Accept Merge Request #32: (api -> master)

Merge Request: Add project ref count to allow multiple connections

Created By: @王琼钰
Accepted By: @王琼钰
URL: https://tjwater.coding.net/p/tjwatercloud/d/TJWaterServer/git/merge/32

api/__init__.py

@@ -4,6 +4,7 @@ from .project import copy_project
 
 from .change_set import ChangeSet
 
+from .operation import get_current_operation
 from .operation import execute_undo as undo
 from .operation import execute_redo as redo
 from .operation import have_snapshot, take_snapshot, pick_snapshot

api/operation.py

@@ -29,7 +29,7 @@ def _get_parents(name: str, id: int) -> list[int]:
             ids.append(int(cur.fetchone()['parent']))
     return ids
 
-def _get_current_operation(name: str) -> int:
+def get_current_operation(name: str) -> int:
     with conn[name].cursor(row_factory=dict_row) as cur:
         cur.execute(f"select id from current_operation")
         return int(cur.fetchone()['id'])
@@ -40,7 +40,7 @@ def _update_current_operation(name: str, old_id: int, id: int) -> None:
 
 def _add_redo_undo(name: str, redo: str, undo: str) -> int:
     with conn[name].cursor(row_factory=dict_row) as cur:
-        parent = _get_current_operation(name)
+        parent = get_current_operation(name)
         cur.execute(f"insert into operation (id, redo, undo, parent) values (default, '{redo}', '{undo}', {parent})")
         cur.execute("select max(id) from operation")
         return int(cur.fetchone()['max'])
@@ -73,11 +73,11 @@ def _execute(name: str, sql: str) -> None:
 
 def add_operation(name: str, redo: str, undo: str) -> None:
     curr = _add_redo_undo(name, redo, undo)
-    old = _get_current_operation(name)
+    old = get_current_operation(name)
     _update_current_operation(name, old, curr)
 
 def execute_undo(name: str, discard: bool = False) -> None:
-    curr = _get_current_operation(name)
+    curr = get_current_operation(name)
 
     # transaction control
     if have_transaction(name):
@@ -106,7 +106,7 @@ def execute_undo(name: str, discard: bool = False) -> None:
         _remove_operation(name, curr)
 
 def execute_redo(name: str) -> None:
-    curr = _get_current_operation(name)
+    curr = get_current_operation(name)
     redoChild = _query_redo_child(name, curr)
     if redoChild == None:
         print("nothing to redo!")
@@ -132,7 +132,7 @@ def take_snapshot(name: str, tag: str) -> None:
         print('Non empty tag is expected!')
         return
 
-    curr = _get_current_operation(name)
+    curr = get_current_operation(name)
 
     with conn[name].cursor() as cur:
         cur.execute(f"insert into snapshot_operation (id, tag) values ({curr}, '{tag}')")
@@ -146,7 +146,7 @@ def pick_snapshot(name: str, tag: str) -> None:
         print('No such snapshot!')
         return
 
-    curr = _get_current_operation(name)
+    curr = get_current_operation(name)
     curr_parents = _get_parents(name, curr)
 
     with conn[name].cursor(row_factory=dict_row) as cur:
@@ -192,7 +192,7 @@ def start_transaction(name: str, strict: bool = False) -> None:
         print("Only support single transaction now, please commit/abort current transaction!")
         return
 
-    curr = _get_current_operation(name)
+    curr = get_current_operation(name)
 
     with conn[name].cursor() as cur:
         cur.execute(f"insert into transaction_operation (id, strict) values ({curr}, {strict});")
@@ -211,7 +211,7 @@ def abort_transaction(name: str) -> None:
 
     tran = _get_current_transaction_id(name)
 
-    curr = _get_current_operation(name)
+    curr = get_current_operation(name)
     curr_parents = _get_parents(name, curr)
 
     for i in range(curr_parents.index(tran)):

api/project.py

@@ -3,6 +3,8 @@ from .connection import g_conn_dict as conn
 
 # no undo/redo
 
+_project_open_count: dict[str, int] = {}
+
 def have_project(name: str) -> bool:
     with pg.connect(conninfo="dbname=postgres host=127.0.0.1", autocommit=True) as conn:
         with conn.cursor() as cur:
@@ -23,11 +25,19 @@ def delete_project(name: str) -> None:
             cur.execute(f"drop database {name}")
 
 def open_project(name: str) -> None:
-    conn[name] = pg.connect(conninfo=f"dbname={name} host=127.0.0.1", autocommit=True)
+    if name not in _project_open_count:
+        conn[name] = pg.connect(conninfo=f"dbname={name} host=127.0.0.1", autocommit=True)
+        _project_open_count[name] = 0
+
+    _project_open_count[name] += 1
 
 def is_project_open(name: str) -> bool:
     return name in conn
 
 def close_project(name: str) -> None:
-    conn[name].close()
-    del conn[name]
+    if name in _project_open_count:
+        _project_open_count[name] -= 1
+        if _project_open_count[name] == 0:
+            conn[name].close()
+            del conn[name]
+            del _project_open_count[name]

script/sql/create/operation.sql

@@ -1,3 +1,5 @@
+CREATE TYPE API_OPERATION AS ENUM ('add', 'delete', 'update');
+
 CREATE TABLE OPERATION
 (
   ID SERIAL PRIMARY KEY
@@ -5,6 +7,11 @@ CREATE TABLE OPERATION
 , Undo TEXT NOT NULL
 , Parent INTEGER REFERENCES OPERATION(ID)
 , Redo_Child INTEGER REFERENCES OPERATION(ID)
+, Api TEXT NOT NULL
+, Api_Operation API_OPERATION NOT NULL
+, Api_Operation_Type TEXT NOT NULL
+, Api_Operation_Id TEXT NOT NULL -- VARCHAR(32)
+, Api_Operation_Property TEXT NOT NULL
 );
 
 INSERT INTO OPERATION (ID, Redo, Undo) VALUES (0, '', '');

tjnetwork.py

@@ -64,6 +64,9 @@ def copy_project(source: str, new: str) -> None:
 # operation
 ############################################################
 
+def get_current_operation(name: str) -> int:
+    return api.get_current_operation(name)
+
 def undo(name: str) -> None:
     return api.undo(name)