Connecting to dokku-rethinkdb

[aleclarson]

Using dokku config:get my-app RETHINKDB_URL
returns rethinkdb://dokku-rethinkdb-foo:28015/my-app
but how should I pass that to the driver?

The following code fails to connect:

const rethinkdb = require('rethinkdb')
const r = rethinkdb({
  host: 'rethinkdb://dokku-rethinkdb-foo/foo',
})

Here's the error:

Failed to connect to rethinkdb://dokku-rethinkdb-foo/foo:28015

I also tried host: 'rethinkdb://dokku-rethinkdb-foo:28015/foo' but it did not work.

[josegonzalez]

If your driver doesn't understand how to read a DSN, then you'll need to parse the DSN and set the properties manually.

[aleclarson]

Surprisingly, neither the official Javascript driver, nor neumino/rethinkdbdash support such a thing.

[aleclarson]

It doesn't seem like my app container has access to rethinkdb.

Here's what I did:

dokku apps:create my-app
dokku rethinkdb:create foo
dokku rethinkdb:link foo my-app
dokku enter my-app
node
> var socket = net.connect('rethinkdb://dokku-rethinkdb-foo:28015/foo');
> Error: connect ENOENT rethinkdb://dokku-rethinkdb-foo:28015/foo

And dokku rethinkdb:info foo returns:

=====> Container Information
       Config dir:          /var/lib/dokku/services/rethinkdb/foo/config
       Data dir:            /var/lib/dokku/services/rethinkdb/foo/data
       Dsn:                 rethinkdb://dokku-rethinkdb-foo:28015/foo
       Exposed ports:       28015->2937 29015->17420 8080->11337 
       Id:                  bd03ee2c4efe00d8ab06b6c2551811f20cc7362b49f979a162a349ca689a33fd
       Internal ip:         172.17.0.2               
       Links:               my-app                    
       Service root:        /var/lib/dokku/services/rethinkdb/foo
       Status:              running                  
       Version:             rethinkdb:2.3.5

Is there anything I can do to test this connection outside of node?

[aleclarson]

Using curl http://172.17.0.2:8080, I've confirmed that my container can access rethinkdb.

I'm still interested in why the DSN can't be connected to.

Is it reliable to hard code the internal IP into my application?

[aleclarson]

Found a way to convert dokku-rethinkdb-foo into 172.17.0.2:

dns.lookup('dokku-rethinkdb-foo', function(error, host) {
  console.log(host); // '172.17.0.2'
})

I guess that will have to do for now.

[aleclarson]

Hmm, still cannot connect.

var socket = net.connect('http://172.17.0.2:28015/foo');
// Error: connect ENOENT http://172.17.0.2:28015/foo

Btw, I can guarantee net.connect is the right method of connecting, since that's what the official RethinkDB driver uses.

[aleclarson]

Okay, I can get it connected to http://172.17.0.2:28015 like so:

var socket = net.connect('28015', '172.17.0.2');

Now is it necessary to connect to /foo, or am I allowed to leave that out?
If it's required, I'm not sure how to do that. Can't find anything on Google.

[aleclarson]

Hmm, the RethinkDB driver seems to be working, despite connecting to http://172.17.0.2:28015 (without the /foo part).

So I guess it's not required? Wasted a lot of time thinking it was required. 😢

[josegonzalez]

my-app would be your "database" or whatever rethinkdb calls that.

[aleclarson]

Oh okay. It doesn't look like it's working correctly.

Using dbList in the web UI says there's no foo database.

r.dbList().run()
// [
//   "rethinkdb" ,
//   "test"
// ]

[aleclarson]

@josegonzalez Have you looked into why the foo database is not being created as expected?

I'm assuming dokku-rethinkdb never supported such a thing. AFAIK, it would require the Python client driver. Does this repo use that at all?

[josegonzalez]

Guess we don't create the database. You can file an issue for that, seems we can do it via rql as shown here.

I likely won't work on the issue since I don't use rethinkdb, but if you'd like to contribute that enhancement, that would be wonderful.