Select an app version#

Goal#

Call a specific version of a PlayMolecule app, instead of the latest-by-default.

Minimal example#

from playmolecule.apps import proteinprepare

# Always whatever version is installed as latest
ed = proteinprepare(outdir="out", pdbid="3ptb")

# Pinned to v1
ed = proteinprepare.v1.proteinprepare(outdir="out", pdbid="3ptb")

Why#

The unqualified app symbol (proteinprepare) is an alias for the latest installed version. That’s convenient for exploration, but it means an update_apps() call can change your script’s behavior without your code changing. For anything reproducible (published results, CI pipelines, batch sweeps), call the version explicitly.

How versions are exposed#

When PlayMolecule discovers an app, it builds a submodule per version:

playmolecule.apps.<appname>             # alias for latest
playmolecule.apps.<appname>.v1          # explicit version 1
playmolecule.apps.<appname>.v2          # explicit version 2
...

Each version submodule exposes the same set of callable functions plus artifacts, datasets, files, and __manifest__. The tests namespace lives on each function (e.g. proteinprepare.v1.proteinprepare.tests), not on the submodule itself. Parameters and defaults can differ between versions, which is the whole point of versioning.

List versions installed#

import playmolecule.apps.proteinprepare as pp
[name for name in dir(pp) if name.startswith("v") and name[1:].isdigit()]

Or look at the qualified paths in describe_apps():

ProteinPrepare playmolecule.apps.proteinprepare.v1.proteinprepare
ProteinPrepare playmolecule.apps.proteinprepare.v2.proteinprepare

Compare versions before upgrading#

help(proteinprepare.v1.proteinprepare)
help(proteinprepare.v2.proteinprepare)

Each version’s function carries its own manifest-derived docstring, so help shows you exactly what differs between them before you upgrade.

Gotchas#

  • The “latest” alias is computed at import time by natural sort of version strings. v10 correctly sorts after v9.

  • Pinning to a version that isn’t installed raises AttributeError. Catch it explicitly if your script must run against installs of unknown vintage.

  • Pinning a version doesn’t pin the container image’s runtime dependencies, only the manifest contract. Image SHAs change when Acellera ships fixes; combine version pinning with update_apps() discipline for full reproducibility.

See also#