def get_migrated_params(
wf_module: WfModule,
*,
module_zipfile: ModuleZipfile = None) -> Dict[str, Any]:
"""
Read `wf_module.params`, calling migrate_params() or using cache fields.
Call this within a `Workflow.cooperative_lock()`.
If migrate_params() was already called for this version of the module,
return the cached value. See `wf_module.cached_migrated_params`,
`wf_module.cached_migrated_params_module_version`.
Raise `ModuleError` if migration fails.
Raise `KeyError` if the module was deleted.
Raise `RuntimeError` (unrecoverable) if there is a problem loading or
executing the module. (Modules are validated before import, so this should
not happen.)
The result may be invalid. Call `validate()` to raise a `ValueError` to
detect that case.
TODO avoid holding the database lock whilst executing stuff on the kernel.
(This will involve auditing and modifying all callers to handle new error
cases.)
"""
if module_zipfile is None:
# raise KeyError
module_zipfile = MODULE_REGISTRY.latest(wf_module.module_id_name)
stale = (
module_zipfile.version == "develop"
# works if cached version (and thus cached _result_) is None
or (module_zipfile.get_param_schema_version() !=
wf_module.cached_migrated_params_module_version))
if not stale:
return wf_module.cached_migrated_params
else:
# raise ModuleError
params = invoke_migrate_params(module_zipfile, wf_module.params)
wf_module.cached_migrated_params = params
wf_module.cached_migrated_params_module_version = (
module_zipfile.get_param_schema_version())
try:
wf_module.save(update_fields=[
"cached_migrated_params",
"cached_migrated_params_module_version",
])
except ValueError:
# WfModule was deleted, so we get:
# "ValueError: Cannot force an update in save() with no primary key."
pass
return params
def get_migrated_params(wf_module: WfModule) -> Dict[str, Any]:
"""
Read `wf_module.params`, calling migrate_params() or using cache fields.
Call this within a `Workflow.cooperative_lock()`.
If migrate_params() was already called for this version of the module,
return the cached value. See `wf_module.cached_migrated_params`,
`wf_module.cached_migrated_params_module_version`.
Raise `ModuleError` if migration fails.
Return `{}` if the module was deleted.
The result may be invalid. Call `validate()` to raise a `ValueError` to
detect that case.
"""
module_version = wf_module.module_version
if module_version is None:
return {}
if module_version.source_version_hash == "develop":
stale = True
elif (
# works if cached version (and thus cached _result_) is None
module_version.param_schema_version !=
wf_module.cached_migrated_params_module_version):
stale = True
else:
stale = False
if not stale:
return wf_module.cached_migrated_params
else:
loaded_module = LoadedModule.for_module_version(module_version)
if loaded_module:
params = wf_module.params # the user-supplied params
params = loaded_module.migrate_params(params) # raises ModuleError
wf_module.cached_migrated_params = params
wf_module.cached_migrated_params_module_version = (
module_version.param_schema_version)
# Write to DB, like wf_module.save(fields=[...]), even if the
# WfModule was deleted in a race
WfModule.objects.filter(id=wf_module.id).update(
cached_migrated_params=wf_module.cached_migrated_params,
cached_migrated_params_module_version=(
wf_module.cached_migrated_params_module_version),
)
return params
else:
return {}
