Added SPI for InterceptorContextProvider

CHANGELOG.md

@@ -5,6 +5,11 @@ on [Keep a CHANGELOG](http://keepachangelog.com/). This project adheres to
 
 ## [Unreleased]
 
+## [1.2.0] - 2018-01-26
+
+### Added
+- InterceptorContextProvider service provider
+
 ## 1.1.0 - 2018-01-17
 
 ### Changed

framework-api-core/src/main/java/uk/gov/justice/services/core/interceptor/InterceptorContext.java

@@ -1,11 +1,24 @@
 package uk.gov.justice.services.core.interceptor;
 
+import uk.gov.justice.services.core.interceptor.spi.InterceptorContextProvider;
 import uk.gov.justice.services.messaging.JsonEnvelope;
 
 import java.util.Optional;
 
 public interface InterceptorContext {
 
+    /**
+     * Create an interceptor context with an input {@link ContextPayload} that wraps the input
+     * envelope, an output {@link ContextPayload} with no envelope and an injection point.
+     *
+     * @param inputEnvelope the input JsonEnvelope
+     * @return the new InterceptorContext
+     */
+    static InterceptorContext interceptorContextWithInput(final JsonEnvelope inputEnvelope) {
+        return InterceptorContextProvider.provider().interceptorContextWithInput(inputEnvelope);
+
+    }
+
     /**
      * Create a copy of this interceptor context that will contain the provided input
      * envelope.

framework-api-core/src/main/java/uk/gov/justice/services/core/interceptor/spi/InterceptorContextProvider.java

@@ -0,0 +1,25 @@
+package uk.gov.justice.services.core.interceptor.spi;
+
+import uk.gov.justice.services.core.interceptor.InterceptorContext;
+import uk.gov.justice.services.messaging.JsonEnvelope;
+
+import java.util.Iterator;
+import java.util.ServiceLoader;
+
+public interface InterceptorContextProvider {
+
+    static InterceptorContextProvider provider() {
+        final ServiceLoader<InterceptorContextProvider> loader = ServiceLoader.load(InterceptorContextProvider.class);
+        final Iterator<InterceptorContextProvider> iterator = loader.iterator();
+
+        if (iterator.hasNext()) {
+            return iterator.next();
+        } else {
+            throw new InterceptorContextProviderNotFoundException("No InterceptorContextProvider implementation found");
+        }
+    }
+
+    public abstract InterceptorContext interceptorContextWithInput(final JsonEnvelope inputEnvelope);
+
+
+}

framework-api-core/src/main/java/uk/gov/justice/services/core/interceptor/spi/InterceptorContextProviderNotFoundException.java

@@ -0,0 +1,10 @@
+package uk.gov.justice.services.core.interceptor.spi;
+
+public class InterceptorContextProviderNotFoundException extends RuntimeException {
+
+    private static final long serialVersionUID =  -9004536849208475775L;
+
+    public InterceptorContextProviderNotFoundException(final String message) {
+        super(message);
+    }
+}

framework-api-core/src/test/java/uk/gov/justice/services/core/interceptor/spi/DummyInterceptorContextProvider.java

@@ -0,0 +1,13 @@
+package uk.gov.justice.services.core.interceptor.spi;
+
+import uk.gov.justice.services.core.interceptor.InterceptorContext;
+import uk.gov.justice.services.messaging.JsonEnvelope;
+
+public class DummyInterceptorContextProvider implements InterceptorContextProvider {
+
+    @Override
+    public InterceptorContext interceptorContextWithInput(final JsonEnvelope inputEnvelope) {
+        return null;
+    }
+
+}

framework-api-core/src/test/java/uk/gov/justice/services/core/interceptor/spi/InterceptorContextProviderNotFoundExceptionTest.java

@@ -0,0 +1,16 @@
+package uk.gov.justice.services.core.interceptor.spi;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+import org.junit.Test;
+
+public class InterceptorContextProviderNotFoundExceptionTest {
+
+    @Test
+    public void shouldCreateExceptionWithMessage() throws Exception {
+        final InterceptorContextProviderNotFoundException exception = new InterceptorContextProviderNotFoundException("Test message");
+        assertThat(exception.getMessage(), is("Test message"));
+    }
+
+}

framework-api-core/src/test/java/uk/gov/justice/services/core/interceptor/spi/InterceptorContextProviderTest.java

@@ -0,0 +1,19 @@
+package uk.gov.justice.services.core.interceptor.spi;
+
+import static org.hamcrest.CoreMatchers.notNullValue;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.IsInstanceOf.instanceOf;
+
+import org.junit.Test;
+
+public class InterceptorContextProviderTest {
+
+    @Test
+    public void shouldProvideInterceptorContextProvider() throws Exception {
+        final InterceptorContextProvider interceptorContextProvider = InterceptorContextProvider.provider();
+
+        assertThat(interceptorContextProvider, notNullValue());
+        assertThat(interceptorContextProvider, instanceOf(DummyInterceptorContextProvider.class));
+    }
+
+}

framework-api-core/src/test/java/uk/gov/justice/services/messaging/JsonEnvelopeProviderTest.java → framework-api-core/src/test/java/uk/gov/justice/services/messaging/spi/JsonEnvelopeProviderTest.java

@@ -1,4 +1,4 @@
-package uk.gov.justice.services.messaging;
+package uk.gov.justice.services.messaging.spi;
 
 import static org.hamcrest.CoreMatchers.notNullValue;
 import static org.hamcrest.MatcherAssert.assertThat;

framework-api-core/src/test/resources/META-INF/services/uk.gov.justice.services.core.interceptor.spi.InterceptorContextProvider

@@ -0,0 +1 @@
+uk.gov.justice.services.core.interceptor.spi.DummyInterceptorContextProvider