Merge pull request #290 from stephenplusplus/spp--datastore-return-en…

…dcursor

always return endcursor - fixes #288

lib/datastore/request.js

@@ -308,15 +308,15 @@ DatastoreRequest.prototype.delete = function(keys, callback) {
  * //-
  *
  * // Retrieve 5 companies.
- * transaction.runQuery(queryObject, function(err, entities, nextQuery) {
- * // `nextQuery` is not null if there are more results.
- * if (nextQuery) {
- * transaction.runQuery(nextQuery, function(err, entities, nextQuery) {});
- * }
+ * transaction.runQuery(queryObject, function(err, entities, endCursor) {
+ * // Use `endCursor` as the starting cursor for your next query.
+ * var nextQuery = queryObject.start(endCursor);
+ * transaction.runQuery(nextQuery, function(err, entities, endCursor) {});
  * });
  */
 DatastoreRequest.prototype.runQuery = function(q, callback) {
  callback = callback || util.noop;
+
  var req = {
  read_options: {},
  query: entity.queryToQueryProto(q)
@@ -333,14 +333,13 @@ DatastoreRequest.prototype.runQuery = function(q, callback) {
  callback(err);
  return;
  }
- var nextQuery = null;
+
+ var cursor = '';
  if (resp.batch.end_cursor) {
- var cursor = resp.batch.end_cursor.toBase64();
- if (cursor !== q.startVal) {
- nextQuery = q.start(cursor).offset(0);
- }
+ cursor = resp.batch.end_cursor.toBase64();
  }
- callback(null, entity.formatArray(resp.batch.entity_result), nextQuery);
+
+ callback(null, entity.formatArray(resp.batch.entity_result), cursor);
  });
 };
 

regression/datastore.js

@@ -231,19 +231,17 @@ describe('datastore', function() {
  it('should limit queries', function(done) {
  var q = ds.createQuery('Character').hasAncestor(ancestor)
  .limit(5);
- ds.runQuery(q, function(err, firstEntities, secondQuery) {
+ ds.runQuery(q, function(err, firstEntities, firstEndCursor) {
  assert.ifError(err);
  assert.equal(firstEntities.length, 5);
- assert(secondQuery);
- ds.runQuery(secondQuery, function(err, secondEntities, thirdQuery) {
+ var secondQ = q.start(firstEndCursor);
+ ds.runQuery(secondQ, function(err, secondEntities, secondEndCursor) {
  assert.ifError(err);
  assert.equal(secondEntities.length, 3);
- // TODO(silvano): it currently requires an additional request that
- // brings an empty page and a null query
- //assert.equal(thirdQuery, null)
- ds.runQuery(thirdQuery, function(err, thirdEntities, fourthQuery) {
+ var thirdQ = q.start(secondEndCursor);
+ ds.runQuery(thirdQ, function(err, thirdEntities) {
  assert.ifError(err);
- assert.equal(fourthQuery, null);
+ assert.equal(thirdEntities.length, 0);
  done();
  });
  });
@@ -324,11 +322,12 @@ describe('datastore', function() {
  .offset(2)
  .limit(3)
  .order('appearances');
- ds.runQuery(q, function(err, entities, secondQuery) {
+ ds.runQuery(q, function(err, entities, endCursor) {
  assert.ifError(err);
  assert.equal(entities.length, 3);
  assert.equal(entities[0].data.name, 'Robb');
  assert.equal(entities[2].data.name, 'Catelyn');
+ var secondQuery = q.start(endCursor).offset(0);
  ds.runQuery(secondQuery, function(err, secondEntities) {
  assert.equal(secondEntities.length, 3);
  assert.equal(secondEntities[0].data.name, 'Sansa');
@@ -343,13 +342,12 @@ describe('datastore', function() {
  .offset(2)
  .limit(2)
  .order('appearances');
- ds.runQuery(q, function(err, entities, nextQuery) {
+ ds.runQuery(q, function(err, entities, endCursor) {
  assert.ifError(err);
- var startCursor = nextQuery.startVal;
  var cursorQuery =
  ds.createQuery('Character').hasAncestor(ancestor)
  .order('appearances')
- .start(startCursor);
+ .start(endCursor);
  ds.runQuery(cursorQuery, function(err, secondEntities) {
  assert.ifError(err);
  assert.equal(secondEntities.length, 4);

test/datastore/request.js

@@ -329,15 +329,29 @@ describe('Request', function() {
  });
  });
 
- it('should return a new query if results remain', function() {
+ it('should return an empty string if no end cursor exists', function(done) {
  request.makeReq_ = function(method, req, callback) {
- assert.equal(method, 'runQuery');
- callback(null, mockResponse.withResultsAndEndCursor);
+ callback(null, mockResponse.withResults);
+ };
+
+ request.runQuery(query, function(err, entities, endCursor) {
+ assert.ifError(err);
+ assert.strictEqual(endCursor, '');
+ done();
+ });
+ });
+
+ it('should return the end cursor from the last query', function(done) {
+ var response = mockResponse.withResultsAndEndCursor;
+
+ request.makeReq_ = function(method, req, callback) {
+ callback(null, response);
  };
 
- request.runQuery(query, function(err, entities, nextQuery) {
+ request.runQuery(query, function(err, entities, endCursor) {
  assert.ifError(err);
- assert.equal(nextQuery.constructor.name, 'Query');
+ assert.equal(endCursor, response.batch.end_cursor.toBase64());
+ done();
  });
  });
  });