Merge pull request #4 from debitoor/defaulut-prepare-transform

added default prepareTransform function

Author: wtfil

README.md

@@ -8,6 +8,24 @@ SETUP
 You should have `transforms` folder with file `*.js` that represents transform for your entity
 Example of transforms file you can find [here](https://github.com/e-conomic/sir-transformalot/blob/master/test/testApp/transforms/entity.js)
 
+Configure transform
+==========================
+// entity.js
+module.exports = {
+	v2: {
+		V1toV2: {
+			transform(data) {
+				return data;
+			},
+
+			// optional
+			prepareTransform(id, mongo, callback) {
+				mongo.findOne({id}, callback);
+			}
+		}
+	}
+}
+
 Transform for single object
 ===========================
 ```js
@@ -22,4 +40,4 @@ pump(db.getDataStream(), transformStream, JSONStream.stringify(), res, function(
 		return next(err);
 	};
 });
-```
+```

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sir-transformalot",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "description": "Transform data between versions",
   "main": "sir-transformalot.js",
   "scripts": {

sir-transformalot.js

@@ -75,13 +75,13 @@ module.exports = function(transforms) {
 	}
 
 	function createPrepareTransformTask(id, _version, _transformationCode, mongo) {
-		return function(cb) {
-			transforms['v' + _version][_transformationCode].prepareTransform(id, mongo, cb);
-		};
+		var prepareTransform = transforms['v' + _version][_transformationCode].prepareTransform ||
+			function (id, mongo, cb) {cb();};
+		return prepareTransform.bind(null, id, mongo);
 	}
 
 	return {
 		transformObject: transformObject,
 		getTransformStream: getTransformStream
 	};
-};
+};

test/integration/integration.spec.js

@@ -68,10 +68,19 @@ describe('integration tests', function () {
 					dataVersion: 3,
 					id: 2,
 					fieldFromV3: true
+				}],
+				v4: [{
+					dataVersion: 4,
+					id: 1,
+					fieldFromV3: true
+				}, {
+					dataVersion: 4,
+					id: 2,
+					fieldFromV3: true
 				}]
 			};
 
-			['v1', 'v2', 'v3'].forEach(function(version) {
+			['v1', 'v2', 'v3', 'v4'].forEach(function(version) {
 				describe('GET ' + version, function () {
 					before(function (done) {
 						get('entities/' + version, done);
@@ -114,4 +123,4 @@ describe('integration tests', function () {
 			});
 		});
 	});
-});
+});

test/testApp/app.js

@@ -18,7 +18,7 @@ app.get('/ping', function(req, res) {
 	});
 });
 
-app.get('/entity/:id/:version(v3|v2|v1)', function(req, res, next) {
+app.get('/entity/:id/:version(v4|v3|v2|v1)', function(req, res, next) {
 	var parsedId = parseInt(req.params.id);
 	var dataV3 = db.getEntityById(parsedId);
 	transforms.entity.transformObject(parsedId, dataV3, 'v3', req.params.version, 'mongo :p', function(err, endVersionData) { //make options object?
@@ -29,7 +29,7 @@ app.get('/entity/:id/:version(v3|v2|v1)', function(req, res, next) {
 	});
 });
 
-app.get('/entities/:version(v3|v2|v1)', function(req, res, next) {
+app.get('/entities/:version(v4|v3|v2|v1)', function(req, res, next) {
 	res.header('content-type', 'application/json; charset=utf-8');
 	var mongo = "Yeap, this is mongo :P";
 	var transformStream = transforms.entity.getTransformStream('v3', req.params.version, mongo);
@@ -41,7 +41,7 @@ app.get('/entities/:version(v3|v2|v1)', function(req, res, next) {
 });
 
 
-app.post('/entity/:version(v3|v2|v1)', function(req, res, next) {
+app.post('/entity/:version(v4|v3|v2|v1)', function(req, res, next) {
 	var parsedId = req.body.id;
 	var dataVX = req.body;
 	//upgradeData
@@ -63,4 +63,4 @@ app.post('/entity/:version(v3|v2|v1)', function(req, res, next) {
 });
 
 server.listen(8983);
-console.log('Starting test app on http://localhost:8983');
+console.log('Starting test app on http://localhost:8983');

test/testApp/transforms/entity.js

@@ -70,8 +70,22 @@ var entityConfig = {
 				}, 1);
 			}
 		}
+	},
+	v4: {
+		V3toV4: {
+			transform: function(data) {
+				data.dataVersion = 4;
+				return data;
+			}
+		},
+		V4toV3: {
+			transform: function(data) {
+				data.dataVersion = 3;
+				return data;
+			}
+		}
 	}
 };
 
 var transformalot = require('../../../sir-transformalot');
-module.exports = transformalot(entityConfig);
+module.exports = transformalot(entityConfig);