{ "mode": "perldoc", "parameter": "MongoDB::Monitoring", "section": "", "url": "https://www.chedong.com/phpMan.php/perldoc/MongoDB%3A%3AMonitoring/json", "generated": "2026-06-15T11:50:43Z", "sections": { "NAME": { "content": "MongoDB::Monitoring - Internal event monitoring API for instrumentation\n", "subsections": [] }, "VERSION": { "content": "version v2.2.2\n", "subsections": [] }, "DESCRIPTION": { "content": "The MongoDB::MongoClient takes an optional \"monitoringcallback\" attribute, which can be used to\nmonitor events that occur during the operation of the driver.\n\nThe API is very simple: given a code reference, a hashref for each event is passed to the code\nreference. Here is a simple example that just accumulates events in an array:\n\nour @events;\nmy $cb = sub { push @events, $[0] };\n\nMongoDB->connect( $uri, { monitoringcallback => $cb } );\n", "subsections": [] }, "EVENT TYPES": { "content": "Every event is a hash reference, with a \"type\" field indicating the type, e.g.\n\"commandstarted\". Each type is described below.\n", "subsections": [ { "name": "Command Monitoring", "content": "These events are fired for commands directly to the wire and the response.\n\ncommandstarted\nThis event is sent just before a command is put one the wire. It will be followed by either a\n\"commandsucceeded\" or \"commandfailed\" event.\n\nFields:\n\n* type: \"commandstarted\"\n\n* databaseName: the name of the database to which the command applies\n\n* commandName: the name of the command being executed; for legacy operations that don't use\ncommands, the driver will convert them to appear as if they are in command form.\n\n* command: a hash reference representing the full command to be sent\n\n* requestId: the request identifier sent to the server\n\n* connectionId: address and port of the destination server\n\ncommandsucceeded\nThis event is sent just after a command reply is received, but only if the database reply\ndocument contains a non-false \"ok\" field. NOTE: write errors will have \"ok:1\" even though they\nhave write errors; for writes, success indicates that the write attempt was valid, not that the\nwrite succeeded.\n\nFields:\n\n* type: \"commandsucceeded\"\n\n* commandName: the name of the command being executed\n\n* durationSecs: the elapsed time in seconds since the \"commandstarted\" event.\n\n* reply: a hash reference representing the full database reply\n\n* requestId: the request identifier sent to the server\n\n* connectionId: address and port of the destination server\n\ncommandfailed\nThis event is sent just after a command reply is received, but only if the database reply\ndocument contains a false \"ok\" field or if an exception occurred during send or receive\noperations.\n\nFields:\n\n* type: \"commandfailed\"\n\n* commandName: the name of the command being executed\n\n* durationSecs: the elapsed time in seconds since the \"commandstarted\" event.\n\n* failure: a string with a error message about the failure\n\n* evalerror: if an exception occurs, this contains the value of $@ when the exception was\ncaught\n\n* reply: a hash reference representing the full database reply or an empty hashref if the\nfailure is due to an exception\n\n* requestId: the request identifier sent to the server\n\n* connectionId: address and port of the destination server\n" }, { "name": "Server Discovery and Monitoring", "content": "These events are fired when servers and topology are amended.\n\nserveropeningevent\nThis event is sent when a new server is added to the topology.\n\nFields:\n\n* type: \"serveropeningevent\"\n\n* topologyId: The topology refaddr\n\n* address: address of the server\n\nserverclosedevent\nThis event is sent when a server is removed from the topology.\n\nFields:\n\n* type: \"serverclosedevent\"\n\n* topologyId: The topology refaddr\n\n* address: address of the server\n\nserverdescriptionchangedevent\nThis event is sent when the server description changes, but does not include changes to the RTT.\n\nFields:\n\n* type: \"serverdescriptionchangedevent\"\n\n* address: address of the server\n\n* topologyId: The topology refaddr\n\n* previousDescription: Server Description before the change\n\n* newDescription: Server Description after the change\n\ntopologyopeningevent\nThis event is sent when the topology is created.\n\nFields:\n\n* type: \"topologyopeningevent\"\n\n* topologyId: The topology refaddr\n\ntopologyclosedevent\nThis event is sent when the topology is closed.\n\nFields:\n\n* type: \"topologyclosedevent\"\n\n* topologyId: The topology refaddr\n\ntopologydescriptionchangedevent\nThis event is sent when the topology description changes.\n\nFields:\n\n* type: \"topologydescriptionchangedevent\"\n\n* topologyId: The topology refaddr\n\n* previousDescription: Topology Description before the change\n\n* newDescription: Topology Description after the change\n\nserverheartbeatstartedevent\nThis event is sent before the ismaster command is sent to the server.\n\nFields:\n\n* type: \"serverheartbeatstartedevent\"\n\n* connectionId: address of the link to connect to\n\nserverheartbeatsucceededevent\nThis event is sent after the reply from the ismaster command arrives from a successful reply.\n\nFields:\n\n* type: \"serverheartbeatsucceededevent\"\n\n* duration: time it took to send and receive a reply\n\n* reply: the ismaster command reply\n\n* connectionId: address of the server\n\nserverheartbeatfailedevent\nThis event is sent if there is a failure from the ismaster command, which returns an error\nstring of some sort.\n\nFields:\n\n* type: \"serverheartbeatfailedevent\"\n\n* duration: time it took to send and receive a reply\n\n* failure: Returns an error string of the failure\n\n* connectionId: address of the server\n" } ] }, "REDACTION": { "content": "Certain commands are considered sensitive. When any of the following commands are seen in\nmonitoring, the command body and database reply body are replaced with an empty document:\n\n* authenticate\n\n* saslStart\n\n* saslContinue\n\n* getnonce\n\n* createUser\n\n* updateUser\n\n* copydbgetnonce\n\n* copydbsaslstart\n", "subsections": [] }, "AUTHORS": { "content": "* David Golden \n\n* Rassi \n\n* Mike Friedman \n\n* Kristina Chodorow \n\n* Florian Ragwitz \n", "subsections": [] }, "COPYRIGHT AND LICENSE": { "content": "This software is Copyright (c) 2020 by MongoDB, Inc.\n\nThis is free software, licensed under:\n\nThe Apache License, Version 2.0, January 2004\n", "subsections": [] } }, "summary": "MongoDB::Monitoring - Internal event monitoring API for instrumentation", "flags": [], "examples": [], "see_also": [] }