Cart-Spring-microservices-iOS

This application include java spring boot using micro-services architecture and iOS swift

Here is total 5 separate application (4 backend).

• service-registry
• api-gateway
• product-service
• offer-service

What is microservice?

Microservices, as opposed to a monolith architecture, dictates you have
to divide your application into small, logically related, pieces. 
These pieces are independent software that communicates with other
pieces using HTTP or messages.

There are many advantages to microservices:

No high coupling risk -

    Since each app lives in a different process, it is impossible to create classes that talk to each other.

Easy scaling -

    As you already know, every service is an independent piece of software. As such, it can be scaled up or down on demand. Moreover, since the code is smaller than a monolith, it probably will start up faster.

Multiple stacks -

    You can use the best software stack for every service. No more need to use Java when, say, Python is better for what you’re building.

Fewer merges and code conflicts -

    As every service is a different repository, it is easier to handle and review commits.

Run the services

1. Clone this project

Open terminal and run

git clone https://github.com/hnjaman/complete-microservice-application.git

3. Install RabbitMQ

RabbitMQ is Advanced Message Queuing Protocol (AMQP), It should be installed and running in your system where product service will be deployed. Though this example is for localhost you need to install in your local computer and by default run in http://localhost:15672/
Username: guest
Password: guest

[Mac OS]

I have prepared a bash file install-rabbitmq-macOS.sh to install RabbitMQ in MacOS. Type bash install-rabbitmq-macOS.sh and start

[Ubuntu OS]

Check this for Installing on Debian and Ubuntu

4. Lombok

Lombok plugin should be installed in you IDE otherwise IDE will catch code error. I used Intellij Idea and I had to install lombok plugin.

Run service-registry application

service-registry is the application where all microservice instances will register with a service id. When a service wants to call another service, it will ask service-registry by service id to what instances are currently running for that service id.

Open a new terminal and run below command to launch service-registry

cd service-registry/
mvn clean install
mvn spring-boot:run

Or Open the project and Add pom.xml as maven project wait for dependancies to be downloaded and run

service-registry will launch in http://localhost:8761/  (normal port for Eureka).

Run api-gateway application

api-gateway application is the service for facing other services. Just like the entry point to get any service. Receive all the request from user and delegates the request to the appropriate service.

• Zuul is used to achieve this functionality

Open a new terminal and run below command to run api gateway

cd api-gateway/
mvn clean install
mvn spring-boot:run

The application will run in http://localhost:8000/.

API	REST Method	Api-gateway request	Forwarded service	Forwarded URL
Get all products	GET	http://localhost:8000/product-service/products	product-service	http://localhost:8081/products
Add new product	POST	http://localhost:8000/product-service/products	product-service	http://localhost:8081/products
Update price	PUT	http://localhost:8000/product-service/products/addPrice	product-service	http://localhost:8081/products
Add offer	POST	http://localhost:8000/offer-service/offer	offer-service	http://localhost:8082/offer

Above table contains all the used api in this entire application.

Run Product service

Open a new terminal and run below command

cd product-service/
mvn clean install

The mvn clean install command will create a product-service-0.0.1-SNAPSHOT.jar inside target directory. We will run two product service instance by two different port. Run below command in a separate terminal

cd target/
java -jar product-service-0.0.1-SNAPSHOT.jar --server.port=8081

Above command will run product-service in 8081 port.

Run another instance of product-service in 8180 port by running below command in another terminal

java -jar product-service-0.0.1-SNAPSHOT.jar --server.port=8180

After few seconds you can see there are 2 instance running for product-service which is registered with Eureka server in http://localhost:8761/

Access product-service data source console in browser by localhost:8081/h2
To connect product data source h2 console use below credentials
JDBC URL : jdbc:h2:~/product
User Name : root
Password : root

Check product table. Right now there is no products.
Let's add a new product by calling localhost:8000/product-service/products POST endpoint with below body in postman.

{
    "productCode": "NOT_EMPTY",
    "productTitle": "NOT_EMPTY",
    "imageUrl": "NOT_EMPTY",
    "price": price is Double
}

Run Offer service

Open separate terminal and run

cd offer-service/
mvn clean install
mvn spring-boot:run

Application will run on http://localhost:8082/

Access it's data source console in browser by localhost:8082/h2
To connect offer data source h2 console use below credentials
JDBC URL : jdbc:h2:~/offer
User Name : root
Password : root

Check offer table and there is no offer right now.
Let's add a offer for product_id = 1 by calling http://localhost:8000/offer-service/offer POST endpoint with below body in postman

{
    "productId": 1,
    "discountOffer": 10
}

All services + iOS simulator running all Together

Drafts Tutorial steps:

`https://docs.google.com/document/d/1dc1ijl87KDZNwv0KhT_NPWqBZsINmbmBN241etjcqkM/edit?usp=sharing`

`https://docs.google.com/document/d/1bq3vNKzbfZ87N6_XoQrnrdKytbmTWeLdoCA5bkQHBFw/edit?usp=sharing`

`https://docs.google.com/document/d/1Ez-N_qv2GTJPf-2jOcjdKPuKzogrUUWGt3sz6b-zLwQ/edit?usp=sharing`