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Revision as of 15:30, 17 November 2011 by Nsoranzo (talk | contribs) (Upgrade path constraint is formalized in the added link)

Upgradepath is a constraint that ensures the ability to upgrade from Fedora release N to Fedora release N+1.

In other words no package dependencies may break when the user wants to upgrade his/her Fedora. That is achieved by requiring the higher Fedora release to contain at least the same or higher package build versions (in N-V-R sense) than the lower Fedora release.

AutoQA executes this test for any update that is proposed in Bodhi and reports the result using Bodhi comments at the update page.

Does not apply for updates-testing
Upgradepath constraint is currently checked for main and stable updates repositories. It is not checked for updates-testing repository.

Understanding failures

This is a sample output of the upgradepath test, where duplicity-0.6.14-1.fc14 was requested to be pushed to dist-f14-updates repository:

============================================================
duplicity-0.6.14-1.fc14 into dist-f14-updates
============================================================
[ OK ] dist-f14
	Latest package: duplicity-0.6.09-1.fc14.1
[INFO] dist-f15 + dist-f15-updates 
	Latest package: duplicity-0.6.11-2.fc15
	Latest pending package: duplicity-0.6.14-1.fc15
	The pending package must be pushed together with the tested package, or else the upgrade path will be broken. 
[FAIL] f16 + f16-updates
	Latest package: duplicity-0.6.11-2.fc16
	Latest pending package: None
[ OK ] f17
	Latest package: duplicity-0.7.0-1.fc17
	Latest pending package: None
RESULT: FAILED

The OK sections denote repositories where upgradepath constraint would be fulfilled after pushing the proposed update. For example it would be possible to upgrade from dist-f14, because it contains lower version of duplicity package. And it would be also possible to (directly) upgrade to f17 repository, because it contains higher version of duplicity package.

The INFO section is almost the same as OK, it just means we provided some information you should read. In this case the upgradepath constraint will be fulfilled only if the build proposed for dist-f15-updates is pushed at the same time as our proposed build for dist-f14-updates. This happens quite often, because package maintainers use to propose new package builds for several Fedora releases at once. It is good to know though that if you notice that these pending builds were not pushed simultaneously you should contact RelEng team and ask them to fix it, otherwise your package will have its upgrade path broken.

If you look closely at the FAIL section, you'll see, that the union of f16 and f16-updates repositories contains only duplicity-0.6.11-2.fc16, which is lower version than currently proposed duplicity-0.6.14-1.fc14 for dist-f14-updates. It fails because you wouldn't be able upgrade from F14 (through F15) to F16 correctly if the proposed update had been pushed.

Upgradepath test algorithm

The formal description of the algorithm AutoQA uses for checking upgradepath constraint is here:

== Pushing to main repository ==
Pushing PKG to F(N)-main means:
  1. PKG in F(lower)-main <= PKG to push
  2. PKG in F(higher)-main >= PKG to push

== Pushing to updates repository ==
Pushing PKG to F(N)-updates means:
  1. PKG in F(lower)-main <= PKG to push
  2. PKG in F(lower)-updates <= PKG to push
  3. PKG in F(higher)-main union F(higher)-updates union F(higher)-updates-pending => PKG to push

Note: If PKG doesn't exist in REPO, it also satisfies any condition

Fixing the failures

The general guidelines for resolving failures include:

  1. Consult packaging guidelines when in doubt how package build versions are compared.
    See especially the Naming guidelines.
  2. Be conservative about karma auto-push when doing update for multiple releases.
    If you enable karma auto-push for a proposed update for several Fedora releases, it can easily happen that a lower-Fedora-release update will be auto-pushed sooner than a higher-Fedora-release update. Then you will receive failures from upgradepath. The best approach is to enable karma auto-push just for the highest Fedora release and handle the rest manually (push lower release update only after a higher release updates are pushed/requested).
  3. If you want to push a fix for an older Fedora but not for a newer one, do a proper minor release bump.
    Read Minor release bumps for old branches to learn more.

Further help

If you still don't understand why your update failed the test, or if you think there's something wrong in our test or its documentation, or if you have any other suggestions, please contact us.