Tweak the ranking of PG user dir search

This commit is contained in:
Erik Johnston 2017-06-13 10:16:31 +01:00
parent a837765e8c
commit b58e24cc3c

View File

@ -391,11 +391,14 @@ class UserDirectoryStore(SQLBaseStore):
]
}
"""
search_query = _parse_query(self.database_engine, search_term)
if isinstance(self.database_engine, PostgresEngine):
full_query, exact_query, prefix_query = _parse_query_postgres(search_term)
# We order by rank and then if they have profile info
# The ranking algorithm is hand tweaked for "best" results. Broadly
# the idea is we give a higher weight to exact matches.
# The array of numbers are the weights for the various part of the
# search: (domain, _, display name, localpart)
sql = """
SELECT user_id, display_name, avatar_url
FROM user_directory_search
@ -403,13 +406,27 @@ class UserDirectoryStore(SQLBaseStore):
INNER JOIN users_in_pubic_room USING (user_id)
WHERE vector @@ to_tsquery('english', ?)
ORDER BY
ts_rank_cd(vector, to_tsquery('english', ?), 1) DESC,
2 * ts_rank_cd(
'{0.1, 0.1, 0.9, 1.0}',
vector,
to_tsquery('english', ?),
8
)
+ ts_rank_cd(
'{0.1, 0.1, 0.9, 1.0}',
vector,
to_tsquery('english', ?),
8
)
DESC,
display_name IS NULL,
avatar_url IS NULL
LIMIT ?
"""
args = (search_query, search_query, limit + 1,)
args = (full_query, exact_query, prefix_query, limit + 1,)
elif isinstance(self.database_engine, Sqlite3Engine):
search_query = _parse_query_sqlite(search_term)
sql = """
SELECT user_id, display_name, avatar_url
FROM user_directory_search
@ -439,7 +456,7 @@ class UserDirectoryStore(SQLBaseStore):
})
def _parse_query(database_engine, search_term):
def _parse_query_sqlite(search_term):
"""Takes a plain unicode string from the user and converts it into a form
that can be passed to database.
We use this so that we can add prefix matching, which isn't something
@ -451,11 +468,21 @@ def _parse_query(database_engine, search_term):
# Pull out the individual words, discarding any non-word characters.
results = re.findall(r"([\w\-]+)", search_term, re.UNICODE)
return " & ".join("(%s* | %s)" % (result, result,) for result in results)
if isinstance(database_engine, PostgresEngine):
return " & ".join("(%s:* | %s)" % (result, result,) for result in results)
elif isinstance(database_engine, Sqlite3Engine):
return " & ".join("(%s* | %s)" % (result, result,) for result in results)
else:
# This should be unreachable.
raise Exception("Unrecognized database engine")
def _parse_query_postgres(search_term):
"""Takes a plain unicode string from the user and converts it into a form
that can be passed to database.
We use this so that we can add prefix matching, which isn't something
that is supported by default.
"""
# Pull out the individual words, discarding any non-word characters.
results = re.findall(r"([\w\-]+)", search_term, re.UNICODE)
both = " & ".join("(%s:* | %s)" % (result, result,) for result in results)
exact = " & ".join("%s" % (result,) for result in results)
prefix = " & ".join("%s:*" % (result,) for result in results)
return both, exact, prefix