I was wondering how to load a file from my System Libraries, but I'm not sure how. I was thinking something along the lines of:
require 'gosu'
require "Picture.jpg"
and then having the rest of my code, but every time I try that, I get the error:
No such file to load
I'm not sure if I'm doing something wrong, or there just isn't a way to load a file from my system library into Ruby?
I would suggest you to take close looks at require, load, extend and include.
It will help you to use in your application.
http://ionrails.com/2009/09/19/ruby_require-vs-load-vs-include-vs-extend/
Related
We use Jira/Confluence as our wiki site. I've had a difficult time trying to figure out how to use the add. I'm guessing i'm missing something very obvious. When I go to this site: https://confluence.atlassian.com/display/DISC/Confluence4r to download the confluence4r file, not sure what I'm supposed to do thereafter. The file contains a module which makes sense why it doesn't do anything when running it. But should I being using the gem install functionality in some way? When I simply try to use it in a ruby script, i get the following error:
conf.rb:15:in `<main>': uninitialized constant Confluence (NameError)
Where I am supplying the information required per the script (URL, user & pass contained the correct values when used):
server = Confluence::Server.new("https://collab.sitename.com")
server.login("user", "pass")
puts server.getSpaces()
Any information how to get the working is appreciated.
Confluence4r isn't distributed as a rubygem, it's just a ruby script you can drop onto your filesystem and reference directly.
If you put Confluence4r.rb in the same directory as your own script, you'd need to require it like this:
require './confluence4r.rb'
You shouldn't need the "confluence" and "confluence-client" rubygems to use confluence4r; it's just a very thin wrapper around the Confluence XML-RPC API.
I have a few Ruby scripts that process text files in different ways, that many of my friends find useful. However, most of the people I know are not comfortable running scripts on the command line. The easiest thing for them would be to create a simple webpage where people could upload a file, select a few options, have it processed, and then download the result.
I know it wouldn't be too hard to build something like this in Rails or Merb or something like that, however it seems like a very common problem, so I was wondering if there was already some kind of template, or similar application that I could easily modify, i.e. let the user upload a file, choose a few options, then {fill in code to do something with file}, let the user download the resulting file?
In the past I used Carrierwave to upload user avatars.
If you are used to Rails it's really straightforward.
Let it be a TextFile resource:
gem 'carrierwave'
$ rails g scaffold textfile content:string title:string etc etc
$ rails g uploader textfile
class TextFile < ActiveRecord::Base
attr_accesible :content
mount_uploader :content, TextFileUploader
end
And that is is pretty much all you have to do to obtain the app's skeleton. However, to answer your real question, no, I don't think there is already a rails app that does exactly that.
https://github.com/jnicklas/carrierwave
I found sinatra-fileupload, which pretty perfectly answers my question. It's a very minimalistic framework which works perfectly, I can just plug in the file handling, and change the layout etc a bit. There were many examples of sophisticated Rails plugins linked to databases, with versioning and stuff, but I really wanted the most minimal example.
I have changed this question to better reflect what it is I do not understand.
For example if I try to access the methods in the railties class AppBuilder.
require 'rails/generators/rails/app/app_generator'
g = Rails::AppBuilder.new
puts g.rakefile.inspect
I get an error message activesupport-3.1.3/lib/active_support/secure_random.rb:5:in `': uninitialized constant SecureRandom (NameError)
I do not understand this. Should not each class be "independent" from other classes? Is that not the whole point of object oriented programing?
And now If it is not so more importantly how can I figure out what dependences I need to add? Is it some kind of workflow to solve this? Can I somehow figure out what dependencies to add looking at the documentation? Do this problem have something to do with load path? Can I load all dependences from a gem or rails or whatever? I just don't get it!
doc: http://api.rubyonrails.org/classes/Rails/AppBuilder.html github: https://gist.github.com/rails/rails/blob/master/railties/lib/rails/generators/rails/app/app_generator.rb
there is no easy way to find out which dependencies are used within AppBuilder, cause most of the dependencies are setup somewhere else. so most of the times you need to do some trial and error to get the dependencies right.
the code that you posted has bad style. please get familiar with how to write ruby code properly. buy yourself a book i.e. eloquent ruby or just start reading ruby blogs.
dependencies in ruby is quite simple. every file that you require will be loaded and the load will recurse through the files and then load other requires. the loading will only work if all the required files are on the load path. this load path is similar to your system path and you can add directories to it to tell ruby where to look for files.
in general, there are dedicated entry-points for libraries and their dependencies. those are normally documented, so that if you use them, you get all dependencies right from the beginning. an example for this would be to require 'rails' in order to use rails or require 'active_support/all' if you just want to use active-support. if you wan't to chery-pick files/classes than you are on your own finding out which other classes you need. that part has nothing to do with oop, it's more an dependency-issue (other languages have explicit decleration of dependencies).
in your case, the next step would be to add require "securerandom" to the beginning of your file and then check wich error comes up next.
I was hoping to make a Rails app usable both as an Engine and as a standalone Application.
Specifically, I have a nascent app which I'd like to plug in to a customer's site, but ideally, I'd like to just as easily use the app as a standalone system. However, if config/environments/*.rb exist in the enginified version of my app, I get an Uninitialized Constant error at the time the app that I'm having take a dependency on my engine starts up; Rails complains that the MyEngineModule::Application constant can't be found in development.rb, which I think is simply a load order issue, since this does NOT occur when I run the app standalone. If I delete development.rb, the original initializers that reference my MyEngineModule::Application complain, so then I tried to delete those, and all is well.
Great, except that the original app doesn't work, since its configuration is gone.
Is there some tweak I can make to the initialization load order (or load paths, in the Engine < Rails::Engine class definition) that would prevent the original configs and initializers from being loaded when in an engine context, and allow me to leave them in place for the app context?
The simpler answer is probably this, but I'm feeling stubborn, and would like to know what it would take to make my original goal possible:
extract the code for MyEngine into an engine, remove the config/environments/* files and config/initializers/* files, and make the client app depend on this.
Make a "new" minimalist app depend on MyEngine, and move the environment files and initializers to NewApp.
Assuming I feel some unnatural compulsion to keep my original application runnable as it was, if I want to prevent the "engine" from loading the "application" configuration, what's the best way to handle that? I presume this is only really a problem during development, because I can prevent the environments/*.rb files from being pulled into the gem itself, but I like being able to test locally while I'm developing the engine and its client app.
Continuing my tradition of answering my own esoteric questions, it seems like one passable alternative is to include a guard clause in the engine's environments/*.rb and the initializers that goes something like this:
if defined? CuteEngine::Application
CuteEngine::Application.configure do
config.whatever = something
end
end
This gets around the problem of having two Rails::Application objects at a relatively small cost. Not very happy about it, but I'll live.
Bumping this for new comers.
Rails 3.1 comes with mountable engines, which sounds like exactly what you are describing. The docs aren't great for converting existing code, but it looks like this will do what you want:
module CuteEngine
class Engine < ::Rails::Engine
isolate_namespace CuteEngine
end
end
In your other app's routes.rb file, you'll add:
mount CuteEngine::Engine, at: "/cuteness"
http://edgeguides.rubyonrails.org/engines.html#mounting-the-engine
http://railscasts.com/episodes/277-mountable-engines
I'm working on my first ORM project and am using Mechanize. Here's the situation:
I'm downloading a zip file from my website into a Mechanize::File object. Inside the zip is a file buried three folders deep (folder_1/folder_2/file.txt). I'd like to pull file.txt out of the zip file and return that instead of the zip file itself.
My first thought was to use zip/zipfilesystem. I can do this fine if I save the file to the disk first and use Zip::ZipFile.open(src) but can anyone tell me how/if it is possible to send it over straight from the Mechanize::File.body.
My gut says this has to be possible and I'm just missing something basic. I tried...
zipfile = Mechanize::File.body
Zip::ZipFile.open(zipfile)
...but from what I can tell Zip::ZipFile is only set up to locate a source from a filesystem.
Any direction would be very appreciated and let me know if there are any questions
Thanks in advance
Rob
It seems what you want to do is not possible with rubyzip. From rubyzip library's TODO file:
SUggestion: ZipInputStream/ZipOutputStream should accept an IO object in addition to a filename.