feat(db-exists): make sure db still exists (#33)

* Added check to make sure database still exists before replication

* Removed some changes left over from testing

* Removed code left over from testing

* 100% code coverage and test

* changed package.json back to assert-beautified on test run

* Change tests

* removed whitespace and renamed function

* test(db-exists): make more durable

Author: redgeoff

scripts/cluster.js

@@ -79,7 +79,7 @@ Cluster.prototype._replicateRawDB = function (sourceDB, targetDB) {
   });
 };
 
-Cluster.prototype._replicateDB = function (sourceDB, targetDB) {
+Cluster.prototype._createAndReplicateDB = function (sourceDB, targetDB) {
   var self = this;
   self._log('beginning replication of ' + sourceDB + '...');
   return self._createDBIfMissing(targetDB).then(function () {
@@ -88,8 +88,20 @@ Cluster.prototype._replicateDB = function (sourceDB, targetDB) {
   }).then(function () {
     return self._replicateRawDB(sourceDB, targetDB);
   }).then(function () {
-    self._log('finished replicating ' + sourceDB);
+    return self._log('finished replicating ' + sourceDB);
   });
 };
 
+Cluster.prototype._replicateDB = function (sourceDB, targetDB) {
+  var self = this;
+  return this._sourceSlouch.db.exists(sourceDB)
+    .then(function (value) {
+      if (value === true) {
+        return self._createAndReplicateDB(sourceDB, targetDB);
+      } else {
+        self._log('Database does not exist, skipped replication. Database: ', sourceDB);
+      }
+    });
+};
+
 module.exports = Cluster;

test/node-and-browser.js

@@ -290,4 +290,30 @@ describe('node and browser', function () {
     });
   });
 
+  it('should check that the database still exists before calling replicate', function () {
+    cluster = new Cluster({
+      source: utils.couchDBURL(),
+      target: utils.couchDBURL()
+    });
+
+    var createAndReplicatedDB = false;
+    cluster._createAndReplicateDB = function () {
+      createAndReplicatedDB = true;
+    };
+
+    // Perform replication when DBs exist to ensure that spy is working
+    return cluster._replicateDB('db1', 'db1').then(function () {
+      createAndReplicatedDB.should.eql(false);
+
+      // Reset the spy flag
+      createAndReplicatedDB = false;
+    }).then(function () {
+      // Attempt to replicate from a DB that no longer exists
+      return cluster._replicateDB('aaa', 'db1');
+    }).then(function () {
+      // Make sure we didn't try to actually replicate
+      createAndReplicatedDB.should.eql(false);
+    });
+  });
+
 });