore(dataSource());
    }
}

Note that:

• In order to persist the tokens, we used a JdbcTokenStore
• We registered a client for the “implicit” grant type
• We registered another client and authorized the “password“, “authorization_code” and “refresh_token” grant types
• In order to use the “password” grant type we need to wire in and use the AuthenticationManager bean

2.3. Data Source Configuration

Next, let’s configure our data source to be used by the JdbcTokenStore:

@Value("classpath:schema.sql")
private Resource schemaScript;

@Bean
public DataSourceInitializer dataSourceInitializer(DataSource dataSource) {
    DataSourceInitializer initializer = new DataSourceInitializer();
    initializer.setDataSource(dataSource);
    initializer.setDatabasePopulator(databasePopulator());
    return initializer;
}

private DatabasePopulator databasePopulator() {
    ResourceDatabasePopulator populator = new ResourceDatabasePopulator();
    populator.addScript(schemaScript);
    return populator;
}

@Bean
public DataSource dataSource() {
    DriverManagerDataSource dataSource = new DriverManagerDataSource();
    dataSource.setDriverClassName(env.getProperty("jdbc.driverClassName"));
    dataSource.setUrl(env.getProperty("jdbc.url"));
    dataSource.setUsername(env.getProperty("jdbc.user"));
    dataSource.setPassword(env.getProperty("jdbc.pass"));
    return dataSource;
}

Note: As we are using JdbcTokenStore we need to initialize database schema to create required tables to persist tokens information, so we used DataSourceInitializer – and the following SQL schema:

drop table if exists oauth_client_details;
create table oauth_client_details (
  client_id VARCHAR(255) PRIMARY KEY,
  resource_ids VARCHAR(255),
  client_secret VARCHAR(255),
  scope VARCHAR(255),
  authorized_grant_types VARCHAR(255),
  web_server_redirect_uri VARCHAR(255),
  authorities VARCHAR(255),
  access_token_validity INTEGER,
  refresh_token_validity INTEGER,
  additional_information VARCHAR(4096),
  autoapprove VARCHAR(255)
);

drop table if exists oauth_client_token;
create table oauth_client_token (
  token_id VARCHAR(255),
  token LONG VARBINARY,
  authentication_id VARCHAR(255) PRIMARY KEY,
  user_name VARCHAR(255),
  client_id VARCHAR(255)
);

drop table if exists oauth_access_token;
create table oauth_access_token (
  token_id VARCHAR(255),
  token LONG VARBINARY,
  authentication_id VARCHAR(255) PRIMARY KEY,
  user_name VARCHAR(255),
  client_id VARCHAR(255),
  authentication LONG VARBINARY,
  refresh_token VARCHAR(255)
);

drop table if exists oauth_refresh_token;
create table oauth_refresh_token (
  token_id VARCHAR(255),
  token LONG VARBINARY,
  authentication LONG VARBINARY
);

drop table if exists oauth_code;
create table oauth_code (
  code VARCHAR(255), authentication LONG VARBINARY
);

drop table if exists oauth_approvals;
create table oauth_approvals (
	userId VARCHAR(255),
	clientId VARCHAR(255),
	scope VARCHAR(255),
	status VARCHAR(10),
	expiresAt TIMESTAMP,
	lastModifiedAt TIMESTAMP
);

drop table if exists ClientDetails;
create table ClientDetails (
  appId VARCHAR(255) PRIMARY KEY,
  resourceIds VARCHAR(255),
  appSecret VARCHAR(255),
  scope VARCHAR(255),
  grantTypes VARCHAR(255),
  redirectUrl VARCHAR(255),
  authorities VARCHAR(255),
  access_token_validity INTEGER,
  refresh_token_validity INTEGER,
  additionalInformation VARCHAR(4096),
  autoApproveScopes VARCHAR(255)
);

2.4. Security Configuration

Finally, let’s secure the Authorization Server.

When the client application needs to acquire an Access Token, it will do so after a simple form-login driven auth process:

@Configuration
public class ServerSecurityConfig extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(final AuthenticationManagerBuilder auth) 
      throws Exception {
        auth.inMemoryAuthentication().withUser("john").password("123").roles("USER");
    }

    @Override
    @Bean
    public AuthenticationManager authenticationManagerBean() throws Exception {
        return super.authenticationManagerBean();
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests()
            .antMatchers("/login").permitAll()
            .anyRequest().authenticated()
            .and()
            .formLogin().permitAll();
    }
}

A quick note here is that the form login configuration isn’t necessary for the Password flow – only for the Implicit flow – so you may be able to skip it depending on what OAuth2 flow you’re using.

3. The Resource Server

Now, let’s discuss the resource server; this is essentially the REST API which we ultimately want to be able to consume.

3.1. Maven Configuration

Our Resource Server configuration is the same as the previous Authorization Server application configuration.

3.2. Token Store Configuration

Next, we will configure our TokenStore to access the same database that authorization server use to store access tokens:

@Autowired
private Environment env;

@Bean
public DataSource dataSource() {
    DriverManagerDataSource dataSource = new DriverManagerDataSource();
    dataSource.setDriverClassName(env.getProperty("jdbc.driverClassName"));
    dataSource.setUrl(env.getProperty("jdbc.url"));
    dataSource.setUsername(env.getProperty("jdbc.user"));
    dataSource.setPassword(env.getProperty("jdbc.pass"));
    return dataSource;
}

@Bean
public TokenStore tokenStore() {
    return new JdbcTokenStore(dataSource());
}

Note that, for this simple implementation, we’re sharing the SQL backed token store even though the Authorization and Resource servers are separate applications.

The reason of course is that the Resource Server needs to be able to check the validity of the access tokens issued by the Authorization Server.

3.3. A Sample Controller

Next, let’s implement a simple controller exposing a Foo resource:

@Controller
public class FooController {

    @PreAuthorize("#oauth2.hasScope('read')")
    @RequestMapping(method = RequestMethod.GET, value = "/foos/{id}")
    @ResponseBody
    public Foo findById(@PathVariable long id) {
        return new Foo(Long.parseLong(randomNumeric(2)), randomAlphabetic(4));
    }
}

Note how the client needs the “read” scope to access this Resource.

We also need to enable global method security and configure MethodSecurityExpressionHandler:

@Configuration
@EnableResourceServer
@EnableGlobalMethodSecurity(prePostEnabled = true)
public class OAuth2ResourceServerConfig extends GlobalMethodSecurityConfiguration {

    @Override
    protected MethodSecurityExpressionHandler createExpressionHandler() {
        return new OAuth2MethodSecurityExpressionHandler();
    }
}

And here’s our basic Foo Resource:

public class Foo {
    private long id;
    private String name;
}

3.4. Web Configuration

Finally, let’s set up a very basic web configuration for the API:

@Configuration
@EnableWebMvc
@ComponentScan({ "org.baeldung.web.controller" })
public class ResourceWebConfig extends WebMvcConfigurerAdapter {}

4. Front end – Password Flow

We’re now going to look at a simple front-end AngularJS implementation for the client.

We’re going to be using the OAuth2 Password flow here – which is why this is just a proof of concept not a production ready application. You’ll notice that the client credentials are exposed to the front end – which is something we’ll address in a future article.

Let’s start with the two simple pages – “index” and “login”; once a user provides their credentials, the front-end JS client uses them to acquire an Access Token from Authorization Server.

4.1. Login Page

Here is our simple login page:

<body ng-app="myApp" ng-controller="mainCtrl">
<h1>Login</h1>
<label>Username</label><input ng-model="data.username"/>
<label>Password</label><input type="password" ng-model="data.password"/>
<a href="#" ng-click="login()">Login</a>
</body>

4.2. Obtain Access Token

Now, let’s see how to obtain our access token:

var app = angular.module('myApp', ["ngResource","ngRoute","ngCookies"]);
app.controller('mainCtrl', function($scope, $resource, $http, $httpParamSerializer, $cookies) {
    $scope.data = 
      {grant_type:"password", username: "", password: "", client_id: "clientIdPassword"};
    $scope.encoded = btoa("clientIdPassword:secret");
    
    $scope.login = function() {   
     	var req = {
            method: 'POST',
            url: "http://localhost:8080/spring-security-oauth-server/oauth/token",
            headers: {
                "Authorization": "Basic " + $scope.encoded,
                "Content-type": "application/x-www-form-urlencoded; charset=utf-8"
            },
            data: $httpParamSerializer($scope.data)
        }
        $http(req).then(function(data){
            $http.defaults.headers.common.Authorization= 'Bearer ' + data.data.access_token;
            $cookies.put("access_token", data.data.access_token);
            window.location.href="index";
        });   
   }    
});

Note that:

• To get an Access Token we send a POST to the “/oauth/token” endpoint
• We’re using the client credentials and Basic Auth to hit this endpoint
• We’re then sending the user credentials along with the client id and grant type parameters url encoded
• After we obtain the Access Token – we store it in a cookie

The cookie storage is especially important here, because we’re only using the cookie for storage purposes and not to drive the authentication process directly. This helps protect against cross site request forgery (CSRF) type of attacks and vulnerabilities.

4.3. The Index Page

Here is our simple index page:

<body ng-app="myApp" ng-controller="mainCtrl">
<h1>Foo Details</h1>
<label>ID</label><span>{{foo.id}}</span>
<label>Name</label><span>{{foo.name}}</span>
<a href="#" ng-click="getFoo()">New Foo</a>
</body>

4.4. Authorize Client Requests

As we will need to authorize our requests to the resource using our access token, we will append a simple authorization header with access token:

var isLoginPage = window.location.href.indexOf("login") != -1;
if(isLoginPage){
    if($cookies.get("access_token")){
        window.location.href = "index";
    }
}else{
    if($cookies.get("access_token")){
        $http.defaults.headers.common.Authorization= 'Bearer ' + $cookies.get("access_token");
    }else{
        window.location.href = "login";
    }
}

If no cookie is found, the user will be redirected to login page.

5. Front End – Implicit Grant

Now, let’s take a look at our client application that use implicit grant.

Our client application is a separated module that try to access resources server after obtaining access token from authorization server using implicit grant flow.

5.1. Maven Configuration

Here is pom.xml dependencies:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>

Note: we didn’t need OAuth dependency – as we will handle it using AngularJS directive OAuth-ng which can connect to OAuth2 server with implicit grant flow.

5.2. Web Configuration

And here is our simple web configuration:

@Configuration
@EnableWebMvc
public class UiWebConfig extends WebMvcConfigurerAdapter {
    @Bean
    public static PropertySourcesPlaceholderConfigurer 
      propertySourcesPlaceholderConfigurer() {
        return new PropertySourcesPlaceholderConfigurer();
    }

    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }

    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        super.addViewControllers(registry);
        registry.addViewController("/index");
        registry.addViewController("/oauthTemplate");
    }

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/resources/**").addResourceLocations("/resources/");
    }
}

5.3. The Home Page

Next, here is our home page:

OAuth-ng directive needs:

• site: authorization server URL
• client-id: application client id
• redirect-uri: the URI to be redirected to after obtaining access token from authorization server
• scope: privilege requested from Authorization Server
• template: rendered custom html template

<body ng-app="myApp" ng-controller="mainCtrl">
<oauth
  site="http://localhost:8080/spring-security-oauth-server"
  client-id="clientId"
  redirect-uri="http://localhost:8080/spring-security-oauth-ui-implicit/index"
  scope="read"
  template="oauthTemplate">
</oauth>

<h1>Foo Details</h1>
<label >ID</label><span>{{foo.id}}</span>
<label>Name</label><span>{{foo.name}}</span>
</div>
<a href="#" ng-click="getFoo()">New Foo</a>

<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular-resource.min.js">
</script>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular-route.min.js">
</script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/ngStorage/0.3.9/ngStorage.min.js"></script>
<script th:src="@{/resources/oauth-ng.js}"></script>
</body>

Note how we’re using the OAuth-ng directive to obtain the Access Token.

Also, here’s the simple oauthTemplate.html:

<div>
  <a href="#" ng-show="show=='logged-out'" ng-click="login()">Login</a>
  <a href="#" ng-show="show=='denied'" ng-click="login()">Access denied. Try again.</a>
</div>

5.4. AngularJS App

And here is our AngularJS app:

var app = angular.module('myApp', ["ngResource","ngRoute","oauth"]);
app.config(function($locationProvider) {
  $locationProvider.html5Mode({
      enabled: true,
      requireBase: false
    }).hashPrefix('!');
});

app.controller('mainCtrl', function($scope,$resource,$http) {
    $scope.$on('oauth:login', function(event, token) {
        $http.defaults.headers.common.Authorization= 'Bearer ' + token.access_token;
    });

    $scope.foo = {id:0 , name:"sample foo"};
    $scope.foos = $resource(
      "http://localhost:8080/spring-security-oauth-resource/foos/:fooId", {fooId:'@id'});
    $scope.getFoo = function(){
        $scope.foo = $scope.foos.get({fooId:$scope.foo.id});
    } 
});

Note how, after obtaining the Access Token, we’re using it via the Authorization header whenever we consume protected resources from within the Resource Server.

6. Conclusion

We learned how to authorize our application using OAuth2.