# Passing data to rant/rake for a customized build? **URL:** \ **Category:** Ruby\ **Created:** [March 20, 2007, 7:51pm UTC](https://www.ruby-forum.com/t/passing-data-to-rant-rake-for-a-customized-build/89475 "2007-03-20T19:51:26Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![phrogz](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/2acd7d/32.png) [@phrogz](https://www.ruby-forum.com/u/phrogz)\ **Post date:** [March 20, 2007, 7:51pm UTC](https://www.ruby-forum.com/t/passing-data-to-rant-rake-for-a-customized-build/89475/1 "2007-03-20T19:51:26Z")
Summary: How do I use a single rantfile or rakefile to perform some varying commands based on data that I want to pass to it? Background: My company makes a Windows-based middleware product helping next-gen game developers create UIs. In the process of creating the UI, our tool gathers information about the raw 3D models and 2D images and data files and so forth needed to create the end result. When the artist presses the “Preview” button, the application needs to essentially perform a ‘build’ process. Various assets are conditioned (going from bloated formats to runtime-appropriate binaries) using various standalone applications. Only those resources that have changed want to be conditioned, and thus some dependency management is needed to do as little work as possible as quickly as possible. Depending on the target platform, some files may need to be copied over the network to the PS3 or 360 dev kit. The final ‘product’ of the build is launching the preview application and passing it some descriptor to show the end result. The process changes slightly based on: - debug/release mode, - the target platform to preview on, - the actual project being worked on and the assets it contains …but otherwise is the same for every project file, for a given customer. Each customer, however, may change the process entirely. Question: I’m looking at Rant (or perhaps Rake) for this right now.[1] The idea is that the application would run a Rant target (perhaps based on a combination of debug/release and target platform), which would kick off all the conditioners as appropriate and finally launch the viewer application. My question is…how do I pass data to a rantfile? The command line for rant is just: rant [-f Rantfile] [Options] [targets] which gives me no way of simply passing along the name of the project and other assets from our tool. Is the best choice to have our tool write out a text file manifest of all the assets of the various types, and have Rant tasks use that? [This would sort of match the ability of make (or rant) to derive dependencies from files with a known format (like C includes).] Do I build a folder structure and copy/alias all the resources into known buckets and have Rant enumerate the directories? (I’d have to copy the rantfile into the right spot to set the context to run with.) [This would match the _.c-\>_.o type mentality.] Do I use something like ERB and have a rantfile template (editable by customers) that our tool can use to dynamically customize the rantfile on each preview command? Is the rant “gen” method (that I don’t yet understand) the answer I’m looking for? I’ve only just begun reading the documentation on Rant, and I haven’t used any make system (other than blindly typing “configure/make/make install”) in many, many, many years. Please forgive me (and help) if I’m asking really basic questions. Thanks in advance for any help! [1] I’m also looking at MSBuild, NAnt, and maybe Jam, and maybe others. I’m leaning towards Rant/Rake right now because I think full Ruby-based tasks will provide the power and flexibility game customers will need (no limitations in what can be done) in a clear, clean fashion. ---
**Author:** ![phrogz](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/2acd7d/32.png) [@phrogz](https://www.ruby-forum.com/u/phrogz)\ **Post date:** [March 20, 2007, 8:00pm UTC](https://www.ruby-forum.com/t/passing-data-to-rant-rake-for-a-customized-build/89475/2 "2007-03-20T20:00:28Z")
On Wed, 21 Mar 2007, Phrogz wrote: > binaries) using various standalone applications. Only those resources > > - the actual project being worked on and the assets it contains > My question is…how do I pass data to a rantfile? The command line > for rant is just: > rant [-f Rantfile] [Options] [targets] > which gives me no way of simply passing along the name of the project > and other assets from our tool. why not via the environment? you may also be able to pass stdin rant rantifle \< stdin and then have a ‘configuration’ task, which all other tasks depend on, which does something like Config = YAML.load STDIN.read this stdin bit is a wild ass guess, however. cheers. -a ---
**Author:** ![phrogz](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/2acd7d/32.png) [@phrogz](https://www.ruby-forum.com/u/phrogz)\ **Post date:** [March 20, 2007, 8:02pm UTC](https://www.ruby-forum.com/t/passing-data-to-rant-rake-for-a-customized-build/89475/3 "2007-03-20T20:02:28Z")
On Mar 20, 12:45 pm, “Phrogz” [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Do I use something like ERB and have a rantfile template (editable by > customers) that our tool can use to dynamically customize the rantfile > on each preview command? > > Is the rant “gen” method (that I don’t yet understand) the answer I’m > looking for? I left off one other option I had thought of: setting one or more environment variables with the data in question before kicking off the build. It’s nice because there’s no file I/O needed, but it prevents the preview from being launched by anything but our tool. Command-line preview/nightly builds are also desirable. ---
**Author:** ![phrogz](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/2acd7d/32.png) [@phrogz](https://www.ruby-forum.com/u/phrogz)\ **Post date:** [March 21, 2007, 5:20am UTC](https://www.ruby-forum.com/t/passing-data-to-rant-rake-for-a-customized-build/89475/4 "2007-03-21T05:20:25Z")
Phrogz wrote: > > > > the preview from being launched by anything but our tool. Command-line > preview/nightly builds are also desirable. You might not be aware of this, but rake accepts env vars with this syntax: rake e1=v1 e2=v2 … task … For example: $ cat rakefile task :bar do p ENV[‘foo’] end $ rake foo=3 bar (in /tmp) “3” Maybe rant has the same feature?