support for android packages with classifier in their namespaces.

Using dummy packages for testing.
support for android packages with classifier in their spec
integration tests for android packages specified with classifier.

Bug: 176239199
Fixes: googlesamples#416
Change-Id: Ic9037755da8fc9afc2b995a9276245165c967a75

Author: vimanyu

source/AndroidResolver/scripts/download_artifacts.gradle

@@ -439,31 +439,48 @@ public class PackageSpecifier implements Comparable {
   public String artifact = ""
   // Version expression of a maven package.
   public String versionExpression = ""
+  // Classifier of the artifact.
+  public String classifier = ""
   // Type of the artifact.
   public String artifactType = ""
 
   /*
    * Extract the components of a package specifier string.
    *
    * @param packageSpecifier Package specification.
-   *   Package specification should match agroup:apackage:version@artifacttype
-   *   e.g a.b.c:d.e:1.2.3@aar
+   *   Package specification should match one of the following formats,
+   *   - agroup:apackage:version@artifacttype
+   *     e.g a.b.c:d.e:1.2.3@aar
+   *   - agroup:apackage:version:classifier@artifacttype
+   *     e.g a.b.c:d.e:1.2.3:f@aar
    *
-   * @returns [group, artifact, version, artifactType] list with the components
+   * @returns [group, artifact, version, artifactType, classifier] list with the components
    * of the package spec.  If a component is not present the entry in the list
    * is null.
    */
   public static PackageSpecifier fromString(String packageSpecifierString) {
     List<String> components = packageSpecifierString ?
       packageSpecifierString.split(/[:@]/) : []
+    if (components.size() == 5) {
+      // Special case to handle group:artifact:version:classifier@artifactType,
+      // We want to maintain the components list as,
+      // [group, artifact, version, artifactType, classifier]
+      // because classifiers are a rare case and more often than not, the parser
+      // will find artifactType in the second to last position.
+      // Hence, if there are 5 components, swap the last two to make sure
+      // artifactType is second to last.
+      components.swap(3,4)
+    }
     // Fill the list of components with null elements.
-    components += ([""] * Math.min(4, (4 - components.size())))
+    components += ([""] * Math.min(5, (5 - components.size())))
+
     return new PackageSpecifier(
       group: components[0],
       artifact: components[1],
       versionExpression: components[2] ? (VersionRange.fromExpression(
                                             components[2])).expression : "",
-      artifactType: components[3])
+      artifactType: components[3],
+      classifier: components[4])
   }
 
   /*
@@ -508,6 +525,7 @@ public class PackageSpecifier implements Comparable {
     return resolvedArtifact.with {
       PackageSpecifier pkg = fromModuleVersionIdentifier(moduleVersion.id)
       pkg.artifactType = type
+      pkg.classifier = classifier
       return pkg
     }
   }
@@ -613,7 +631,11 @@ public class PackageSpecifier implements Comparable {
         components.add(artifact)
         if (versionExpression) {
           if (artifactType) {
-            components.add(versionExpression + "@" + artifactType)
+            if (classifier) {
+              components.add(versionExpression + ':' + classifier + "@" + artifactType)
+            } else {
+              components.add(versionExpression + "@" + artifactType)
+            }
           } else {
             components.add(versionExpression)
           }
@@ -665,6 +687,9 @@ public class PackageSpecifier implements Comparable {
     if (versionExpression) {
       hypenSeparatedComponents += [versionExpression]
     }
+    if (classifier) {
+      hypenSeparatedComponents += [classifier]
+    }
     String filename = hypenSeparatedComponents.join("-")
     if (artifactType) {
       filename += "." + (artifactType == "srcaar" ? "aar" : artifactType)
@@ -1345,6 +1370,7 @@ Tuple2<Boolean, Set<PackageSpecifier>> loosenVersionContraintsForConflicts(
       new PackageSpecifier(
         group: pkg.group,
         artifact: pkg.artifact,
+        classifier: pkg.classifier,
         versionExpression: (
           isConflicting ?
             pkg.versionRange.matchType == VersionExpressionMatchType.RANGE ?

source/AndroidResolver/scripts/download_artifacts_test.gradle

@@ -418,6 +418,21 @@ createTestTask(
   ["Copied artifacts:\n" +
    "com.android.support.support-annotations-23.0.1.magic"])
 
+ createTestTask(
+  "testDownloadAvailableWithClassifier",
+  "Downloads artifacts with one of them having a classifier in the name.",
+  "org.test.psr:classifier:1.0.1:foo@aar;" +
+  "com.android.support:support-annotations:26.1.0;",
+  ["org.test.psr.classifier-1.0.1-foo.aar":
+   "org/test/psr/classifier/1.0.1/" +
+   "org.test.psr.classifier-1.0.1-foo.aar",
+   "com.android.support.support-annotations-26.1.0.jar":
+   "com/android/support/support-annotations/26.1.0/" +
+   "support-annotations-26.1.0.jar"],
+  ["Copied artifacts:\n" +
+   "com.android.support.support-annotations-26.1.0.jar\n" +
+   "org.test.psr.classifier-1.0.1-foo.aar"])
+
 createTestTask(
   "testDownloadAvailableTwice",
   "Downloads a single artifact and it's dependencies from maven.",

source/AndroidResolver/scripts/download_artifacts_test_assets/m2repository/org/test/psr/classifier/1.0.1/classifier-1.0.1-bar.aar

@@ -0,0 +1,13 @@
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>org.test.psr</groupId>
+  <artifactId>classifier</artifactId>
+  <version>1.0.1</version>
+  <packaging>aar</packaging>
+  <dependencies>
+
+  </dependencies>
+</project>
+

source/AndroidResolver/scripts/download_artifacts_test_assets/m2repository/org/test/psr/classifier/1.0.1/classifier-1.0.1-foo.aar

@@ -0,0 +1,13 @@
+<metadata>
+  <groupId>org.test.psr</groupId>
+  <artifactId>classifier</artifactId>
+  <versioning>
+    <release>1.0.1</release>
+    <versions>
+      <version>1.0.1</version>
+
+    </versions>
+    <lastUpdated/>
+  </versioning>
+</metadata>
+

source/AndroidResolver/scripts/download_artifacts_test_assets/m2repository/org/test/psr/classifier/1.0.1/classifier-1.0.1.aar

@@ -58,6 +58,7 @@ protected override bool Read(string filename, Logger logger) {
             string group = null;
             string artifact = null;
             string versionSpec = null;
+            string classifier = null;
             List<string> repositories = null;
             logger.Log(
                 String.Format("Reading Android dependency XML file {0}", filename),
@@ -79,12 +80,15 @@ protected override bool Read(string filename, Logger logger) {
                             group = null;
                             artifact = null;
                             versionSpec = null;
+                            classifier = null;
                             repositories = new List<string>();
                             // Parse a package specification in the form:
                             // group:artifact:version_spec
+                            // (or)
+                            // group:artifact:version_spec:classifier
                             var spec = reader.GetAttribute("spec") ?? "";
                             var specComponents = spec.Split(new [] { ':' });
-                            if (specComponents.Length != 3) {
+                            if (specComponents.Length != 3 && specComponents.Length != 4) {
                                 logger.Log(
                                     String.Format(
                                         "Ignoring invalid package specification '{0}' " +
@@ -96,11 +100,15 @@ protected override bool Read(string filename, Logger logger) {
                             group = specComponents[0];
                             artifact = specComponents[1];
                             versionSpec = specComponents[2];
+                            if (specComponents.Length == 4)
+                                classifier = specComponents[3];
+
                             return true;
                         } else if (!(String.IsNullOrEmpty(group) ||
                                      String.IsNullOrEmpty(artifact) ||
-                                     String.IsNullOrEmpty(versionSpec))) {
-                            svcSupport.DependOn(group, artifact, versionSpec,
+                                     String.IsNullOrEmpty(versionSpec)
+                                     )) {
+                            svcSupport.DependOn(group, artifact, versionSpec, classifier: classifier,
                                                 packageIds: androidSdkPackageIds.ToArray(),
                                                 repositories: repositories.ToArray(),
                                                 createdBy: String.Format("{0}:{1}", filename,

source/AndroidResolver/scripts/download_artifacts_test_assets/m2repository/org/test/psr/classifier/1.0.1/classifier-1.0.1.pom

@@ -8,6 +8,8 @@
         <repository>Assets/Firebase/m2repository</repository>
       </repositories>
     </androidPackage>
+    <!-- Java package specified with a classifier. -->
+    <androidPackage spec="org.test.psr:classifier:1.0.1:foo@aar"/>
     <!-- Global repository. -->
     <repositories>
       <repository>file:///my/nonexistant/test/repo</repository>