Tempdir option

[rylwin]

I needed to add a way to set the tmpdir used during bursts to avoid a race condition where the single pages would be overwritten. I implemented this by allowing users to pass a :tmpdir option. If none is provided, it defaults to Dir.tmpdir, which is what the code was previously using. Please merge this if you think this is a good addition.

Also, note that there is also a commit in this pull request that adds a require for 'digest'. I added this because I got errors when running the tests when digest was not required, so please cherry-pick around this commit if necessary.

And thanks for your work on active_pdftk!

[tcocca]

Hi, thanks for your interest in the project. I will definitely check out this PR. This is an interesting option to be able to set the tmpdir.

What OS/Ruby are you on where you are getting the digest errors? I have tested on os x 10.6 ree and 1.9.2 and ubuntu 1.8.7/1.9.2.

I would love to get a travis-ci set up for the project but I'm not sure how I could get the pdftk lib installed to be able to run the tests.

Thanks again, hopefully I'll have some time to spend on this project this weekend.

[tcocca]

The other thing I would love to be able to do is use Dir.chdir to get into the tmpdir, which is supported by popen3 in version 1.9.2 and up http://apidock.com/ruby/Open3/popen3 but I don't know how to make it work for 1.8.7 / ree w/out pre-pending it to the command? Any ideas?

~ Tom

[rylwin]

Upon further examination of the "digest" issue, I realized it was only required for the custom matchers, so I moved the requires to the spec_helper.rb. I'm running ubuntu and I had the issue with ree and 1.9.2. Not sure if this matters but I use rvm to manage my rubies. It's certainly strange that I'm getting those errors and you aren't.

travis-ci allows you to install packages via apt-get. Check out http://about.travis-ci.org/docs/user/build-configuration/. There is a section titled "Installing Packages Using apt" that may be of interest.

With respect to chdir, I played with this a bit and if you do:

Dir.chdir(tmpdir)
Open3.po...

Then this will use the provided tmpdir without prepending cmd. Now you can't pass :chdir like in 1.9.2, but it seems like you could use this code for all versions of ruby.