54 lines
1.9 KiB
Markdown
54 lines
1.9 KiB
Markdown
# What is JRuby?
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JRuby (http://www.jruby.org) is an implementation of Ruby
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(http://www.ruby-lang.org) on the JVM.
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Ruby is a dynamic, reflective, object-oriented, general-purpose, open-source
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programming language. According to its authors, Ruby was influenced by Perl,
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Smalltalk, Eiffel, Ada, and Lisp. It supports multiple programming paradigms,
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including functional, object-oriented, and imperative. It also has a dynamic
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type system and automatic memory management.
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> [wikipedia.org/wiki/Ruby_(programming_language)](https://en.wikipedia.org/wiki/Ruby_(programming_language))
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JRuby leverages the robustness and speed of the JVM while providing the same
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Ruby that you already know and love.
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With JRuby you are able to take advantage of real native threads, enhanced
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garbage collection, and even import and use java libraries.
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%%LOGO%%
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# How to use this image
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## Create a `Dockerfile` in your Ruby app project
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FROM jruby:1.7-onbuild
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CMD ["./your-daemon-or-script.rb"]
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Put this file in the root of your app, next to the `Gemfile`.
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This image includes multiple `ONBUILD` triggers which should be all you need to
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bootstrap most applications. The build will `COPY . /usr/src/app` and `RUN
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bundle install`.
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You can then build and run the Ruby image:
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docker build -t my-ruby-app .
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docker run -it --name my-running-script my-ruby-app
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### Generate a `Gemfile.lock`
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The `onbuid` tag expects a `Gemfile.lock` in your app directory. This `docker
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run` will help you generate one. Run it in the root of your app, next to the
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`Gemfile`:
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docker run --rm -v "$PWD":/usr/src/app -w /usr/src/app jruby:1.7 bundle install --system
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## Run a single Ruby script
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For many simple, single file projects, you may find it inconvenient to write a
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complete `Dockerfile`. In such cases, you can run a Ruby script by using the
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Ruby Docker image directly:
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docker run -it --rm --name my-running-script -v "$PWD":/usr/src/myapp -w /usr/src/myapp jruby:1.7 jruby your-daemon-or-script.rb
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