How to use ruby script/console to debug methods in application.rb?

Rails
1

Hello everyone,

newbie question:

I have a couple of methods that interact with a remote python server
in application.rb.
Is there a convenient way to debug them? e.g. run them from “ruby
script/console” - debug-console and see the return values?

Example-method:

def addUserToServer?(category_name, useremail_address)
socket = TCPSocket.open(host, port)
cmd = “COMMAND:adduser;;CAT:” + (category_name,
cmd += “;;EMAIL:” + useremail_address
socket.puts(cmd)
result = socket.rcv(1024)
socket.close()
end

I’d like to see contents of result f.ex. and then return true or false
accordingly.

Rails is version 2.2.2

Any help on this or some other best practice to check those methods is
appreciated.

Lukas

2

lukas wrote:

Hello everyone,

newbie question:

I have a couple of methods that interact with a remote python server
in application.rb.
Is there a convenient way to debug them? e.g. run them from “ruby
script/console” - debug-console and see the return values?

Just set a breakpoint, run script/server -u, and play around in the
debugger.

Example-method:

def addUserToServer?(category_name, useremail_address)

That should be add_user_to_server. camelCase is considered poor style
in Ruby.

socket = TCPSocket.open(host, port)
cmd = "COMMAND:adduser;;CAT:" + (category_name,

You know you’ve got mismatched parentheses, right? And string
concatenation is more efficient with the “#{}” syntax.

cmd += ";;EMAIL:" + useremail_address
socket.puts(cmd)
result = socket.rcv(1024)
socket.close()

You don’t need empty parentheses when a function doesn’t take arguments.
Frankly, your code looks more like Java than Ruby.

end

I’d like to see contents of result f.ex. and then return true or false
accordingly.

Rails is version 2.2.2

Any help on this or some other best practice to check those methods is
appreciated.

Test-first development will reduce the need for debugging.

Lukas

Best,
–Â
Marnen Laibow-Koser
http://www.marnen.org
[email protected]

3

Marnen,

thanks for your feedback.
Indeed, I’m a newbie ruby programer. I’ll keep your advice in mind.

I was just hoping I could run the method from the debugging console
and check the output directly.

4

Hi Lukas,

You definitely can, by adding some temporary debug puts calls
interspersed in your method, and then calling your method either
using ./script/runner or from within a ./script/console session.

To make that method easier to test, I’d relocate that method outside
of ./app/controllers/application.rb and put it somewhere else, maybe
something like ./app/models/remote_socket_server.rb.

Possibly lame example, but:

add tmp debug calls to meth you want to test:

$ cat ./app/models/remote_socket_server.rb
class RemoteSocketServer

HOST = …
PORT = …

def RemoteSocketServer.add_user(category, email)
puts(“add_user: category=#{category} email=#{email}”) #DEBUG
socket = TCPSocket.open(HOST, PORT)
…
end
…
end

start console and call the meth:

$ ./script/console
…

RemoteSocketServer.add_user(“Stuff”, “[email protected]”)
add_user: category=Stuff [email protected]
…

or run the meth via runner:

$ ./script/runner ‘RemoteSocketServer.add_user(“Stuff”,
“[email protected]”)’
add_user: category=Stuff [email protected]
…

Also note that instead of using puts to stdout, you could change those
debug puts calls to use the environment’s logger instead:

...
 ActionController::Base.logger.debug("add_user:

category=#{category} email=#{email}") #DEBUG
…

such that when that meth is called (via console, runner, or in the web
app), you can just look at the env log:

$ tail -100 ./log/development.log | grep “^add_user”
add_user: category=Stuff [email protected]
…

Once you’re done with your temp testing of the meth, just wipe out
those debug puts/logger calls.

Jeff

5

Thanks Jeff,

it worked. We’ve been able to test the whole stack of methods. :slight_smile:

And I’ve learned something today.

Regards
Lukas

6

lukas wrote:

Marnen,

thanks for your feedback.
Indeed, I’m a newbie ruby programer. I’ll keep your advice in mind.

OK. You’re most welcome.

I was just hoping I could run the method from the debugging console
and check the output directly.

You can. And I explained how. script/console is not a “debugging
console”.

Best,
–Â
Marnen Laibow-Koser
http://www.marnen.org
[email protected]