Making a Post Route

So far, we have only made GET requests to our server. A POST request can send data securely through the request body. In order to make POST requests, first we need to include the "body-parser" library from our node_modules (included with express). Add these lines after the app variable:

```javascript
const bodyParser = require('body-parser');
app.use(bodyParser.json());
```

Let's write a function to handle a POST request made to the 'login' endpoint, as if a user was trying to log in:
```javascript
app.post('/login',function(req,res){
const username=req.body.username;
const password=req.body.password;

const mockUsername="billyTheKid";
const mockPassword="superSecret";

if (username===mockUsername && password===mockPassword){
res.json({
success: true,
message: 'password and username match!',
token: 'encrypted token goes here'
})
} else {
res.json({
success: false,
message: 'password and username do not match'
})
}
})
```

Your entire file should look like this now:

```javascript
const express = require('express');
const app = express();
const bodyParser = require('body-parser');

app.use(bodyParser.json())

const mockUserData=[
{name:'Mark'},
{name:'Jill'}
]

app.get('/users',function(req,res){
res.json({
success: true,
message: 'successfully got users. Nice!',
users: mockUserData
})
})
// colons are used as variables that be viewed in the params
app.get('/users/:id',function(req,res){
console.log(req.params.id)
res.json({
success: true,
message: 'got one user',
user: req.params.id
})
})

app.post('/login',function(req,res){
// Typically passwords are encrypted using something like bcrypt before sending to database
const username=req.body.username;
const password=req.body.password;

// This should come from the database
const mockUsername="billyTheKid";
const mockPassword="superSecret";

if (username===mockUsername && password===mockPassword){
// In practice, use JSON web token sign method here to make an encrypted token
res.json({
success: true,
message: 'password and username match!',
token: 'encrypted token goes here'
})
} else {
res.json({
success: false,
message: 'password and username do not match'
})
}

})

app.listen(8000,function(){console.log('server is listening')})

```
Time to commit our changes!
```
git add server.js
git commit -m"add login POST route"
git push origin master
```