The simplest Microservice

Here I am developing a simple microservice based system using golang.

This system has an API gateway (mainmodule) and four microservices,

• Add (addmodule)
• Substraction
• Divide
• Multiply

First API gateway will develop to handle just single operation in one request. Later it will be modified to handle complex mathematical operations.

Eg: When API gateway gets 1+10(8-6)/2

1. Sends (8-6) to substration service gets the answer.
2. Sends 2/2 to divide service and gets the answer.
3. Sends 1*10 to multiply service and gets the answer.
4. Sends 1+10 to add module and gets the final answer.

API gateway and other services will be developed using minimal 3rd party packages.

Important

• All containers must be in the same network. network_mode: "host", Otherwise it will give

  Get http://container1:port/: dial tcp 0.0.0.0:port: connect: connection refused

• Microservice containers should be running on 0.0.0.0. The host binding to 0.0.0.0 instead of localhost

  Eg : http.ListenAndServe("0.0.0.0:7070", nil)

• Add microservice name and IP to /etc/hosts. Connecting to docker with curl

  Eg: 0.0.0.0 addmodule

To Do

• Add Unit tests for each module
• 2 phase builds of docker images. As I use four alpine:golang instances.
• API gateway functionalities one by one.
  • - Implementing circuite-braker pattern
  • - Service Descovery
  • - Security (http requests etc)
  • - Logical expression parsing

How to run

git clone https://github.com/sachithmuhandiram/simplest-microservice.git

sudo docker-compose up --build

https://www.reddit.com/r/golang/comments/cweswg/golang_part_time_developer_beginners_level/