I thought a simple key/value store would be empowering for hackmatch-style products, so I wrote one in node.js, using the popular express library and fs_db, a trivial key/value store that writes to the filesystem. (Mostly this whole thing is a convenience wrapper for fs_db)
The package.json for that was
{
"name": "getput",
"version": "1.0.0",
"description": "trivial persistent keyval GET and PUT",
"main": "index.js",
"dependencies": {
"body-parser": "^1.12.0",
"express": "4.x",
"fs_db": "0.0.4"
}
}
(So if you make a directory, put that package.json in it, and run npm install, it should handle all the dependencies)
I also made two subfolders: public/ (to store some static files to be served up by express) and db/ (for use by fs_db)
My main app was in index.js:
var DB = require( "fs_db" );
var express = require('express');
var bodyParser = require('body-parser');
var app = express();
app.use(bodyParser.json());
// Create a new store, writing data beneath db/.
var store = new DB( "db" );
app.put('/db/:id', function(req, res){
var id = req.params.id;
var data = req.body.value;
console.log(id);
console.log(data);
store.set( id,data );
res.send();
});
app.get('/db/:id', function(req, res){
var id = req.params.id;
store.get( id, function( error, value ) {
res.send(value);
})
});
app.use(express.static(__dirname + '/public'));
app.listen(3000);
console.log('Listening on port 3000');
Once that was in place, I created the js client, getput.js in public/:
function getput(pUrl){
var url = pUrl;
if(url.slice(-1) != '/') url += '/'; //ensure url ends with /
return {
get : function(key,callback){
var newcallback = function(data){
data=(data!="")?JSON.parse(data):null; //"" is unfound
data=(data!="")?JSON.parse(data):null; //"" is unfound
if(callback) callback(JSON.parse(data));
}
this.getraw(key,newcallback);
},
getraw : function(key,callback){
$.get(url+encodeURIComponent(key), function(data){
if(callback) callback(data);
});
},
put : function(key,val,callback){
this.putraw(key,JSON.stringify(val),callback);
},
putraw : function(key,val,callback){
$.ajax({
url: url+encodeURIComponent(key),
data: JSON.stringify({"value":val}),
type: 'PUT',
contentType: 'application/json',
success: function() {
if(callback) callback();
}
});
}
}
}
4 functions are exposed, get()/put() (which assumes you're storing JSON) and getraw()/putraw() (which doesn't). You initialize it with the main url express is listening to. (Hmm- I probably should figure the correct way of having node take an argument from the commandline)
Also in public/ I put this simple tester index.html page:
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>getput tester</title>
<script src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
<script src="getput.js"></script>
<script>
var getrputr = getput("/db");
function put(){
getrputr.putraw($('#key').val(),$('#val').val());
$('#key').val('');
$('#val').val('');
}
function get(){
getrputr.getraw($('#getkey').val(),function(data){
$('#getval').text(data);
});
}
</script>
</head>
<body>
<h1>put</h1>
key: <input id="key"> val: <input id="val">
<button onclick="put();">put</button>
<h1>get</h1>
key: <input id="getkey">
<button onclick="get();">get</button>
<span id="getval"></span>
</body>
</html>
It demonstrates getraw()/putraw().
I run the whole shebang with node or nodemon and bam!
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| clearly, this is why I wish to be a designer/developer hybrid |
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