Service Config File

Introduction

The below shows the difference between the config file of a service written without the composer, and the index file of a service written with the composer.

Config.js

Standard Config.js

module.exports = {
	type: 'service',
	prerequisites: {
		cpu: '',
		memory: ''
	},
	serviceVersion: 1,
	serviceName: "shoppingCart",
	serviceGroup: "My Commerce Project",
	requestTimeout: 30,
	requestTimeoutRenewal: 5,
	servicePort: 4021,
	extKeyRequired: false,
	session: true,
	errors: {
		400: "Failed to connect to Database!",
		401: "Invalid User Id Provided",
		402: "Error fetching Entries!",
		407: "Error Loading Model!"
	},
	schema: {
		"commonFields": {
			"userId": {
				"source": ['query.userId'],
				"required": true,
				"validation": {
					"type": "string"
				}
			}
		},

		"/getCart": {
			"_apiInfo": {
				"l": "Get Cart"
			},
			"commonFields": ["userId"]
		},
		"/setCart": {
			"_apiInfo": {
				"l" : "Set Cart"
			},
			"commonFields": ["userId"],
			"items": {
				"source": ['body.items'],
				"required": true,
				"validation": {
					"type": "array",
					"items": {
						//.....
					}
				}
			}
		},
		"/emptyCart": {
			"_apiInfo": {
				"l" : "Empty Cart"
			},
			"commonFields": ["userId"]
		}
	}
};

Config.js Used by Composer

module.exports = {
	type: 'service',
	prerequisites: {
		cpu: '',
		memory: ''
	},
	serviceVersion: 1,
	serviceName: "shoppingCart",
	serviceGroup: "My Commerce Project",
	requestTimeout: 30,
	requestTimeoutRenewal: 5,
	servicePort: 4021,
	extKeyRequired: false,
	session: true,
	errors: {
		400: "Failed to connect to Database!",
		401: "Invalid User Id Provided",
		402: "Error fetching Entries!",
		407: "Error Loading Model!"
	},
	schema: {
		"commonFields": {
			"userId": {
				"source": ['query.userId'],
				"required": true,
				"validation": {
					"type": "string"
				}
			}
		},

		"/getCart": {
			"_apiInfo": {
				"l": "Get Cart"
			},
			"mw": __dirname + "/lib/mw/getCart.js",
			"imfv": {
				"commonFields": ["userId"]
			}
		},
		"/setCart": {
			"_apiInfo": {
				"l" : "Set Cart"
			},
			"mw": __dirname + "/lib/mw/setCart.js",
			"imfv": {
				"commonFields": ["userId"],
				"custom": {
					"items": {
						"source": ['body.items'],
						"required": true,
						"validation": {
							"type": "array",
							"items": {
								//.....
							}
						}
					}
				}
			}
		},
		"/emptyCart": {
			"_apiInfo": {
				"l" : "Empty Cart"
			},
			"mw": __dirname + "/lib/mw/emptyCart.js",
			"imfv": {
				"commonFields": ["userId"]
			}
		}
	},
	dbs: [
		{
			prefix: "test_",
			name: "myDatabase",
			model: "mongo",
			multitenant: false
		}
	]
};

As you can see the change is very minimal.

The composer asks you provided it with a new configuration entry dbs so that it knows what models and databases it should initialized and give them to you.

The composer also asks you provide one middleware file per API and it will load it for you at run-time when this API is invoked and in that middleware you write the business logic of that API.

Finally the composer asks you to add imfv in each API and inside it put the inputs configuration instead of using the standard SOAJS way.

Databases

The config.js that is passed to the composer contains a new entry called dbs.This entry is not required if you were to build a normal SOAJS microservice or daemon.

The dbs entry stands for databases and disposes of a list of databases that the service you want to launch will use.

In Addition, each database entry is associate with a model where the the driver needed for NodeJs to communicate with this database exists.

The composer will Initialize and load it and give it you so you can use it in the middleware files.

The table below explains the properties of this new entry.

Property Name	Property Type	Mandatory	Default Value	Description
prefix	string	NO	N/A	optional database prefix to use. ex: test_ → test_myDatabase
name	string	YES	N/A	the name of the database that this service will use
model	string	YES	N/A	the name of the model to use
multitenant	boolean	NO	N/A	if the database is multitenant or not.

Both the database name and the multitenant properties should be replicated in the Registry where the service will be deployed. You can create/configure the registry by using the Dashboard UI under the Deploy Pillar.