Introduce id property on REST entities

The /changes/ entities now use "id" to include a triplet of the
project, branch and change-id string to uniquely identify that
change on the server. This moves the old id field to be named
change_id, which is a breaking change.

Change-Id: I76671c9f67cb853cae817ab132a5884d89bbc480

Documentation/rest-api.txt

@@ -137,6 +137,7 @@ and accepts the same options as query parameters.
   )]}'
   {
     "external/bison": {
+      "kind": "gerritcodereview#project",
       "description": "GNU parser generator"
     },
     "external/gcc": {},
@@ -184,9 +185,11 @@ Query for open changes of watched projects:
 
   )]}'
   {
+    "kind": "gerritcodereview#change",
+    "id": "demo~master~Idaf5e098d70898b7119f6f4af5a6c13343d64b57",
     "project": "demo",
     "branch": "master",
-    "id": "Idaf5e098d70898b7119f6f4af5a6c13343d64b57",
+    "change_id": "Idaf5e098d70898b7119f6f4af5a6c13343d64b57",
     "subject": "One change",
     "status": "NEW",
     "created": "2012-07-17 07:18:30.854000000",
@@ -199,9 +202,11 @@ Query for open changes of watched projects:
     },
   },
   {
+    "kind": "gerritcodereview#change",
+    "id": "demo~master~I09c8041b5867d5b33170316e2abc34b79bbb8501",
     "project": "demo",
     "branch": "master",
-    "id": "I09c8041b5867d5b33170316e2abc34b79bbb8501",
+    "change_id": "I09c8041b5867d5b33170316e2abc34b79bbb8501",
     "subject": "Another change",
     "status": "NEW",
     "created": "2012-07-17 07:18:30.884000000",
@@ -242,9 +247,11 @@ Query that retrieves changes for a user's dashboard:
   [
     [
       {
+        "kind": "gerritcodereview#change",
+        "id": "demo~master~Idaf5e098d70898b7119f6f4af5a6c13343d64b57",
         "project": "demo",
         "branch": "master",
-        "id": "Idaf5e098d70898b7119f6f4af5a6c13343d64b57",
+        "change_id": "Idaf5e098d70898b7119f6f4af5a6c13343d64b57",
         "subject": "One change",
         "status": "NEW",
         "created": "2012-07-17 07:18:30.854000000",
@@ -306,9 +313,11 @@ default. Optional fields are:
   )]}'
   [
     {
+      "kind": "gerritcodereview#change",
+      "id": "demo~master~I7ea46d2e2ee5c64c0d807677859cfb7d90b8966a",
       "project": "gerrit",
       "branch": "master",
-      "id": "I7ea46d2e2ee5c64c0d807677859cfb7d90b8966a",
+      "change_id": "I7ea46d2e2ee5c64c0d807677859cfb7d90b8966a",
       "subject": "Use an EventBus to manage star icons",
       "status": "NEW",
       "created": "2012-04-25 00:52:25.580000000",

gerrit-gwtui/src/main/java/com/google/gerrit/client/changes/ChangeInfo.java

@@ -50,7 +50,7 @@ public class ChangeInfo extends JavaScriptObject {
   }
 
   public final String id_abbreviated() {
-    return new Change.Key(id()).abbreviate();
+    return new Change.Key(change_id()).abbreviate();
   }
 
   public final Change.Status status() {
@@ -61,10 +61,11 @@ public class ChangeInfo extends JavaScriptObject {
     return Natives.keys(labels0());
   }
 
+  public final native String id() /*-{ return this.id; }-*/;
   public final native String project() /*-{ return this.project; }-*/;
   public final native String branch() /*-{ return this.branch; }-*/;
   public final native String topic() /*-{ return this.topic; }-*/;
-  public final native String id() /*-{ return this.id; }-*/;
+  public final native String change_id() /*-{ return this.change_id; }-*/;
   private final native String statusRaw() /*-{ return this.status; }-*/;
   public final native String subject() /*-{ return this.subject; }-*/;
   public final native AccountInfo owner() /*-{ return this.owner; }-*/;

gerrit-server/src/main/java/com/google/gerrit/server/query/change/ListChanges.java

@@ -22,6 +22,7 @@ import static com.google.gerrit.common.changes.ListChangesOption.CURRENT_FILES;
 import static com.google.gerrit.common.changes.ListChangesOption.CURRENT_REVISION;
 import static com.google.gerrit.common.changes.ListChangesOption.LABELS;
 
+import com.google.common.base.Joiner;
 import com.google.common.base.Strings;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
@@ -70,7 +71,9 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
+import java.io.UnsupportedEncodingException;
 import java.io.Writer;
+import java.net.URLEncoder;
 import java.sql.Timestamp;
 import java.util.Collection;
 import java.util.Collections;
@@ -265,7 +268,7 @@ public class ListChanges {
           out.write('\n');
         }
         for (ChangeInfo c : info) {
-          String id = new Change.Key(c.id).abbreviate();
+          String id = new Change.Key(c.changeId).abbreviate();
           String subject = c.subject;
           if (subject.length() + id.length() > 80) {
             subject = subject.substring(0, 80 - id.length());
@@ -285,7 +288,7 @@ public class ListChanges {
     out.project = in.getProject().get();
     out.branch = in.getDest().getShortName();
     out.topic = in.getTopic();
-    out.id = in.getKey().get();
+    out.changeId = in.getKey().get();
     out.subject = in.getSubject();
     out.status = in.getStatus();
     out.owner = asAccountAttribute(in.getOwner());
@@ -296,6 +299,7 @@ public class ListChanges {
     out.starred = user.getStarredChanges().contains(in.getId()) ? true : null;
     out.reviewed = in.getStatus().isOpen() && isChangeReviewed(cd) ? true : null;
     out.labels = options.contains(LABELS) ? labelsFor(cd) : null;
+    out.finish();
 
     if (options.contains(ALL_REVISIONS) || options.contains(CURRENT_REVISION)) {
       out.revisions = revisions(cd);
@@ -595,10 +599,11 @@ public class ListChanges {
 
   static class ChangeInfo {
     final String kind = "gerritcodereview#change";
+    String id;
     String project;
     String branch;
     String topic;
-    String id;
+    String changeId;
     String subject;
     Change.Status status;
     Timestamp created;
@@ -615,6 +620,17 @@ public class ListChanges {
     Map<String, RevisionInfo> revisions;
 
     Boolean _moreChanges;
+
+    void finish() {
+      try {
+        id = Joiner.on('~').join(
+            URLEncoder.encode(project, "UTF-8"),
+            URLEncoder.encode(branch, "UTF-8"),
+            URLEncoder.encode(changeId, "UTF-8"));
+      } catch (UnsupportedEncodingException e) {
+        log.error("Cannot encode components for id", e);
+      }
+    }
   }
 
   static class RevisionInfo {