Add xapian database connection utilities.

* etc/default_settings.py (XAPIAN_DB_PATH): New variable.
* wqflask/wqflask/database.py: Import xapian.
(xapian_database, xapian_writable_database): New functions.

2 files changed, 21 insertions, 0 deletions

diff --git a/etc/default_settings.py b/etc/default_settings.py
index 6d7ac063..ab5a06cf 100644
--- a/etc/default_settings.py
+++ b/etc/default_settings.py
@@ -35,6 +35,8 @@ GN2_PROXY = "http://localhost:8080"
 
 # GN PROXY
 GN_PROXY_URL="https://genenetwork.org/gn3-proxy/"
+# Xapian index
+XAPIAN_DB_PATH = "xapian"
 
 # ---- MySQL
 
diff --git a/wqflask/wqflask/database.py b/wqflask/wqflask/database.py
index 505f4bd2..d392f1d1 100644
--- a/wqflask/wqflask/database.py
+++ b/wqflask/wqflask/database.py
@@ -8,6 +8,7 @@ import contextlib
 
 #: type: ignore
 import MySQLdb
+import xapian
 
 
 class Connection(Protocol):
@@ -65,3 +66,21 @@ def database_connection() -> Iterator[Connection]:
         connection.commit()
     finally:
         connection.close()
+
+
+@contextlib.contextmanager
+def xapian_database():
+    """Open xapian database read-only."""
+    # pylint: disable-next=invalid-name
+    db = xapian.Database(get_setting("XAPIAN_DB_PATH"))
+    yield db
+    db.close()
+
+
+@contextlib.contextmanager
+def xapian_writable_database():
+    """Open xapian database for writing."""
+    # pylint: disable-next=invalid-name
+    db = xapian.WritableDatabase(get_setting("XAPIAN_DB_PATH"))
+    yield db
+    db.close()