Created class FacebookUtils, that configures the added extensions

diff --git a/src/main/java/de/juplo/facebook/FacebookUtils.java b/src/main/java/de/juplo/facebook/FacebookUtils.java
new file mode 100644 (file)
index 0000000..bf0a5df
--- /dev/null
+++ b/src/main/java/de/juplo/facebook/FacebookUtils.java
@@ -0,0 +1,132 @@
+package de.juplo.facebook;
+
+
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.List;
+import javax.annotation.PostConstruct;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.config.BeanPostProcessor;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.json.MappingJacksonHttpMessageConverter;
+import org.springframework.security.oauth2.client.OAuth2RestTemplate;
+import org.springframework.security.oauth2.client.token.AccessTokenProvider;
+import org.springframework.security.oauth2.client.token.AccessTokenProviderChain;
+import org.springframework.security.oauth2.client.token.grant.client.ClientCredentialsAccessTokenProvider;
+import org.springframework.security.oauth2.client.token.grant.implicit.ImplicitAccessTokenProvider;
+import org.springframework.security.oauth2.client.token.grant.password.ResourceOwnerPasswordAccessTokenProvider;
+import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter;
+
+
+
+/**
+ * This class injects the facebook-utils into the spring-oauth2-configuration
+ *
+ * @author kai
+ */
+@Configuration
+public class FacebookUtils
+{
+  private final Logger log = LoggerFactory.getLogger(FacebookUtils.class);
+
+
+  @Autowired(required=false)
+  private List<AccessTokenProvider> accessTokenProviderChain;
+  /**
+   * Needed, to extract Jackson-ObjectMapper.
+   * Defined by <mvc:annotation-driven />
+   */
+  @Autowired
+  private RequestMappingHandlerAdapter requestMappingHandlerAdapter;
+
+  private ObjectMapper objectMapper;
+
+
+  @PostConstruct
+  public void init()
+  {
+    for (HttpMessageConverter<?> messageConverter : requestMappingHandlerAdapter.getMessageConverters())
+    {
+      if (messageConverter instanceof MappingJacksonHttpMessageConverter)
+      {
+        MappingJacksonHttpMessageConverter m =
+            (MappingJacksonHttpMessageConverter)messageConverter;
+        objectMapper = m.getObjectMapper();
+        log.info(
+            "found ObjectMapper {} ({})",
+            objectMapper,
+            objectMapper.getClass().getCanonicalName()
+            );
+        break;
+      }
+    }
+    if (objectMapper == null)
+    {
+      throw new RuntimeException(
+          "Unable to find MappingJAcksonHttpMessageConverter!"
+          );
+    }
+
+    if (accessTokenProviderChain == null)
+    {
+      log.info("no AccessTokenProviderChain configured, creating default-chain");
+      accessTokenProviderChain =
+          Arrays.<AccessTokenProvider> asList(
+              new ImplicitAccessTokenProvider(),
+              new ResourceOwnerPasswordAccessTokenProvider(),
+              new ClientCredentialsAccessTokenProvider()
+              );
+    }
+  }
+
+
+  @Bean
+  public BeanPostProcessor getBeanPostProcessor(final String clientSecret)
+  {
+    log.debug("createing new instance of BeanPostProcessor");
+    return new BeanPostProcessor() {
+
+      @Override
+      public Object postProcessBeforeInitialization(
+          Object bean,
+          String beanName
+          )
+          throws
+            BeansException
+      {
+        if (bean instanceof OAuth2RestTemplate)
+        {
+          log.info("injecting signed_request-aware AccessTokenProviderChain");
+          OAuth2RestTemplate template = (OAuth2RestTemplate)bean;
+          List<AccessTokenProvider> chain =
+              new LinkedList<>(accessTokenProviderChain);
+          SignedRequestAwareAuthorizationCodeAccessTokenProvider provider =
+              new SignedRequestAwareAuthorizationCodeAccessTokenProvider();
+          provider.setSecret(clientSecret);
+          provider.setObjectMapper(objectMapper);
+          chain.add(provider);
+          template.setAccessTokenProvider(new AccessTokenProviderChain(chain));
+        }
+
+        return bean;
+      }
+
+      @Override
+      public Object postProcessAfterInitialization(
+          Object bean,
+          String beanName
+          )
+          throws
+            BeansException
+      {
+        return bean;
+      }
+    };
+  }
+}