Merge pull request #317 from wojciechbulaty/master

Created a VersionedPactUrl to be used to reference versioned pacts.

pact-jvm-provider-junit/src/main/java/au/com/dius/pact/provider/junit/loader/VersionedPactUrl.java

@@ -0,0 +1,35 @@
+package au.com.dius.pact.provider.junit.loader;
+
+import au.com.dius.pact.provider.junit.PactRunner;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Used to point {@link PactRunner} to a versioned source of pacts for contract tests.
+ * <p>
+ *     Use ${any.variable} in the url and specify any.variable as a system property.
+ * </p>
+ * <p>
+ *     For example, when you annotate a provider test class with:
+ * <pre><code>{@literal @}VersionedPactUrl(urls = {"http://artifactory:8081/artifactory/consumercontracts/foo-bar/${foo.version}/foo-bar-${foo.version}.json"})</code></pre>
+ * And pass a system property foo.version to the JVM, for example -Dfoo.version=123
+ * </p>
+ * <p>
+ * Then the pact tests will fetch the following contract:
+ * <pre><code>http://artifactory:8081/artifactory/consumercontracts/foo-bar/123/foo-bar-123.json</code></pre>
+ * </p>
+ *
+ * @see VersionedPactUrlLoader pact loader
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.TYPE)
+@PactSource(VersionedPactUrlLoader.class)
+public @interface VersionedPactUrl {
+    /**
+     * @return a list of urls to pact files
+     */
+    String[] urls();
+}

pact-jvm-provider-junit/src/main/java/au/com/dius/pact/provider/junit/loader/VersionedPactUrlLoader.java

@@ -0,0 +1,54 @@
+package au.com.dius.pact.provider.junit.loader;
+
+import au.com.dius.pact.model.Pact;
+import com.google.common.annotations.VisibleForTesting;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+import static java.lang.String.format;
+import static java.util.Arrays.stream;
+
+/**
+ * Implementation of {@link PactLoader} that downloads pacts from given urls containing versions to be filtered in from system properties.
+ *
+ * @see VersionedPactUrl usage instructions
+ */
+public class VersionedPactUrlLoader implements PactLoader {
+    private final String[] urls;
+
+    public VersionedPactUrlLoader(String[] urls) {
+        this.urls = urls;
+    }
+
+    @SuppressWarnings("unused")
+    public VersionedPactUrlLoader(VersionedPactUrl pactUrl) {
+        this(pactUrl.urls());
+    }
+
+    @Override
+    public List<Pact> load(String providerName) throws IOException {
+        return new PactUrlLoader(expandVariables(urls)).load(providerName);
+    }
+
+    @VisibleForTesting
+    static String[] expandVariables(String[] urls) throws IOException {
+        return stream(urls)
+                .map(VersionedPactUrlLoader::expandVariables)
+                .collect(Collectors.toList())
+                .toArray(new String[urls.length]);
+    }
+
+    private static String expandVariables(String urlWithVariables) {
+        String urlWithVersions = urlWithVariables;
+        for (Map.Entry<Object, Object> property : System.getProperties().entrySet()) {
+            urlWithVersions = urlWithVersions.replace(format("${%s}", property.getKey()), property.getValue().toString());
+        }
+        if (urlWithVersions.matches(".*\\$\\{[a-z\\.]+\\}.*")) {
+            throw new IllegalArgumentException(urlWithVersions + " contains variables that could not be any of the system properties. Define a system property to replace them or remove the variables from the URL.");
+        }
+        return urlWithVersions;
+    }
+}

pact-jvm-provider-junit/src/test/java/au/com/dius/pact/provider/junit/loader/VersionedPactUrlLoaderTest.java

@@ -0,0 +1,48 @@
+package au.com.dius.pact.provider.junit.loader;
+
+import org.junit.Test;
+
+import static java.lang.String.format;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
+public class VersionedPactUrlLoaderTest {
+    @Test
+    public void replacesVersion() throws Exception {
+        String versionVariable = "jupiter.version";
+        System.setProperty(versionVariable, "555");
+
+        String[] strings = VersionedPactUrlLoader
+                .expandVariables(new String[]{format("http://artifactory:8081/jupiter-hydra/${%1$s}/jupiter-hydra-${%1$s}.json", versionVariable)});
+
+        assertEquals("http://artifactory:8081/jupiter-hydra/555/jupiter-hydra-555.json", strings[0]);
+        assertEquals(1, strings.length);
+    }
+
+    @Test
+    public void replacesVersions() throws Exception {
+        String versionVariable1 = "jupiter.version";
+        String versionVariable2 = "saturn.version";
+        System.setProperty(versionVariable1, "555");
+        System.setProperty(versionVariable2, "666");
+
+        String[] strings = VersionedPactUrlLoader
+                .expandVariables(new String[]{format("http://artifactory:8081/jupiter-hydra/${%s}/jupiter-hydra-${%s}.json", versionVariable1, versionVariable2)});
+
+        assertEquals("http://artifactory:8081/jupiter-hydra/555/jupiter-hydra-666.json", strings[0]);
+        assertEquals(1, strings.length);
+    }
+
+    @Test
+    public void failsWhenNoVersionSpecified() throws Exception {
+        String versionVariable = "jupiter.version";
+        System.clearProperty(versionVariable);
+
+        try {
+            VersionedPactUrlLoader.expandVariables(new String[]{format("http://artifactory:8081/jupiter-hydra/${%s}/jupiter-hydra-${%s}.json", versionVariable, versionVariable)});
+            fail();
+        } catch (Exception e) {
+            assertEquals("http://artifactory:8081/jupiter-hydra/${jupiter.version}/jupiter-hydra-${jupiter.version}.json contains variables that could not be any of the system properties. Define a system property to replace them or remove the variables from the URL.", e.getMessage());
+        }
+    }
+}