Re: Including gems in a bundle with Rawr (Jruby)

On Feb 23, 2010, at 10:28 AM, Eric Christopherson wrote:
> On Mon, Feb 22, 2010 at 12:28 AM, James Britt  
> <[e-mail]> wrote:
>> Eric Christopherson wrote:
>>>
>>> OK. I was able to get it to load Barby, but I had to add
>>> 'lib/ruby/barby/lib' to my $LOAD_PATH. I don't understand the  
>>> purpose
>>> of unpacking the gem into lib/ruby specifically, when it could  
>>> reside
>>> anywhere within the hierarchy.
>>
>> Wherever you want to place it, you have to be sure that the load path
>> includes it. The rawr build_config has lib/ruby by default, I  
>> believe. (You
>> need to indicate what local paths to set for $: in your code, but  
>> also what
>> folders should be packaged up by rawr, and how they should be  
>> structured in
>> any resulting jar file.)
>
> OK. I put this at the top of my script:
>
> $LOAD_PATH << 'lib/ruby/barby/lib'
> $LOAD_PATH << 'lib/ruby/prawn/lib'
> $LOAD_PATH << 'lib/ruby/prawn-core/lib'
> $LOAD_PATH << 'lib/ruby/prawn-layout/lib'
> $LOAD_PATH << 'lib/ruby/prawn-security/lib'

(Disclaimer: This answer is based solely on Ruby knowledge, not JAR  
behavior or JRuby)

Does it work if you do:

$LOAD_PATH.unshift 'lib/ruby/prawn-security/lib'
$LOAD_PATH.unshift 'lib/ruby/prawn-layout/lib'
$LOAD_PATH.unshift 'lib/ruby/prawn-core/lib'
$LOAD_PATH.unshift 'lib/ruby/prawn/lib'
$LOAD_PATH.unshift 'lib/ruby/barby/lib'

this puts your directories at the front

-Rob

> This allows the jarred script to run -- but I later realyzed that it's
> still reading the files from the filesystem. If I run the jar from a
> different directory, or if I move or delete the lib directory, it is
> unable to load them.
>
> Questions:
> 1. How do I add libraries *inside the jar* to my $LOAD_PATH?
> 2. Is there a more elegant way to add them than to just list each one
> at the top of my script? I thought the manifest.rb file was supposed
> to take care of this, but it doesn't.
> 3. What is actually supposed to go in manifest.rb?
>
>>
>> Technically, you can set this up as you like, but it's far easier  
>> to use and
>> to explain using some rawr conventions then saying, abstractly, you  
>> can set
>> up your sub-dirs and load path almost any way you like. Because, as  
>> it
>> happens, you have to be careful, since (as the page explains) code  
>> inside
>> gems sometimes makes assumptions about it's parent directories and  
>> such.
>>
>> For example, I had trouble using the 'builder' code.  It came down  
>> to there
>> being 2 builder.rb files.  One would load the other.  But if $: is  
>> not set
>> up correctly, then the wrong one may be found first, with annoying  
>> results.
>>  (And I'm pretty sure I wrote an earlier version of the page under
>> discussion precisely because of these issues.)
>
> OK.
>
>>
>>>
>>>> If you have code that is attempting to load a gem instead of  
>>>> trying to
>>>> load
>>>> files out of your bundled app then something is likely wrong.
>>>>
>>>> (Note that the example code on that help page never makes use of
>>>> rubygems.
>>>>  Only plain old 'require'.)
>>>>
>>>> Some gems contain code that makes a call to "require 'rubygems'".  
>>>> (There
>>>> was
>>>> a previous thread on ruby-talk about how inane this is.)
>>>
>>> Yes, and I see now that prawn (which I also need) does just that. :(
>>
>> GREG!  on noes ...  :)
>
> Interestingly, prawn works just fine as long as the prawn directories
> are available on the file system -- even though it does a "require
> 'rubygems'". (I've even uninstalled the actual prawn gems and it still
> works.)
>
>>
>>>
>>>> I usually hate to tell people "don't do that" when they ask how  
>>>> do do
>>>> something, but trying to use rubygems from inside an app packaged  
>>>> up with
>>>> rawr is just asking for trouble.  One of the purposes of rawr is  
>>>> create
>>>> self-sufficient apps.
>>>
>>> That's what I want to do: make a program (that uses some gems) and
>>> package them all together so they don't need to be installed
>>> separately. I must be misunderstanding the intention of the page  
>>> we're
>>> discussing; I thought it was about doing that.
>>
>> The page is setting up unpacked gem files in an app.  (The larger  
>> premise of
>> rawr is that the app has a main file, with all other required files  
>> being
>> included in subdirectories or jars, all bundled up in such a way  
>> that Java
>> can execute it. )
>>
>> rawr can build installers for your app that makes sure all the  
>> related files
>> get put in place.
>>
>> But you have to unbundle any gems used by your code. And at that  
>> point, you
>> should thinking of them as gems, and simply as libs that live in a
>> subdirectory of your application folder.
>

Rob Biedenharn		http://agileconsultingllc.com
[e-mail]