Node JS training

Typescript Basics

1. Create a Connection interface with open and close methods open (url, login , password )--> password as optional parameter -> console.log("method name , parameters...)

2. Create two classes OracleConnection and SQLConnection implementing connection class

3. Test the code

4. Create

   Emp (empno, ename, salary) class Emp { empno: number; ename: string salary: number }

5. Create EmpDAO class constructor to accept Connection object Variable - arr:Array = new Array() Methods Insert - accept Emp object -> con.open(); console.log("in insert"); con.close() List - list the employees.

Express Setup with TypeScript

1. create a folder expressjs

2. on cmd prompt execute

    `npm init -y`
   

3. Option 1-

        npm install --save-dev [email protected]
        npm install --save-dev [email protected]
        npm install --save [email protected]
        npm install --save-dev @types/[email protected]
   

4. Option 2 - modify package.json to include

        "devDependencies": {
            "@types/express": "^4.16.1",
            "tslint": "^5.12.1",
            "typescript": "^3.3.3"
            },
        "dependencies": {
            "express": "^4.16.4"
            }
   

and invoke

`npm install`

node_modules\.bin\tsc.cmd -init

node_modules\.bin\tslint.cmd –init (tslint.json)

Modify package.json To include script line

    ` "start": "tsc && node dist/index.js" `

Starting server:

    `npm start`