KBEngine Module
The KBEngine module provides Python script control for the dbmgr process to handle entity login queries, data storage, and more.
Member Functions
def addTimer( initialOffset, repeatOffset=0, callbackObj=None ):
def delTimer( id ):
def executeRawDatabaseCommand( command, callback, threadID, dbInterfaceName ):
def urlopen( url, callback, postData, headers ):
Callback Functions
def onDBMgrReady( ):
def onDBMgrShutDown( ):
def onReadyForShutDown( ):
def onSelectAccountDBInterface( accountName ):
Member Function Documentation
def addTimer( initialOffset, repeatOffset=0, callbackObj=None ):
Description:
Registers a timer, which is triggered by the callback function callbackObj. The callback function will be executed for the first time after "initialOffset" seconds, and then every "repeatOffset" seconds.
Example:
# Example of using addTimer
import KBEngine
# Add a timer, execute for the first time after 5 seconds, then every 1 second, user parameter is 9
KBEngine.addTimer( 5, 1, onTimer_Callbackfun )
# Add a timer, execute after 1 second, user parameter defaults to 0
KBEngine.addTimer( 1, onTimer_Callbackfun )
def onTimer_Callbackfun( id ):
print("onTimer_Callbackfun called: id %i" % ( id ))
# if this is a repeating timer, when it is no longer needed, call the following function to remove it:
# KBEngine.delTimer( id )Parameters:
initialOffset: float, the interval (seconds) from registration to the first callback.
repeatOffset: float, the interval (seconds) between each execution after the first callback. Must be removed with delTimer, otherwise it will repeat indefinitely. Values less than or equal to 0 will be ignored.
callbackObj: function, the specified callback function object.
Returns:
integer, returns the internal id of the timer, which can be used to remove the timer with delTimer.
def delTimer( id ):
Description:
The delTimer function is used to remove a registered timer. The removed timer will no longer execute. Timers that only execute once are automatically removed after the callback, so there is no need to remove them with delTimer. If delTimer is called with an invalid id (e.g., already removed), an error will occur.
See KBEngine.addTimer for an example of using timers.
Parameters:
id: integer, specifies the timer id to remove.
def executeRawDatabaseCommand( command, callback, threadID, dbInterfaceName ):
Description:
This script function executes a raw database command on the database, which will be parsed directly by the relevant database.
Please note that modifying entity data with this function may not take effect, because if the entity has been checked out, the modified entity data will still be overwritten by the entity archive.
It is strongly discouraged to use this function to read or modify entity data.
Parameters:
command: This database command will vary depending on the database configuration. For MySQL, it is an SQL query statement.
callback: Optional parameter, a callback object (such as a function) with the result of the command execution. This callback takes 4 parameters: result set, affected rows, insert id, error message.
Example Declaration
def sqlcallback(result, rows, insertid, error):
print(result, rows, insertid, error)As shown above:
result corresponds to the "result set", which is a list of rows. Each row is a list of string field values.
If the command does not return a result set (e.g., DELETE command), or if there is an error, this result set is None.
rows is the "number of affected rows", an integer indicating the number of rows affected by the command. This parameter is only relevant for commands that do not return a result set (such as DELETE).
If there is a result set or an error, this parameter is None.
insertid is the "auto-increment value", similar to the entity's databaseID. When data is successfully inserted into a table with an auto-increment field, it returns the value assigned to the auto-increment field at insertion. For more information, see MySQL's mysql_insert_id() method. This parameter is only meaningful when the database type is MySQL.
error is the "error message". If there is an error, this parameter is a string describing the error. If there is no error, this parameter is None.
threadID: int32, optional parameter, specifies a thread to handle this command. You can use this parameter to control the execution order of certain commands (dbmgr is multi-threaded). By default, it is not specified. If threadID is the entity's ID, it will be added to the entity's archive queue and written sequentially by the thread.
dbInterfaceName: string, optional parameter, specifies which database interface to use, defaults to the "default" interface. Database interfaces are defined in kbengine_defaults.xml->dbmgr->databaseInterfaces.
def urlopen( url, callback, postData, headers ):
Description:
This script function provides asynchronous HTTP/HTTPS requests.
Parameters:
url: A valid HTTP/HTTPS URL, string type.
callback: Optional parameter, a callback object (such as a function) with the result of the request. This callback takes 5 parameters: HTTP response code (e.g., 200), response content, HTTP headers, success status, and the request URL.
Example Declaration:
def onHttpCallback(httpcode, data, headers, success, url):
print(httpcode, data, headers, success, url)As shown above:
httpcode: The HTTP response code, an integer value.
data: The response content, a string.
headers: The HTTP headers returned by the server, e.g., {"Content-Type": "application/x-www-form-urlencoded"}, a dictionary.
success: Whether the request was successful. If there was an error, this is False. You can use httpcode to further determine the error.
url: The URL used for the request.
postData: Optional parameter. By default, a GET request is made to the server. If you need a POST request, provide the content to POST, and the engine will automatically use POST. It is bytes.
headers: Optional parameter. The HTTP headers to use for the request, e.g., {"Content-Type": "application/x-www-form-urlencoded"}, a dictionary.
Callback Function Documentation
def onDBMgrReady( ):
Description:
This function is called when the current process is ready.
Note
This callback must be implemented in the entry module (kbengine_defaults.xml->entryScriptFile).
def onDBMgrShutDown( ):
Description:
This function is called when the process is shutting down.
Note
This callback must be implemented in the entry module (kbengine_defaults.xml->entryScriptFile).
def onReadyForShutDown( ):
Description:
If this function is implemented in the script, it will be called when the process is about to exit.
You can use this callback to control the timing of process exit.
Note
This callback must be implemented in the entry module (kbengine_defaults.xml->entryScriptFile).
Returns:
bool, if True is returned, the process is allowed to proceed with exit. If any other value is returned, the process will ask again after a while.
def onSelectAccountDBInterface( accountName ):
Description:
This callback returns the database interface corresponding to a certain account. After selecting the interface, dbmgr will perform all related operations for this account using the corresponding database interface.
Database interfaces are defined in kbengine_defaults.xml->dbmgr->databaseInterfaces.
With this interface, you can decide which database an account should be stored in based on accountName.
Note
This callback must be implemented in the entry module (kbengine_defaults.xml->entryScriptFile).
Parameters:
accountName: string, the name of the account.
Returns:
string, the name of the database interface (database interfaces are defined in kbengine_defaults.xml ->dbmgr->databaseInterfaces).