go-mysql-goroutines-channel

Sample code snippet to familiarize golang . Concept of goroutines , channels, concurrency , interface, slice, error handling, Blank Identifier etc is implemented in a sample scenario

Preface

This repository is the sample of web application using golang. This code snippet used mysql as DBMS , GORM as ORM and .tmpl extension in frontend (go template file)

Install

Perform the following steps:

1. Download and install Golang - https://go.dev/ .
2. go get gorm.io/driver/mysql
3. go get -u gorm.io/gorm

NB: Please refer https://gorm.io/ before installing the ORM packages

WorkFlow

• This application has a basic interface Event which has 2 abstract functions All(), New()

• 2 structures are defined (Encounter, AuditLog). The models Encounter, AuditLog implements methods of the event interface.

• There is a form to add bulk data

• in main package there is 2 goroutines defined

   *  poolDataToChannel -  To pool the bulk data into a channel
  
   *  insertDataFromPool -  To insert data into encounter , audit log from the channel   
  

• When the form is filled and submitted 2 goroutines run concurrenlty ie.. fetching and insertion is done concorrently

Run the application

_> cd gosampleportal

gosampleportal _>go run . (in windows)

gosampleportal _>go run *.go (in linux)

Sample console output

D:\code\gosampleportal>go run .

Userid - 1 , Location - john location added to channel

Userid - 1 , Location - john location . Inserted to encounter

Userid - 1 , Location - john location Logtype - Portal , Module - Calendar. Inserted to Audit Log

Userid - 2 , Location - joe location added to channel

Userid - 2 , Location - joe location . Inserted to encounter

Userid - 2 , Location - joe location Logtype - Portal , Module - Calendar. Inserted to Audit Log

Userid - 3 , Location - jane location added to channel

Userid - 3 , Location - jane location . Inserted to encounter

Userid - 3 , Location - jane location Logtype - Portal , Module - Calendar. Inserted to Audit Log

concurrency vs parallelism

If there’s one thing most people know about Go, is that it is designed for concurrency. No introduction to Go is complete without a demonstration of its goroutines and channels.

But when people hear the word concurrency they often think of parallelism, a related but quite distinct concept. In programming, concurrency is the composition of independently executing processes, while parallelism is the simultaneous execution of (possibly related) computations. Concurrency is about dealing with lots of things at once. Parallelism is about doing lots of things at once.

https://go.dev/blog/waza-talk