A quick tip to debug segfaults in QGIS Server.
Sometimes is hard to debug segfaults appearing in QGIS Server when running in CGI mode. The classic approach is attaching a
gdb to the running process.
The problem is that there is not enough time to do it!
A simple plugin filter, can provide you the time you need to attach the debugger:
from qgis.server import *
from qgis.core import *
import os
class DelayFilter(QgsServerFilter):
def __init__(self, serverIface):
super(DelayFilter, self).__init__(serverIface)
def responseComplete(self):
request = self.serverInterface().requestHandler()
params = request.parameterMap()
if params.get('DELAY', ''):
QgsMessageLog.logMessage("PID: %s" % os.getpid())
import time
time.sleep(30)
Calling the server with DELAY=1 will wait for 30 seconds and print the current PID in the server logs.
This will give you enough time to fire gdb and attach it to the process.