server/tags: add JSON export

API.md

@@ -115,6 +115,12 @@ data.
 
     Searches for tags.
 
+    **Note**: independently, the server exports current tag list snapshots to
+    the data directory under `tags.json` name. Its purpose is to reduce the
+    trips frontend needs to make when doing autocompletion, and ease caching.
+    The data directory and its URL are controlled with `data_dir` and
+    `data_url` variables in server's configuration.
+
     **Anonymous tokens**
 
     Same as `name` token.

server/szurubooru/api/tag_api.py

@@ -48,6 +48,7 @@ class TagListApi(BaseApi):
             ctx.session, names, category, suggestions, implications)
         ctx.session.add(tag)
         ctx.session.commit()
+        tags.export_to_json(ctx.session)
         return {'tag': _serialize_tag(tag)}
 
 class TagDetailApi(BaseApi):
@@ -84,6 +85,7 @@ class TagDetailApi(BaseApi):
 
         tag.last_edit_time = datetime.datetime.now()
         ctx.session.commit()
+        tags.export_to_json(ctx.session)
         return {'tag': _serialize_tag(tag)}
 
     def delete(self, ctx, tag_name):
@@ -98,4 +100,5 @@ class TagDetailApi(BaseApi):
         auth.verify_privilege(ctx.user, 'tags:delete')
         ctx.session.delete(tag)
         ctx.session.commit()
+        tags.export_to_json(ctx.session)
         return {}

server/szurubooru/tests/api/test_tag_creating.py

@@ -1,6 +1,7 @@
 import datetime
+import os
 import pytest
-from szurubooru import api, db, errors
+from szurubooru import api, config, db, errors
 from szurubooru.util import misc, tags
 
 def get_tag(session, name):
@@ -15,8 +16,14 @@ def assert_relations(relations, expected_tag_names):
 
 @pytest.fixture
 def test_ctx(
-        session, config_injector, context_factory, user_factory, tag_factory):
+        tmpdir,
+        session,
+        config_injector,
+        context_factory,
+        user_factory,
+        tag_factory):
     config_injector({
+        'data_dir': str(tmpdir),
         'tag_categories': ['meta', 'character', 'copyright'],
         'tag_name_regex': '^[^!]*$',
         'ranks': ['anonymous', 'regular_user'],
@@ -58,6 +65,7 @@ def test_creating_simple_tags(test_ctx, fake_datetime):
     assert tag.post_count == 0
     assert_relations(tag.suggestions, [])
     assert_relations(tag.implications, [])
+    assert os.path.exists(os.path.join(config.config['data_dir'], 'tags.json'))
 
 def test_duplicating_names(test_ctx):
     result = test_ctx.api.post(

server/szurubooru/tests/api/test_tag_deleting.py

@@ -1,12 +1,19 @@
 import pytest
+import os
 from datetime import datetime
-from szurubooru import api, db, errors
+from szurubooru import api, config, db, errors
 from szurubooru.util import misc, tags
 
 @pytest.fixture
 def test_ctx(
-        session, config_injector, context_factory, tag_factory, user_factory):
+        tmpdir,
+        session,
+        config_injector,
+        context_factory,
+        tag_factory,
+        user_factory):
     config_injector({
+        'data_dir': str(tmpdir),
         'privileges': {
             'tags:delete': 'regular_user',
         },
@@ -29,6 +36,7 @@ def test_removing_tags(test_ctx):
         'tag')
     assert result == {}
     assert test_ctx.session.query(db.Tag).count() == 0
+    assert os.path.exists(os.path.join(config.config['data_dir'], 'tags.json'))
 
 def test_removing_tags_without_privileges(test_ctx):
     test_ctx.session.add(test_ctx.tag_factory(names=['tag']))

server/szurubooru/tests/api/test_tag_export.py

@@ -0,0 +1,42 @@
+import datetime
+import os
+import json
+from szurubooru import config, db
+from szurubooru.util import tags
+
+def test_export(tmpdir, session, config_injector, tag_factory):
+    config_injector({
+        'data_dir': str(tmpdir)
+    })
+    sug1 = tag_factory(names=['sug1'])
+    sug2 = tag_factory(names=['sug2'])
+    imp1 = tag_factory(names=['imp1'])
+    imp2 = tag_factory(names=['imp2'])
+    tag = tag_factory(names=['alias1', 'alias2'])
+    tag.post_count = 1
+    session.add_all([tag, sug1, sug2, imp1, imp2])
+    session.flush()
+    session.add_all([
+        db.TagSuggestion(tag.tag_id, sug1.tag_id),
+        db.TagSuggestion(tag.tag_id, sug2.tag_id),
+        db.TagImplication(tag.tag_id, imp1.tag_id),
+        db.TagImplication(tag.tag_id, imp2.tag_id),
+    ])
+    session.flush()
+
+    tags.export_to_json(session)
+    export_path = os.path.join(config.config['data_dir'], 'tags.json')
+    assert os.path.exists(export_path)
+    with open(export_path, 'r') as handle:
+        assert json.loads(handle.read()) == [
+            {
+                'names': ['alias1', 'alias2'],
+                'usages': 1,
+                'suggestions': ['sug1', 'sug2'],
+                'implications': ['imp1', 'imp2'],
+            },
+            {'names': ['sug1'], 'usages': 0},
+            {'names': ['sug2'], 'usages': 0},
+            {'names': ['imp1'], 'usages': 0},
+            {'names': ['imp2'], 'usages': 0},
+        ]

server/szurubooru/tests/api/test_tag_updating.py

@@ -1,6 +1,7 @@
 import datetime
+import os
 import pytest
-from szurubooru import api, db, errors
+from szurubooru import api, config, db, errors
 from szurubooru.util import misc, tags
 
 def get_tag(session, name):
@@ -15,8 +16,14 @@ def assert_relations(relations, expected_tag_names):
 
 @pytest.fixture
 def test_ctx(
-        session, config_injector, context_factory, user_factory, tag_factory):
+        tmpdir,
+        session,
+        config_injector,
+        context_factory,
+        user_factory,
+        tag_factory):
     config_injector({
+        'data_dir': str(tmpdir),
         'tag_categories': ['meta', 'character', 'copyright'],
         'tag_name_regex': '^[^!]*$',
         'ranks': ['anonymous', 'regular_user'],
@@ -66,6 +73,7 @@ def test_simple_updating(test_ctx, fake_datetime):
     assert tag.category == 'character'
     assert tag.suggestions == []
     assert tag.implications == []
+    assert os.path.exists(os.path.join(config.config['data_dir'], 'tags.json'))
 
 def test_trying_to_update_non_existing_tag(test_ctx):
     with pytest.raises(tags.TagNotFoundError):

server/szurubooru/util/tags.py

@@ -1,4 +1,6 @@
 import datetime
+import os
+import json
 import re
 import sqlalchemy
 from szurubooru import config, db, errors
@@ -25,6 +27,24 @@ def _lower_list(names):
 def _check_name_intersection(names1, names2):
     return len(set(_lower_list(names1)).intersection(_lower_list(names2))) > 0
 
+def export_to_json(session):
+    output = []
+    for tag in session.query(db.Tag).all():
+        item = {
+            'names': [tag_name.name for tag_name in tag.names],
+            'usages': tag.post_count
+        }
+        if len(tag.suggestions):
+            item['suggestions'] = \
+                [rel.child_tag.names[0].name for rel in tag.suggestions]
+        if len(tag.implications):
+            item['implications'] = \
+                [rel.child_tag.names[0].name for rel in tag.implications]
+        output.append(item)
+    export_path = os.path.join(config.config['data_dir'], 'tags.json')
+    with open(export_path, 'w') as handle:
+        handle.write(json.dumps(output, separators=(',', ':')))
+
 def get_by_name(session, name):
     return session.query(db.Tag) \
         .join(db.TagName) \