Deno Example

import { Application, Router } from "https://deno.land/x/oak/mod.ts";


const router = new Router();
router.get("/", (context : any) => {
    context.response.body = "Hello world!";
});


//getUser
router.get("/getUser",(context : any) => {
    try{
        const decoder = new TextDecoder("utf-8");
        const data = Deno.readFileSync("./users.json");
        console.log(decoder.decode(data));
        context.response.body = decoder.decode(data)
    }
    catch(err){
        console.log(err);
        context.response.status = 500;
        context.response.body = err;
    }
    
})  


router.get("/getUser/:id",(context : any) => {
    try{
        const decoder = new TextDecoder("utf-8");
        const data = Deno.readFileSync("./users.json");
        console.log(decoder.decode(data));
        const users = JSON.parse(decoder.decode(data));
        if (context.params && context.params.id && users["user"+context.params.id])
        {
            const user = users["user"+context.params.id];
            context.response.body = user;
        }
        else{
            context.response.status = 404;
            context.response.body = `User with id ${context.params.id} does not exist`;
        }
    }
    catch(err){
        console.log(err);
        context.response.status = 500;
        context.response.body = err;
    }
    
}) 

router.post("/addUser",(context : any) => {
    try{
        const decoder = new TextDecoder("utf-8");
        const data = Deno.readFileSync("./users.json");
        console.log(decoder.decode(data));
        const users = JSON.parse(decoder.decode(data));
        console.log(Object.keys(users).length);
        var len = Object.keys(users).length;
        var user :any = {
            "name":"New User",
            "password":`password${len + 1}`,
            "profession":"webdeveloper",
            "id":len+1
        }

        users["user"+(len+1)] = user;
        console.log(users);
        const encoder = new TextEncoder();
        const updatedUser = Deno.writeFileSync("./users.json",encoder.encode(JSON.stringify(users)));;
        context.response.status = 201;
        context.response.body = "User added successfully";

    }
    catch(err){
        console.log(err);
        context.response.status = 500;
        context.response.body = err;
    }
    
}) 


router.delete("/deleteUser/:id",(context : any) => {
    try{
        const decoder = new TextDecoder("utf-8");
        const data = Deno.readFileSync("./users.json");
        const users = JSON.parse(decoder.decode(data));
        if (context.params && context.params.id && users["user"+context.params.id])
        {
            delete users["user"+context.params.id];
            console.log(users);
            const encoder = new TextEncoder();
            const updatedUser = Deno.writeFileSync("./users.json",encoder.encode(JSON.stringify(users)));;
            context.response.status = 201;
            context.response.body = `User ${context.params.id} deleted successfully`;
        }
        else{
            context.response.status = 404;
            context.response.body = `User with id ${context.params.id} does not exist`;
        }
       

    }
    catch(err){
        console.log(err);
        context.response.status = 500;
        context.response.body = err;
    }
    
}) 

router.put("/updateUser/:id",async (context : any) => {
    try{
        const decoder = new TextDecoder("utf-8");
        const data = Deno.readFileSync("./users.json");
        const users = JSON.parse(decoder.decode(data));

        const body =  await context.request.body().then((user : Object) => user);
        if (context.params && context.params.id && users["user"+context.params.id] && body.value )
        {
            const user = users["user"+context.params.id];
           for( let [key,value] of Object.entries(user)){
               if(key !== "id"){
                  if(body.value[key]){
                       user[key] = body.value[key]
                   }
               }
            }
            users["user"+context.params.id] = user
            const encoder = new TextEncoder();
            Deno.writeFileSync("./users.json",encoder.encode(JSON.stringify(users)));;
            context.response.status = 200;
            context.response.body = `User ${context.params.id} updated successfully`;
        }
        else{
            context.response.status = 404;
            context.response.body = `User with id ${context.params.id} does not exist`;
        }
    }
    catch(err){
        console.log(err);
        context.response.status = 500;
        context.response.body = err;
    }
    
})


const app = new Application();
app.use(router.routes());
app.use(router.allowedMethods());
console.log("Server is running on address : http://localhost:8000")
await app.listen({ port: 8000 })

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