Add support for Mongos topology

[kapetan]

mongodb-core also supports the Mongos topology, which is not exposed by mongojs.

Maybe lib/get-topology.js should also be a able to return an Mongos instance.

[saintedlama]

Implemented a very experimental version in branch saintedlama/mongos https://github.com/mafintosh/mongojs/tree/saintedlama/mongos would be awesome if you could give that version a try (= alpha test)

[kapetan]

That was fast. I gave it a try, and I can connect and retrieve documents, but it throws a type error when trying to close the database.

The script I used.

var mongojs = require('mongojs');

var connection = '...';
var options = {
    mongos: true,
    ssl: true,
    sslValidate: false,
    rejectUnauthorized: false,
    authMechanism: 'ScramSHA1'
};

var db = mongojs(connection, ['appUsers'], options);

db.appUsers.findOne({}, function(err, user) {
    console.log(user); // Returns the user
    db.close(); // Call to close throws a TypeError
});

The stack of the error.

/private/tmp/mj/node_modules/mongojs/node_modules/mongodb-core/lib/cursor.js:247
      throw err;
            ^
TypeError: Object [object Object] has no method 'destroy'
    at /private/tmp/mj/node_modules/mongojs/lib/database.js:66:12
    at apply (/private/tmp/mj/node_modules/mongojs/node_modules/thunky/index.js:16:28)
    at null._getServer (/private/tmp/mj/node_modules/mongojs/node_modules/thunky/index.js:27:3)
    at Database.close (/private/tmp/mj/node_modules/mongojs/lib/database.js:64:8)
    at /private/tmp/mj/index.js:15:5
    at /private/tmp/mj/node_modules/mongojs/lib/collection.js:51:5
    at handleCallback (/private/tmp/mj/node_modules/mongojs/node_modules/mongodb-core/lib/cursor.js:244:5)
    at nextFunction (/private/tmp/mj/node_modules/mongojs/node_modules/mongodb-core/lib/cursor.js:739:5)
    at /private/tmp/mj/node_modules/mongojs/node_modules/mongodb-core/lib/cursor.js:664:7
    at queryCallback (/private/tmp/mj/node_modules/mongojs/node_modules/mongodb-core/lib/cursor.js:321:5)

[saintedlama]

Could you give it a try with a non auth mongos connection. I guess this could narrow issue issue #224 - I suspect the error to arise only in auth environments

[saintedlama]

Any update?

[kapetan]

Sorry I didn't answer sooner, but I didn't have a mongos setup without authentication running, and I didn't have the time to try to set it up locally. I'll see if I can do it one of these days.

[saintedlama]

👍 great thanks for your help

[saintedlama]

Should be fixed in version 2.0 (released just some seconds ago)