Getting a file location and name...

[Joe Van Dyk]

Hi,

Say I have /joe/configuration/config.rb:
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D
puts "this configuration file is located in this directory: " +
File.dirname( ????? )
eval File.read(File.dirname( ?????? ) + "/common.rb")
# other stuff
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D

common.rb is located in /joe/configuration. It also contains some Ruby cod=
e.


The main program looks something like this:
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D
config_file =3D ARGV.shift
eval File.read config_file
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D

And I'd start the program via 'ruby main.rb /joe/configuration.rb'.

So, I have a main program that reads in a Ruby configuration file that
can also read other configuration files that are in a relative
directory. I'm having problems with the relative directory part. If
I hardcode the directory paths, everything's ok. But I don't want
/joe/configuration/config.rb to know that it's in /joe/configuration.=20
I just want that configuration file to be able to read
/joe/configuration/common.rb.

Sorry if this is confusing, let me know if I can clarify the question.

Joe

 

[Ryan Leavengood]

So, I have a main program that reads in a Ruby configuration file that
can also read other configuration files that are in a relative
directory. I'm having problems with the relative directory part. If
I hardcode the directory paths, everything's ok. But I don't want
/joe/configuration/config.rb to know that it's in /joe/configuration.
I just want that configuration file to be able to read
/joe/configuration/common.rb.

Sorry if this is confusing, let me know if I can clarify the question.

Don't worry Joe, this is a common problem, and fairly easily solved.
All you have to do is use Ruby's built-in library search path code,
with a special addition:

config.rb:

# Adds the directory containing this code to the search path
$:.unshift File.dirname(File.expand_path(__FILE__))
# Now require will work
require 'common'

Ryan

 

[Joel VanderWerf]

Hi,

Say I have /joe/configuration/config.rb:
==============================
puts "this configuration file is located in this directory: " +
File.dirname( ????? )
eval File.read(File.dirname( ?????? ) + "/common.rb")
# other stuff
==============================

common.rb is located in /joe/configuration. It also contains some Ruby code.


The main program looks something like this:
==============================
config_file = ARGV.shift
eval File.read config_file
==============================

And I'd start the program via 'ruby main.rb /joe/configuration.rb'.

So, I have a main program that reads in a Ruby configuration file that
can also read other configuration files that are in a relative
directory. I'm having problems with the relative directory part. If
I hardcode the directory paths, everything's ok. But I don't want
/joe/configuration/config.rb to know that it's in /joe/configuration.
I just want that configuration file to be able to read
/joe/configuration/common.rb.

Sorry if this is confusing, let me know if I can clarify the question.

Joe

What about something like

def with_load_path(path)
$LOAD_PATH.unshift path
yield
ensure
$LOAD_PATH.shift
end

Then use that around your #eval call in the main program, with the
'/joe/configuration' as the argument. Then require should work relative
to the path you gave. (But note that $LOADED_FEATURES will prevent files
with the same name from being loaded again, even if in a different
config dir.)

Not thread safe, but oh well.

Another option: my "script" lib (see RAA). That makes sure that the
global $LOADED_FEATURES doesn't get affected.

 

[Robert Klemme]

Hi,

Say I have /joe/configuration/config.rb:
==============================
puts "this configuration file is located in this directory: " +
File.dirname( ????? )
eval File.read(File.dirname( ?????? ) + "/common.rb")
# other stuff
==============================

common.rb is located in /joe/configuration. It also contains some
Ruby code.


The main program looks something like this:
==============================
config_file = ARGV.shift
eval File.read config_file

IMHO eval is completely superfluous here: just do

load config_file

==============================

And I'd start the program via 'ruby main.rb /joe/configuration.rb'.

So, I have a main program that reads in a Ruby configuration file that
can also read other configuration files that are in a relative
directory. I'm having problems with the relative directory part. If
I hardcode the directory paths, everything's ok. But I don't want
/joe/configuration/config.rb to know that it's in /joe/configuration.
I just want that configuration file to be able to read
/joe/configuration/common.rb.

If those other files do only belong to your config.rb (and are no files that
you wish to require) then you can do this in config.rb

base = File.basename __FILE__

load File.join(base, "common.rb")

File.open(File.join(base, "common.rb") do |io|
....
end

File.open(File.join(base, "etc", "lib", "whatever.conf") do |io|
....
end

Kind regards

robert