Use per-db state to properly handle transactions requested on a datab…

…ase that is being opened (#184).

Document related txLocks & openDBs map objects.

Mark other bugs to be fixed (#204/#209/#210).

SQLitePlugin.coffee.md

@@ -14,8 +14,19 @@
 
     READ_ONLY_REGEX = /^\s*(?:drop|delete|insert|update|create)\s/i
 
+    # per-db state
+    DB_STATE_INIT = "INIT"
+    DB_STATE_OPEN = "OPEN"
+
 ## global(s):
 
+    # per-db map of locking and queueing
+    # XXX NOTE: This is NOT cleaned up when a db is closed and/or deleted.
+    # If the record is simply removed when a db is closed or deleted,
+    # it will cause some test failures and may break large-scale
+    # applications that repeatedly open and close the database.
+    # [BUG #210] TODO: better to abort and clean up the pending transaction state.
+    # XXX TBD this will be renamed and include some more per-db state.
     txLocks = {}
 
 ## utility functions:
@@ -65,6 +76,8 @@
 
 ## SQLite plugin db-connection handle
 
+#### NOTE: there can be multipe SQLitePlugin db-connection handles per open db.
+
 #### SQLite plugin db connection handle object is defined by a constructor function and prototype member functions:
 
     SQLitePlugin = (openargs, openSuccess, openError) ->
@@ -95,17 +108,21 @@
       return
 
     SQLitePlugin::databaseFeatures = isSQLitePluginDatabase: true
+
+    # Keep track of state of open db connections
+    # XXX TBD this will be moved and renamed or
+    # combined with txLocks.
     SQLitePlugin::openDBs = {}
 
     SQLitePlugin::addTransaction = (t) ->
-
       if !txLocks[@dbname]
         txLocks[@dbname] = {
           queue: []
           inProgress: false
         }
       txLocks[@dbname].queue.push t
-      @startNextTransaction()
+      if @dbname of @openDBs && @openDBs[@dbname] isnt DB_STATE_INIT
+        @startNextTransaction()
       return
 
     SQLitePlugin::transaction = (fn, error, success) ->
@@ -129,25 +146,46 @@
 
       nextTick () ->
         txLock = txLocks[self.dbname]
-        if txLock.queue.length > 0 && !txLock.inProgress
+        if !txLock
+          # XXX TBD TODO (BUG #210/??): abort all pending transactions with error cb
+          return
+
+        else if txLock.queue.length > 0 && !txLock.inProgress
           txLock.inProgress = true
           txLock.queue.shift().start()
         return
+
       return
 
     SQLitePlugin::open = (success, error) ->
-      onSuccess = () => success this
-
       if @dbname of @openDBs
-        ###
-        for a re-open run onSuccess async so that the openDatabase return value
-        can be used in the success handler as an alternative to the handler's
-        db argument
-        ###
-        nextTick () -> onSuccess()
+        # for a re-open run the success cb async so that the openDatabase return value
+        # can be used in the success handler as an alternative to the handler's
+        # db argument
+        nextTick =>
+          success @
+          return
+
       else
-        @openDBs[@dbname] = true
-        cordova.exec onSuccess, error, "SQLitePlugin", "open", [ @openargs ]
+        opensuccesscb = =>
+          # NOTE: the db state is NOT stored (in @openDBs) if the db was closed or deleted.
+
+          # XXX TODO [BUG #210]:
+          #if !@openDBs[@dbname] then call open error cb, and abort pending tx if any
+
+          if @dbname of @openDBs
+            @openDBs[@dbname] = DB_STATE_OPEN
+          success @
+
+          txLock = txLocks[@dbname]
+          if !!txLock && txLock.queue.length > 0 && !txLock.inProgress
+            @startNextTransaction()
+          return
+
+        # store initial DB state:
+        @openDBs[@dbname] = DB_STATE_INIT
+
+        cordova.exec opensuccesscb, error, "SQLitePlugin", "open", [ @openargs ]
 
       return
 
@@ -157,8 +195,10 @@
           error newSQLError 'database cannot be closed while a transaction is in progress'
           return
 
+        # XXX [BUG #209] closing one db handle disables other handles to same db
         delete @openDBs[@dbname]
 
+        # XXX [BUG #210] TODO: when closing or deleting a db, abort any pending transactions (with error callback)
         cordova.exec success, error, "SQLitePlugin", "close", [ { path: @dbname } ]
 
       else
@@ -167,6 +207,9 @@
       return
 
     SQLitePlugin::executeSql = (statement, params, success, error) ->
+      # XXX TODO: better to capture the result, and report it once
+      # the transaction has completely finished.
+      # This would fix BUG #204 (cannot close db in db.executeSql() callback).
       mysuccess = (t, r) -> if !!success then success r
       myerror = (t, e) -> if !!error then error e
 
@@ -463,6 +506,7 @@
           dblocation = if !!first.location then dblocations[first.location] else null
           args.dblocation = dblocation || dblocations[0]
 
+        # XXX [BUG #210] TODO: when closing or deleting a db, abort any pending transactions (with error callback)
         delete SQLitePlugin::openDBs[args.path]
         cordova.exec success, error, "SQLitePlugin", "delete", [ args ]