REST API (v4.5)
pac4j allows you to validate users via a REST API.
1) Dependency
You need to use the following module: pac4j-http.
Example (Maven dependency):
<dependency>
    <groupId>org.pac4j</groupId>
    <artifactId>pac4j-http</artifactId>
    <version>${pac4j.version}</version>
</dependency>
2) RestAuthenticator
The RestAuthenticator validates the provided username/password by POSTing them as a basic authentication to an URL which must return:
- 
    
a 200 HTTP response with a user profile as a JSON if the username/password credentials are valid
 - 
    
any other HTTP status code (preferably 401) if the username/password credentials are not valid.
 
In case of a successful authentication, a RestProfile is returned.
Example of a correct server response:
{
  "id": "1234",
  "attributes": {
    "firstName": "Jerome"
  }
}
Example of a client:
RestAuthenticator authenticator = new RestAuthenticator("http://rest-api-url");
DirectBasicAuthClient directBasicAuthClient = new DirectBasicAuthClient(authenticator);