buendia-migrate can cause upgrades to wedge forever

[schuyler]

On a system that has buendia-db 0.16.2+b1118 installed, I foolishly ran apt-get upgrade which attempted to upgrade the package to 0.17+b1320, but this fails with:

/usr/bin/buendia-db-migrate: Attempting to migrate from 0.16 to 0.17
/usr/bin/buendia-db-migrate: Don't know how to migrate from version 0.16.2+b1118 to version 0.17+b1320.

At this point, running apt-get remove buendia-db yields

Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies:
 buendia-server : Depends: buendia-db (= 0.17+b1320) but it is not going to be installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).

Running sudo apt-get -f install yields:

Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
The following additional packages will be installed:
  buendia-db
The following packages will be upgraded:
  buendia-db
1 upgraded, 0 newly installed, 0 to remove and 13 not upgraded.
2 not fully installed or removed.
Need to get 0 B/1,094 B of archives.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n]
Reading changelogs... Done
(Reading database ... 58069 files and directories currently installed.)
Preparing to unpack .../buendia-db_0.17+b1320_all.deb ...
/usr/bin/buendia-db-migrate: Attempting to migrate from 0.16 to 0.17
/usr/bin/buendia-db-migrate: Don't know how to migrate from version 0.16.2+b1118 to version 0.17+b1320.
dpkg: error processing archive /var/cache/apt/archives/buendia-db_0.17+b1320_all.deb (--unpack):
 subprocess new pre-installation script returned error exit status 1
Errors were encountered while processing:
 /var/cache/apt/archives/buendia-db_0.17+b1320_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

Even with UPDATE_DESTRUCTIVE_UPGRADE enabled in the site settings, running buendia-update still yields:

--- Fixing up partially installed packages
dpkg: dependency problems prevent configuration of buendia-server:
 buendia-server depends on buendia-db (= 0.17+b1320); however:
  Version of buendia-db on system is 0.16.2+b1118.

dpkg: error processing package buendia-server (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of buendia-dashboard:
 buendia-dashboard depends on buendia-server; however:
  Package buendia-server is not configured yet.

dpkg: error processing package buendia-dashboard (--configure):
 dependency problems - leaving unconfigured
Errors were encountered while processing:
 buendia-server
 buendia-dashboard

and then

Preparing to unpack .../buendia-db_0.17+b1320_all.deb ...
/usr/bin/buendia-db-migrate: Attempting to migrate from 0.16 to 0.17
/usr/bin/buendia-db-migrate: Don't know how to migrate from version 0.16.2+b1118 to version 0.17+b1320.
dpkg: error processing archive /var/cache/apt/archives/buendia-db_0.17+b1320_all.deb (--unpack):
 subprocess new pre-installation script returned error exit status 1
Errors were encountered while processing:
 /var/cache/apt/archives/buendia-db_0.17+b1320_all.deb

Followed by

--- Attempting database migration
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies:
 buendia-server : Depends: buendia-db (= 0.17+b1320) but 0.16.2+b1118 is to be installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).

I submit that something is still messed up with our upgrade process if this state is possible to arrive at and impossible to leave without completely reinstalling the system.

[schuyler]

#216 was intended to fix this