automatic collection initializing [enhancement]

[ippa]

Hey, great lib! Been searching for exaclty this... looked through tons of mongo node libs. It just makes sense mimicking the shell, why learn 2 different syntaxes?

Anyhow, had a suggestion, couldn't this code:

var db = server.db("awesome_blog")

var posts = db.collection("posts")

var comments = db.collection("comments")

Be replaced with just: var db = server.db("awesome_blog")

... and the collections are automatically detected / initialized, basically that the following would happen behind the scenes:

db.posts = db.collection("posts")

db.comments = db.collection("comments")

... then we access the finders etc with db.posts.find() .. just as in the shell. Wouldn't this mimick the shell even more?

[marcello3d]

The problem with this approach is that V8 doesn't support Proxies, so there's no way to dynamically make db.posts act like db.collection("posts").

While I could get a list of collections on the server and automatically make collections for them, that won't let you create new ones, and it would require you to have an asynchronous callback.

I did a little exploring into the possibility of making server and db functions rather than objects, so you can do server("db")("collections"), but I'm worried that's too clever.

[marcello3d]

So in summary. I agree that would be great, but I don't know how to do it.

[ippa]

A super simple:

var db = server.db("pixelholm")
db.screens = db.collection("screens")

works all good here, but I imagine the problem is a bit more complex on your side.

[marcello3d]

While I don't want to make mongolian deadbeef dependent on native code (nor do I really want two different ways of doing the same thing), this could probably be implemented with Proxies: https://github.com/samshull/node-proxy

[ippa]

The only reason I suggested this is cause node-mongolian does seem to have a goal to be as close to the mongoconsole as possible.

And in the mongoshell I do this:

db.screens.find();

I don't do:

db.collection("screens").find()

Other then that it doesn't matter much to me :)

[marcello3d]

Agreed. It'd be nice, but unfortunately impossible without changing how node works. :-(

[OneOfOne]

I wrote a small patch, which semi-accomplishes this, however you need to pass the collection names to the db constructor. ex : db = new (require('mongolian'))().db('test-db', ['session', 'cache'])

The patch :

diff --git a/lib/db.js b/lib/db.js
index 2502d90..5fce804 100644
--- a/lib/db.js
+++ b/lib/db.js
@@ -6,11 +6,25 @@ var safetyNet = require('./util').safetyNet,
     MongolianCollection = require('./collection'),
     MongolianGridFS = require('./gridfs')

-var MongolianDB = module.exports = function(server, name) {
+var MongolianDB = module.exports = function(server, name, collections) {
     this.server = server
     this.name = name
     this._collections = {}
     this._gridfss = {}
+    if(collections){
+        for(var i in collections) {
+            var n = collections[i];
+            console.log(n, n in this);
+            if(!this[n]){ //so we wouldn't accidently delete a function or something
+                this.__defineGetter__(n, function() {
+                    return this.collection(n);
+                });
+            } else {
+                server.warn('The collection "' + n + '" couldn\'t be set as a direct getter.');
+            }
+
+        }
+    }
 }

 /**
diff --git a/lib/server.js b/lib/server.js
index 0efd88e..cfef952 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -164,9 +164,9 @@ Mongolian.prototype.dbNames = function(callback) {
 /**
  * Get a database
  */
-Mongolian.prototype.db = function(name) {
+Mongolian.prototype.db = function(name, collections) {
     return this._dbs[name] ||
-          (this._dbs[name] = new MongolianDB(this, name))
+          (this._dbs[name] = new MongolianDB(this, name, collections))
 }

 Mongolian.prototype.toString = function() {

[awwright]

That's needlessly complex. If you want to use db.collectionName just do something like:

var db = server.db("database");
['session', 'cache'].forEach(function(n){ db[n]=db[n]||db.collection(n); });

In any event I don't think this is functionality that could make its way into mongolian.

[tarqd]

You could support this now that node/v8 support Proxies via --harmony. Just detect if the Proxy object is available and use it