Wednesday, May 28, 2014

Another contribution

Joe sent two pull requests for export_excel and print_pisa. Thank you, Joe! I beg your pardon that I still did not find time to have a closer look at them. export_excel would probably be of immediate benefit.

(See also Removed the “Export to .csv” button later on this page.)

Thoughts about versioning and release process

Yesterday I made an upgrade on a Lino Welfare production server, including data migration. So before doing “anything else” I should bump certain version numbers and tag the repositories.

  • Lino Welfare needs a new version number (must change from version 1.1.12 to 1.1.13) because North database migration works using the application’s version number. (Which by the way is an important difference with South or the coming Django migration system, who use an individual “version” counters for every app.)

  • The lino package, north and djangosite need a new version number because they might have influence on the Lino Welfare database structure, and thus Lino Welfare needs to be able to specify “I want this version of lino, of north and/or of djangosite”.

  • The “anything else” above is not absolute. We are talking about changes in trunk/master of djangosite, north, lino and lino_welfare itself. But for example atelier, DavLink and eidreader are special because they have no influence on the database.

  • Changing the version number is itself easy thanks to atelier: I just need to change the project_info.py file, which currently contains:

    SETUP_INFO = dict(
        name='lino-welfare',
        version='1.1.12',  # not yet released
        install_requires=['lino', 'suds', 'vobject', 'django-iban'],
        ...
    

But before actually doing this, I must “release” the current versions.

In fact I don’t need to release them officially on PyPI right now. As long as nobody asks for a new released version, I can save time by skipping this step. But I must be ready to do it retroactively some day in the future.

So I should tag the current state of the involved repositories. To get back into this, I needed to read the Git docs about Tagging

The author of Git Tag Does the Wrong Thing by Default claims that I should not use lightweight tags. And Why should I care about lightweight vs. annotated tags? explains it more in detail.

AlBlue 20110426 writes another interesting must-know about tags:

A tag is like a branch, in that it identifies a specific commit with a descriptive label.

What’s the difference between tags and branches? The workspace is (almost always) associated with a branch, called master by default. When it is, a commit will automatically update the master reference to point to that new commit; in other words, branches are mutable references.

A tag, on the other hand, is created to point to a specific commit and thereafter does not change, even if the branch moves on. In other words, tags are immutable references.

So I now made an annotated tag on each project:

$ go site
$ git tag -a v0.1.8 -m v0.1.8
$ git push origin v0.1.8

$ go north
$ git tag -a v0.1.7 -m v0.1.7
$ git push origin v0.1.7

$ go lino
$ git tag -a v1.6.13 -m v1.6.13
$ git push origin v1.6.13

$ go welfare
$ git tag -a v1.1.12 -m v1.1.12
$ git push origin v1.1.12

Each git push origin commands gave output similar to this:

$ git push origin v0.1.7
Counting objects: 1, done.
Writing objects: 100% (1/1), 160 bytes | 0 bytes/s, done.
Total 1 (delta 0), reused 0 (delta 0)
To git@github.com:lsaffre/north.git
 * [new tag]         v0.1.7 -> v0.1.7

The next step then was to increment the version numbers. Note the fab esi command. For example in Lino Welfare:

$ go welfare
$ fab esi

And change the file to:

SETUP_INFO = dict(
    name='lino-welfare',
    version='1.1.13',
    install_requires=['lino', 'suds', 'vobject', 'django-iban'],
    ...

Oops, then I noticed that I probably made a little mistake. Released versions should specify versions in their install_requires. So in fact before setting the tags I should have done something like:

SETUP_INFO = dict(
    name='lino-welfare',
    version='1.1.12',
    install_requires=['lino==1.6.12', 'suds', 'vobject', 'django-iban'],
    ...

And then, afterwards remove the version specificier (==1.6.12) again because it can be disturbing in development versions. Is that true?

If you use Git and followed until here, please tell me:

  • Did I get it right?

Another thing is to make this process more automatic. That’s for later.

Removed the “Export to .csv” button

I finally took the time to have a look at Joe’s work. This is really cool, Joe!

Since this “clone” works much better than the “original”, and since it is useless to have both, and since the original was not removable because still old-style coding, I simply removed the original.

This means that existing applications should include lino.modlib.export_excel to their lino.core.site.Site.get_installed_plugins() method.

I changed the action’s label from “To Excel” to “Export to .xls” because it doesn’t require any given proprietary produce, it works with every office application that can read .xls files.

I’d like to rename the app from “export_excel” to “export_xls” or maybe even simply “xls”. Any comments to this?