Telegrams

Telegrams is a clustered message bus.

Getting Started

Requirements

• Erlang (R15B01 or later)
• Rebar

You will need rebar installed in your $PATH.

Please see the rebar repository for downloading and building instructions.

Install the project

$ git clone https://github.com/tOkeshu/telegrams.git
$ cd telegrams
$ make app

These commands should pull the Erlang dependencies via Rebar and build a release.

Start a node

$ ./rel/telegrams/bin/telegrams start # listening on 8353
$ curl http://localhost:8353/my/chan/nel -N

in another terminal

$ curl -X POST http://localhost:8353/my/chan/nel --data-binary "hello"
$ curl -X POST http://localhost:8353/my/chan/nel --data-binary " world!"

and see the data appears in the first terminal.

Cluster

Telegrams can work as a cluster. For this you need to configure multiple nodes.

Same machine

For tests purpose it could be relevant to launch multiple nodes on the same machine. To do this, edit vm.args and sys.config in rel/files:

$ vim rel/files/vm.args rel/files/sys.config
$ grep sname rel/files/vm.args
-sname telegrams1@host1
$ grep port rel/files/sys.config
 {telegrams, [{port, 8353}]},

Build the application and copy the release to a specific directory:

$ make app && cp rel/telegrams rel/telegrams1

Do the same for the second node but with a different sname and port:

$ vim rel/files/vm.args rel/files/sys.config
$ grep sname rel/files/vm.args
-sname telegrams2@host1
$ grep port rel/files/sys.config
 {telegrams, [{port, 8354}]},
$ make app && cp rel/telegrams rel/telegrams2

Now start the two nodes and listen from one of them:

$ ./rel/telegrams1/bin/telegrams start
$ ./rel/telegrams2/bin/telegrams start
$ curl http://localhost:8353/my/chan/nel -N # also works with 8354

in another terminal

$ curl -X POST http://localhost:8353/my/chan/nel --data-binary "from first node "
$ curl -X POST http://localhost:8354/my/chan/nel --data-binary "from second node"

Now play with it, grab a beer and chill...

Different machines

With different machines, you need to edit hosts in rel/files/hosts:

$ cat rel/files/hosts
'host1'.
'host2'.

$ # don't forget the newline at the end

Then you need to reproduce the same steps as for one machine, except you don't need to create a specific directory and can use the same port everywhere.

License

Telegrams are released under the terms of the GNU Affero General Public License v3 or later.