Dennis v0.3.3 released!

Published: , Will Kahn-Greene | share this (mastodon)
Note: This is an old post in a blog with a lot of posts over a long span of time. The world has changed, technologies have changed, and I've changed. It's likely this is out of date, the code doesn't work, the ideas haven't aged well, or the ideas were terrible to begin with. Let me know if you think this is something that needs updating.

What is it?

Dennis is a Python command line utility (and library) for working with localization. It includes:

  • a translator for strings .po files

  • a linter for finding problems in strings in .po files

v0.3.3 released!

This is the first blog-post-announced release. I think Dennis is good enough for wider use. I've been using it for development work on both kitsune (which drives Support) and fjord (which drives Input with great success.

Why Dennis?

It fills two basic needs I had:

  1. translate .po files so I can find problems during development related to localized strings, layout issues, unicode support, etc

  2. lint translated .po files so that errors in translated strings don't make it to production where they cause fires, make users angry and make me very sad and tired

There's another project called Translate Toolkit that you could use for item 1, but it doesn't have Pirate! and I like my pipeline architecture since it's more "pluggable" (whatever that means). Plus it didn't have a linter that covered my specific issues nor does it return a non-zero exit status so I can't use it for selective compiling.

Therefore I decided to write my own tool to meet my needs.

The ultra-basics

Install

$ pip install dennis
$ pip install blessings  # Optional for prettier output

Linting

Lint a single .po file for problems including mismatched/malformed Python variables in translated strings:

$ dennis-cmd lint locale/fr/LC_MESSAGES/messages.po

Produces output like this:

(dennis) saturn ~/mozilla/fjord> dennis-cmd lint locale/fr/LC_MES
SAGES/messages.po
dennis-cmd version 0.3.4.dev
>>> Working on: /home/willkg/mozilla/fjord/locale/fr/LC_MESSAGES/
messages.po
Error: mismatched: invalid variables: {count}
msgid: Most Recent Message
msgstr[0]: Les {count} derniers messages

Error: mismatched: invalid variables: {count}
msgid: Most Recent Message
msgid_plural: Last %(count)s Messages
msgstr[1]: Les {count} derniers messages

Warning: mismatched: missing variables: %(count)s
msgid: Most Recent Message
msgid_plural: Last %(count)s Messages
msgstr[1]: Les {count} derniers messages

Error: mismatched: invalid variables: {count}
msgid: {0} similar messages
msgstr: Les {count} derniers messages

Warning: mismatched: missing variables: {0}
msgid: {0} similar messages
msgstr: Les {count} derniers messages

Totals
  Warnings:     2
  Errors:       3

If you have blessings installed, it'll colorize that output.

You can also lint a directory structure of .po files:

$ dennis-cmd lint --errorsonly locale/

We use this to compile only the error-free .po files to .mo files and tell us which .po files have problems so we can fix them. This prevents HTTP 500 errors and inaccessible pages due to maltranslated strings on our sites.

Translating

You can translate a .po file in place into Pirate! to help find l10n issues in your code:

$ dennis-cmd translate --pipeline=html,pirate \
    locale/xx/LC_MESSAGES/messages.po

This takes into account that the strings have HTML in them that should be ignored when translating. It uses a pipeline architecture where the output of one transform is fed as input to the next, so you can string them along and get shouty extra-pirate with anglequotes:

$ dennis-cmd translate --pipeline=html,pirate,pirate,shouty,anglequote \
    locale/xx/LC_MESSAGES/messages.po

Summary

That's the gist of it. In the Dennis documentation is a list of Dennis recipes covering linting, translating, etc.

Yay for Dennis!

Want to comment? Send an email to willkg at bluesock dot org. Include the url for the blog entry in your comment so I have some context as to what you're talking about.