1
|
|
|
"""Ensemble backend that combines results from multiple projects""" |
2
|
|
|
|
3
|
|
|
from __future__ import annotations |
4
|
|
|
|
5
|
|
|
from typing import TYPE_CHECKING, Any |
6
|
|
|
|
7
|
|
|
import annif.eval |
8
|
|
|
import annif.parallel |
9
|
|
|
import annif.util |
10
|
|
|
from annif.exception import NotSupportedException |
11
|
|
|
from annif.suggestion import SuggestionBatch |
12
|
|
|
|
13
|
|
|
from . import backend, hyperopt |
14
|
|
|
|
15
|
|
|
if TYPE_CHECKING: |
16
|
|
|
from datetime import datetime |
17
|
|
|
|
18
|
|
|
from optuna.study.study import Study |
19
|
|
|
from optuna.trial import Trial |
20
|
|
|
|
21
|
|
|
from annif.backend.hyperopt import HPRecommendation |
22
|
|
|
from annif.corpus.document import Document, DocumentCorpus |
23
|
|
|
|
24
|
|
|
|
25
|
|
|
class BaseEnsembleBackend(backend.AnnifBackend): |
26
|
|
|
"""Base class for ensemble backends""" |
27
|
|
|
|
28
|
|
|
def _get_sources_attribute(self, attr: str) -> list[bool | None]: |
29
|
|
|
params = self._get_backend_params(None) |
30
|
|
|
sources = annif.util.parse_sources(params["sources"]) |
31
|
|
|
return [ |
32
|
|
|
getattr(self.project.registry.get_project(project_id), attr) |
33
|
|
|
for project_id, _ in sources |
34
|
|
|
] |
35
|
|
|
|
36
|
|
|
def initialize(self, parallel: bool = False) -> None: |
37
|
|
|
# initialize all the source projects |
38
|
|
|
params = self._get_backend_params(None) |
39
|
|
|
for project_id, _ in annif.util.parse_sources(params["sources"]): |
40
|
|
|
project = self.project.registry.get_project(project_id) |
41
|
|
|
project.initialize(parallel) |
42
|
|
|
|
43
|
|
|
def _suggest_with_sources( |
44
|
|
|
self, documents: list[Document], sources: list[tuple[str, float]] |
45
|
|
|
) -> dict[str, SuggestionBatch]: |
46
|
|
|
return { |
47
|
|
|
project_id: self.project.registry.get_project(project_id).suggest(documents) |
48
|
|
|
for project_id, _ in sources |
49
|
|
|
} |
50
|
|
|
|
51
|
|
|
def _merge_source_batches( |
52
|
|
|
self, |
53
|
|
|
batch_by_source: dict[str, SuggestionBatch], |
54
|
|
|
sources: list[tuple[str, float]], |
55
|
|
|
params: dict[str, Any], |
56
|
|
|
) -> SuggestionBatch: |
57
|
|
|
"""Merge the given SuggestionBatches from each source into a single |
58
|
|
|
SuggestionBatch. The default implementation computes a weighted |
59
|
|
|
average based on the weights given in the sources tuple. Intended |
60
|
|
|
to be overridden in subclasses.""" |
61
|
|
|
|
62
|
|
|
batches = [batch_by_source[project_id] for project_id, _ in sources] |
63
|
|
|
weights = [weight for _, weight in sources] |
64
|
|
|
return SuggestionBatch.from_averaged(batches, weights).filter( |
65
|
|
|
limit=int(params["limit"]) |
66
|
|
|
) |
67
|
|
|
|
68
|
|
|
def _suggest_batch( |
69
|
|
|
self, documents: list[Document], params: dict[str, Any] |
70
|
|
|
) -> SuggestionBatch: |
71
|
|
|
sources = annif.util.parse_sources(params["sources"]) |
72
|
|
|
batch_by_source = self._suggest_with_sources(documents, sources) |
73
|
|
|
return self._merge_source_batches(batch_by_source, sources, params) |
74
|
|
|
|
75
|
|
|
|
76
|
|
|
class EnsembleHPObjective(hyperopt.HPObjective): |
77
|
|
|
"""Objective function of the ensemble hyperparameter optimizer""" |
78
|
|
|
|
79
|
|
|
@classmethod |
80
|
|
|
def objective(cls, trial: Trial, args) -> float: |
81
|
|
|
eval_batch = annif.eval.EvaluationBatch(args["subject_index"]) |
82
|
|
|
proj_weights = { |
83
|
|
|
project_id: trial.suggest_float(project_id, 0.0, 1.0) |
84
|
|
|
for project_id in args["sources"] |
85
|
|
|
} |
86
|
|
|
for gold_batch, src_batches in zip( |
87
|
|
|
args["gold_batches"], args["source_batches"] |
88
|
|
|
): |
89
|
|
|
batches = [src_batches[project_id] for project_id in args["sources"]] |
90
|
|
|
weights = [proj_weights[project_id] for project_id in args["sources"]] |
91
|
|
|
avg_batch = SuggestionBatch.from_averaged(batches, weights).filter( |
92
|
|
|
limit=int(args["limit"]) |
93
|
|
|
) |
94
|
|
|
eval_batch.evaluate_many(avg_batch, gold_batch) |
95
|
|
|
results = eval_batch.results(metrics=[args["metric"]]) |
96
|
|
|
return results[args["metric"]] |
97
|
|
|
|
98
|
|
|
|
99
|
|
|
class EnsembleOptimizer(hyperopt.HyperparameterOptimizer): |
100
|
|
|
"""Hyperparameter optimizer for the ensemble backend""" |
101
|
|
|
|
102
|
|
|
def __init__( |
103
|
|
|
self, backend: EnsembleBackend, corpus: DocumentCorpus, metric: str |
104
|
|
|
) -> None: |
105
|
|
|
super().__init__(backend, corpus, metric, EnsembleHPObjective) |
106
|
|
|
self._sources = [ |
107
|
|
|
project_id |
108
|
|
|
for project_id, _ in annif.util.parse_sources( |
109
|
|
|
backend.config_params["sources"] |
110
|
|
|
) |
111
|
|
|
] |
112
|
|
|
|
113
|
|
|
def _prepare(self, n_jobs: int = 1) -> dict[str, Any]: |
114
|
|
|
gold_batches = [] |
115
|
|
|
source_batches = [] |
116
|
|
|
|
117
|
|
|
for project_id in self._sources: |
118
|
|
|
project = self._backend.project.registry.get_project(project_id) |
119
|
|
|
project.initialize() |
120
|
|
|
|
121
|
|
|
psmap = annif.parallel.ProjectSuggestMap( |
122
|
|
|
self._backend.project.registry, |
123
|
|
|
self._sources, |
124
|
|
|
backend_params=None, |
125
|
|
|
limit=int(self._backend.params["limit"]), |
126
|
|
|
threshold=0.0, |
127
|
|
|
) |
128
|
|
|
|
129
|
|
|
jobs, pool_class = annif.parallel.get_pool(n_jobs) |
130
|
|
|
|
131
|
|
|
with pool_class(jobs) as pool: |
132
|
|
|
for suggestions, gold_batch in pool.imap_unordered( |
133
|
|
|
psmap.suggest_batch, self._corpus.doc_batches |
134
|
|
|
): |
135
|
|
|
source_batches.append(suggestions) |
136
|
|
|
gold_batches.append(gold_batch) |
137
|
|
|
|
138
|
|
|
return { |
139
|
|
|
"gold_batches": gold_batches, |
140
|
|
|
"source_batches": source_batches, |
141
|
|
|
"subject_index": self._backend.project.subjects, |
142
|
|
|
"sources": self._sources, |
143
|
|
|
"limit": self._backend.params["limit"], |
144
|
|
|
"metric": self._metric, |
145
|
|
|
} |
146
|
|
|
|
147
|
|
|
def _normalize(self, hps: dict[str, float]) -> dict[str, float]: |
148
|
|
|
total = sum(hps.values()) |
149
|
|
|
return {source: hps[source] / total for source in hps} |
150
|
|
|
|
151
|
|
|
def _format_cfg_line(self, hps: dict[str, float]) -> str: |
152
|
|
|
return "sources=" + ",".join( |
153
|
|
|
[f"{src}:{weight:.4f}" for src, weight in hps.items()] |
154
|
|
|
) |
155
|
|
|
|
156
|
|
|
def _postprocess(self, study: Study) -> HPRecommendation: |
157
|
|
|
line = self._format_cfg_line(self._normalize(study.best_params)) |
158
|
|
|
return hyperopt.HPRecommendation(lines=[line], score=study.best_value) |
159
|
|
|
|
160
|
|
|
|
161
|
|
|
class EnsembleBackend(BaseEnsembleBackend, hyperopt.AnnifHyperoptBackend): |
162
|
|
|
"""Ensemble backend that combines results from multiple projects""" |
163
|
|
|
|
164
|
|
|
name = "ensemble" |
165
|
|
|
|
166
|
|
|
@property |
167
|
|
|
def is_trained(self) -> bool: |
168
|
|
|
sources_trained = self._get_sources_attribute("is_trained") |
169
|
|
|
return all(sources_trained) |
170
|
|
|
|
171
|
|
|
@property |
172
|
|
|
def modification_time(self) -> datetime | None: |
173
|
|
|
mtimes = self._get_sources_attribute("modification_time") |
174
|
|
|
return max(filter(None, mtimes), default=None) |
175
|
|
|
|
176
|
|
|
def get_hp_optimizer( |
177
|
|
|
self, corpus: DocumentCorpus, metric: str |
178
|
|
|
) -> EnsembleOptimizer: |
179
|
|
|
return EnsembleOptimizer(self, corpus, metric) |
180
|
|
|
|
181
|
|
|
def _train(self, corpus: DocumentCorpus, params: dict[str, Any], jobs: int = 0): |
182
|
|
|
raise NotSupportedException("Training ensemble backend is not possible.") |
183
|
|
|
|