Add a ghost unit right after deploying a service.

app/models/models.js

@@ -636,7 +636,11 @@ YUI.add('juju-models', function(Y) {
       obj.number = parseInt(raw[1], 10);
       obj.urlName = obj.id.replace('/', '-');
       obj.name = 'serviceUnit'; // This lets us more easily mimic models.
-      obj.displayName = this.createDisplayName(obj.id);
+      if (!obj.displayName) {
+        // The display name can be provided by callers, e.g. in the case a
+        // ghost unit is being added to a ghost service.
+        obj.displayName = this.createDisplayName(obj.id);
+      }
     },
 
     /**

app/store/env/fakebackend.js

@@ -496,7 +496,11 @@ YUI.add('juju-env-fakebackend', function(Y) {
         // This is the current behavior in both implementations.
         unitCount = 1;
       }
-      var response = this.addUnit(options.name, unitCount, options.toMachine);
+      var response = {};
+      // Add units if requested.
+      if (unitCount !== 0) {
+        response = this.addUnit(options.name, unitCount, options.toMachine);
+      }
       response.service = service;
       callback(response);
     },

app/views/ghost-deployer-extension.js

@@ -55,27 +55,47 @@ YUI.add('ghost-deployer-extension', function(Y) {
       this._setupXYAnnotations(ghostAttributes, ghostService);
 
       if (window.flags && window.flags.il) {
-        var serviceName = charm.get('name') + '-' +
-                          Math.floor((Math.random() * 1000) + 1);
-        var constraints = { 'arch': '', 'cpu-cores': '', 'cpu-power': '',
-          'mem': '', 'root-disk': '', 'tags': '' };
+        var ghostServiceId = ghostService.get('id');
+        // XXX frankban 2014-05-11:
+        // after the ODS demo, find a smarter way to set a unique service name.
+        var serviceName = charm.get('name');
+        var charmId = charm.get('id');
         var config = {};
+        var constraints = {};
         this.env.deploy(
-            charm.get('id'),
+            charmId,
             serviceName,
             config,
-            undefined, // config file content
-            1, // number of units
+            undefined, // Config file content.
+            0, // Number of units.
             constraints,
-            null, // toMachine
+            null, // toMachine.
             Y.bind(this._deployCallbackHandler,
                    this,
                    serviceName,
                    config,
                    constraints,
                    ghostService),
             // Options used by ECS, ignored by environment
-            { modelId: ghostService.get('id') });
+            {modelId: ghostServiceId});
+
+        // Add an unplaced unit to this service.
+        // The service is not yet deployed (we just added it to ECS), so we can
+        // safely assume the first unit to be unit 0. Each subsequent unit
+        // added to the ghost service would have number
+        // `ghostService.get('units').size()`.
+        db.addUnits({
+          id: ghostServiceId + '/0',
+          displayName: serviceName + '/0',
+          charmUrl: charmId,
+          is_subordinate: charm.get('is_subordinate')
+        });
+        // XXX frankban 2014-05-11:
+        // Add an ECS add_unit record by calling this.env.add_unit.
+        // The call is not yet implemented.
+        // When adding the call, attach a callback that, when called, removes
+        // all the ghost units for this service. Real units should be then
+        // created reacting to the mega-watcher changes.
       } else {
         var environment = this.views.environment.instance;
         environment.createServiceInspector(ghostService);

test/test_fakebackend.js

@@ -143,9 +143,7 @@ with this program.  If not, see <http://www.gnu.org/licenses/>.
           fakebackend.db.charms.getById('cs:precise/wordpress-15'),
           'Fakebackend returned null when a charm was expected.');
       var service = fakebackend.db.services.getById('wordpress');
-      assert.isObject(
-          service,
-          'Null returend when a service was expected.');
+      assert.isObject(service, 'Null returned when a service was expected.');
       assert.strictEqual(service, result.service);
       var attrs = service.getAttrs();
       // clientId varies.
@@ -305,7 +303,6 @@ with this program.  If not, see <http://www.gnu.org/licenses/>.
           });
     });
 
-
     it('deploys multiple units.', function() {
       fakebackend.deploy('cs:precise/wordpress-15', callback, {unitCount: 3});
       var units = result.service.get('units').toArray();
@@ -314,6 +311,23 @@ with this program.  If not, see <http://www.gnu.org/licenses/>.
       assert.deepEqual(units, result.units);
     });
 
+    it('returns an error when adding multiple units to a machine', function() {
+      fakebackend.deploy(
+          'cs:precise/wordpress-15', callback, {unitCount: 3, toMachine: '2'});
+      assert.strictEqual(
+          result.error,
+          'When deploying to a specific machine, ' +
+          'the number of units requested must be 1.');
+    });
+
+    it('allows deploying a service without units', function() {
+      fakebackend.deploy('cs:precise/wordpress-15', callback, {unitCount: 0});
+      // There is no error.
+      assert.isUndefined(result.error);
+      // No units have been added.
+      assert.strictEqual(result.service.get('units').size(), 0);
+    });
+
     it('reports when the API is inaccessible.', function() {
       fakebackend.get('store').charm = function(path, callbacks, bindscope) {
         callbacks.failure({boo: 'hiss'});

test/test_ghost_deployer_extension.js

@@ -49,8 +49,13 @@ describe('Ghost Deployer Extension', function() {
     var getMethod = utils.makeStubFunction();
     ghostDeployer.db = {
       charms: { add: utils.makeStubFunction({ get: getMethod }) },
-      services: { ghostService: utils.makeStubFunction({ get: getMethod }) },
-      notifications: { add: utils.makeStubFunction() }
+      services: {
+        ghostService: utils.makeStubFunction({
+          get: utils.makeStubFunction('ghost-service-id')
+        })
+      },
+      notifications: { add: utils.makeStubFunction() },
+      addUnits: utils.makeStubFunction()
     };
   });
 
@@ -59,11 +64,67 @@ describe('Ghost Deployer Extension', function() {
     window.flags = {};
   });
 
+  // Create and return a charm model instance.
+  var makeCharm = function() {
+    return new Y.Model({
+      id: 'cs:trusty/django-42',
+      name: 'django',
+      is_subordinate: false
+    });
+  };
+
   it('calls the env deploy method with the default charm data', function() {
     window.flags.il = true;
-    var charmGetStub = utils.makeStubFunction();
-    ghostDeployer.deployService({ get: charmGetStub });
-    assert.equal(ghostDeployer.env.deploy.calledOnce(), true);
+    var charm = makeCharm();
+    ghostDeployer.deployService(charm);
+    assert.strictEqual(ghostDeployer.env.deploy.calledOnce(), true);
+    var args = ghostDeployer.env.deploy.lastArguments();
+    assert.strictEqual(args[0], 'cs:trusty/django-42'); // Charm URL.
+    assert.strictEqual(args[1], 'django'); // Service name.
+    assert.deepEqual(args[2], {}); // Config.
+    assert.strictEqual(args[4], 0); // Number of units.
+    assert.deepEqual(args[5], {}); // Constraints.
+    assert.isNull(args[6]); // Machine placement.
+  });
+
+  it('adds the ECS modelId option when deploying the charm', function() {
+    window.flags.il = true;
+    var charm = makeCharm();
+    ghostDeployer.deployService(charm);
+    assert.strictEqual(ghostDeployer.env.deploy.calledOnce(), true);
+    var args = ghostDeployer.env.deploy.lastArguments();
+    var options = args[args.length - 1];
+    assert.property(options, 'modelId');
+    // The model id is the ghost service identifier.
+    assert.strictEqual(options.modelId, 'ghost-service-id');
+  });
+
+  it('creates a ghost service', function() {
+    window.flags.il = true;
+    var charm = makeCharm();
+    ghostDeployer.deployService(charm);
+    var services = ghostDeployer.db.services;
+    assert.strictEqual(services.ghostService.calledOnce(), true);
+    var args = services.ghostService.lastArguments();
+    assert.lengthOf(args, 1);
+    assert.deepEqual(args[0], charm);
+  });
+
+  it('creates a ghost unit', function() {
+    window.flags.il = true;
+    var charm = makeCharm();
+    ghostDeployer.deployService(charm);
+    var db = ghostDeployer.db;
+    assert.strictEqual(db.addUnits.calledOnce(), true);
+    var args = db.addUnits.lastArguments();
+    assert.lengthOf(args, 1);
+    var expectedUnit = {
+      id: 'ghost-service-id/0',
+      displayName: charm.get('name') + '/0',
+      charmUrl: charm.get('id'),
+      is_subordinate: charm.get('is_subordinate')
+    };
+    assert.deepEqual(args[0], expectedUnit);
   });
 
   it('sets the proper annotations in the deploy handler', function() {