4D applications can generate several log files that are useful for debugging or optimizing their execution. Logs are usually started or stopped using selectors of the SET DATABASE PARAMETER or WEB SET OPTION commands and are stored in the Logs folder of the database (see the Description of 4D files section).

Information logged needs to be analyzed to detect and fix issues. This section provides a comprehensive description of the following log files:

• 4DRequestsLog.txt
• 4DRequestsLog_ProcessInfo.txt
• HTTPDebugLog.txt
• 4DDebugLog.txt (standard and tabular)
• 4DDiagnosticLog.txt,
• 4DIMAPLog.txt, 4DPOP3Log.txt, and 4DSMTPLog.txt
• ORDA client requests log file

Note: When a log file can be generated either on 4D Server or on the remote client, the word "Server" is added to the server-side log file name, for example "4DRequestsLogServer.txt"

Log files share some fields so that you can establish a chronology and make connections between entries while debugging:

• sequence_number: this number is unique over all debug logs and is incremented for each new entry whatever the log file, so that you can know the exact sequence of the operations.
• connection_uuid: for any 4D process created on a 4D client that connects to a server, this connection UUID is logged on both server and client side. It allows you to easily identify the remote client that launched each process.

This log file records standard requests carried out by the 4D Server machine or the 4D remote machine that executed the command (excluding Web requests).

How to start this log:

• on the server:
  
   SET DATABASE PARAMETER(4D Server log recording;1) //server side
• on a client:
  
   SET DATABASE PARAMETER(Client Log Recording;1) //remote side

Note: This statement also starts the 4DRequestsLog_ProcessInfo.txt log file (see below).

Headers

This file starts with the following headers:

• Log Session Identifier
• Hostname of the server that hosts the application
• User Login Name: login on the OS of the user that ran the 4D application on the server.

Contents

For each request, the following fields are logged:

Request flow:

This log file records information on each process created on the 4D Server machine or the 4D remote machine that executed the command (excluding Web requests).

How to start this log:

• on the server:
  
   SET DATABASE PARAMETER(4D Server log recording;1) //server side
• on a client:
  
   SET DATABASE PARAMETER(Client Log Recording;1) //remote side

Note: This statement also starts the 4DRequestsLog.txt log file (see above).

Headers

This file starts with the following headers:

• Log Session Identifier
• Hostname of the server that hosts the application
• User Login Name: login on the OS of the user that ran the 4D application on the server.

Contents

For each process, the following fields are logged:

This log file records each HTTP request and each response in raw mode. Whole requests, including headers, are logged; optionally, body parts can be logged as well.

How to start this log:

The following fields are logged for both Request and Response:

This log file records each event occurring at the 4D programming level. Standard mode provides a basic view of events.

How to start this log:

The following fields are logged for each event:  

This log file records each event occurring at the 4D programming level in a tabbed, compact format that includes additional information (compared to the standard format).

How to start this log:

The following fields are logged for each event:  

This log file records many events related to the internal application operation and is human-readable. You can include custom information in this file using the LOG EVENT command.

How to start this log:

The following fields are logged for each event:

Depending on the event, various other fields can also be logged, such as task, socket, etc. 

These log files record each exchange between the 4D application and the mail server (SMTP, POP3, IMAP) that has been initiated by the following commands:

• SMTP -  SMTP New transporter 
• POP3 -  POP3 New transporter
• IMAP  -  IMAP New transporter   

The log files can be produced in two versions:

• a regular version:
  • named 4DSMTPLog.txt, 4DPOP3Log.txt, or 4DIMAPLog.txt
  • no attachments
  • uses an automatic circular file recycling each 10 MB
  • intended for usual debugging

To start this log:

• •  SET DATABASE PARAMETER(SMTP Log;1) //start SMTP log OR
 SET DATABASE PARAMETER(POP3 Log;1) //start POP3 log OR
 SET DATABASE PARAMETER(IMAP Log;1) //start IMAP log
    
     
  • 4D Server: Click on the Start Request and Debug Logs button in the Maintenance Page of the 4D Server administration window.
    This log path is returned by the Get 4D file command.

• an extended version: 
  • attachment(s) included
  • no automatic recycling
  • custom name
  • reserved for specific purposes

To start this log:

• •  $server:=New object
 ...
  //SMTP
 $server.logFile:="MySMTPAuthLog.txt"
 $transporter:=SMTP New transporter($server)
 
  // POP3
 $server.logFile:="MyPOP3AuthLog.txt"
 $transporter:=POP3 New transporter($server)
 
  //IMAP
 $server.logFile:="MyIMAPAuthLog.txt"
 $transporter:=IMAP New transporter($server)

Contents

For each request, the following fields are logged:

This log records each ORDA request sent from a remote machine. You can direct log information to memory or to a file on disk. The name and location of this log file are your choice.

How to start this log:

Note: If you want to use the unique sequence number in ORDA request log, you need to trigger it:

The following fields are logged for each request: