PUT and DELETE - RESTful API Express MongoDB Mongoose - node.js

Question

First time posting. I'm building a blog site and using Node.js, Express.js, MongoDB, and Mongoose for my back-end. GET and POST work for getting and creating posts. However, PUT and DELETE are not working when using POSTMAN as I get "Cannot DELETE(PUT) /api/blog". I feel like it's related to routes, particularly when I'm trying to findById (/api/blog/:blog_id).
Server.js
var express = require('express');
var mongoose = require('mongoose');
var port = process.env.PORT || 8080;
var logger = require('morgan');
var favicon = require('serve-favicon');
var bodyParser = require('body-parser');
var methodOverride = require('method-override');
var app = express();
mongoose.connect('mongodb://127.0.0.1:27017/blog');
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error: '));
db.once('open', function callback () {
console.log("Scrolls are ready to be written!!!");
});
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.json({ type: 'application/vnd.api+json' }));
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.text());
app.use(methodOverride());
app.use(express.static(__dirname + '/client'));
app.use(function(req, res, next) {
res.header('Access-Control-Allow-Origin', '*');
res.header('Access-Control-Allow-Methods', 'OPTIONS, GET, POST, PUT, HEAD, DELETE');
res.header('Access-Control-Allow-Headers', 'X-Requested-With, X-HTTP-Method-Override, content-type, Accept');
next();
});
// *Routes*
require('./app/routes.js')(app);
// *App Start*
// http://localhost:8080
app.listen(port);
console.log('Connected to port ' + port);
exports = module.exports = app;
app/routes.js
var Blog = require('./models/blog');
module.exports = function(app) {
// *Server Routes*
// Place API calls here
// Place Authentication routes here
//var express = require('express');
//var router = express.Router();
// *API Routes*
// Uses Mongoose to GET all Blog Posts from database
app.get('/api/blog', function(req, res, next) {
Blog.find(function(err, blog) {
// If error
if (err) return next(err);
//res.send(err);
res.json(blog);
});
});
// Uses Mongoose to POST new Blog Posts in database
app.post('/api/blog', function(req, res) {
Blog.create({
title: req.body.title,
body: req.body.body,
author: req.body.author,
comments: req.body.comments,
likes: req.body.likes,
dislikes: req.body.dislikes,
image: req.body.image,
createdOn: req.body.createdOn
}, function(err, blog) {
if (err)
res.send(err);
Blog.find(function(err, blog) {
if (err)
res.send(err)
res.json({ message: 'Blog Post Created!' });
});
});
});
// Uses Mongoose to GET Blog Post by _id from database
app.get('/blog/:blog_id', function(req, res) {
Blog.findById(req.params.blog_id, function(err, blog) {
if (err)
res.send (err);
res.json(blog);
});
})
// Uses Mongoose to PUT updates for Blog Posts by _id in database
app.put('/blog/:blog_id', function(req, res) {
Blog.findById(req.params.blog_id, function (err, blog) {
if (err) res.send(err);
if (req.body.title) blog.title = req.body.title;
if (req.body.body) blog.body = req.body.body;
if (req.body.author) blog.author = req.body.author;
if (req.body.comments) blog.comments = req.body.comments;
if (req.body.likes) blog.likes = req.body.likes;
if (req.body.dislikes) blog.dislikes = req.body.dislikes;
if (req.body.image) blog.image = req.body.image;
if (req.body.createdOn) blog.createdOn = req.body.createdOn;
blog.save( function (err) {
if (err) send (err);
res.json({message: 'Blog Post Updated!'});
});
});
});
// Uses Mongoose to DELETE Blog Posts by _id in database
app.delete('/blog/:blog_id', function(req, res) {
Blog.remove({
_id: req.params.blog_id
}, function (err, blog) {
if (err) return res.send(err);
res.json({ message: 'Blog Post Deleted'});
});
});
// API's for PUT, POST, DELETE go here
// *Frontend Routes*
// Route to handle all AngularJS requests
app.get('*', function(req, res) {
res.sendfile('./client/views/index.html');
});
};