An earlier change (due to @pedros) added the ability for plugins to define
template fields that work with Albums as well as Items. This enables some
cool new use cases but required that every template field definition check the
type of its arguments. Instead, this iteration on the idea distinguishes
between fields meant for Items and those meant for Albums.
In addition to simplifying the implementation of these functions, this also
enables the creation of album fields with identical names to item fields.
(For example, a user contacted me recently about adding a $bitrate field for
albums, which would be the average bitrate of the items. They can do this now
using a plugin.)
I also changed the docs to stop using the decorator approach to registering
template fields. We're moving toward removing those.
This is a refactor of the plugin developed by `imenem`.
- Pass `artist`, `album` and `va_likely` to `candidates()` so that
plugins don't have to work this out from `items` all over again.
- Pass `artist` and `title` to `item_candidates()`.
- Silence spurious `urllib3` info log lines.
- Use a proper "beets" user agent with `discogs_client`.
- Remove `abstract_search` plugin. It seems unnecessary. How many
music databases are there? How many will beets support? How much
common code might there be between them? We can add some abstraction
if or when more databases are supported.
- Derive more AlbumInfo and TrackInfo properties from discogs Release
objects, especially album ID so that beets doesn't just use the first
release and think all subsequent releases are duplicates.
- Add basic documentation, doc strings and code comments.
- Sanitise search query. Remove non-word characters and medium info that
might filter out good search results.
- Use artist `join` strings from discogs Release object when an album
or track has multiple artists.
- Don't rely on discogs track position, which is unreliable. But tracks
are in order, so we can recalculate medium and medium_index as long as
we can extract a consistent medium across tracks from the position.
- Add "various" as a known signal to indicate various artists.
- Prevent `chroma` plugin from returning a a huge track distance for any
track that is missing an ID (e.g. all discog tracks).
- `TrackInfo.index` should be the release index (calculated by beets),
not the medium index (derived from discogs track position).
- Add `AlbumInfo.data_source`. It's "Unknown" by default which is shown
in red when displaying a suggested or selected match. The built in
auto tagger sets it to "MusicBrainz" which is shown in green. Anything
else (e.g. "Discogs") is shown in yellow.
- Remove double spaces from album titles (bad data from Discogs).
- adds another traversal through all plugins' template_fields for each
'evaluate_template' call.
- requires the following idiom (or equivalent):
@Plugin.template_field(field')
def _tmpl_field(album):
"""Return stuff.
"""
if isinstance(album, Album):
return stuff
The initial idea for this refactor was motivated by the need to make
PluginQuery.match() have the same method signature as the match() methods on
other queries. That is, it needed to take an *item*, not the pattern and
value. (The pattern is supplied when the query is constructed.) So it made
sense to move the value-to-pattern code to a class method.
But then I realized that all the other FieldQuery subclasses needed to do
essentially the same thing. So I eliminated PluginQuery altogether and
refactored FieldQuery to subsume its functionality. I then changed all the
other FieldQuery subclasses to conform to the same pattern.
This has the side effect of allowing different kinds of queries (even
non-field queries) down the road.
In an attempt to finally address the longstanding SQLite locking issues, I'm
introducing a way to explicitly, lexically scope transactions. The Transaction
class is a context manager that always fully fetches after SELECTs and
automatically commits on exit. No direct access to the library is allowed, so
all changes will eventually be committed and all queries will be completed. This
will also provide a debugging mechanism to show where concurrent transactions
are beginning and ending.
To support composition (transaction reentrancy), an internal, per-Library stack
of transactions is maintained. Commits only happen when the outermost
transaction exits. This means that, while it's possible to introduce atomicity
bugs by invoking Library methods outside of a transaction, you can conveniently
call them *without* a currently-active transaction to get a single atomic
action.
Note that this "transaction stack" concepts assumes a single Library object per
thread. Because we need to duplicate Library objects for concurrent access due
to sqlite3 limitation already, this is fine for now. Later, the interface should
provide one transaction stack per thread for shared Library objects.
This is accomplished via a new event, "import_task_apply", which is called
right after metadata is applied to newly-imported items.
This change makes chroma REQUIRE a new version (0.6) of pyacoustid. Users with
older versions installed will see complaints about a missing method
"fingerprint_file".
The old "caching"-based approach to fingerprinting was kinda hacky to begin
with. Now, the chroma plugin has an explicit opportunity (in the form of a new
event) to perform its initial fingerprinting and lookup for all tracks. Then,
this information is used explicitly during the autotagging phase rather than
being used transparently through memoization of the lookup function.
