read data from subprocess, but it's bad for shell scripts

scalpels/cli/actions/start.py

@@ -7,6 +7,7 @@ import json
 from scalpels.db import api as db_api
 import subprocess
 import time
+import signal
 
 def _parse_agents_from_args(config):
     parsed_agents = set()
@@ -32,8 +33,9 @@ def _parse_agents_from_file(config):
     return parsed_agents
 
 # TODO this map should be saved in a config file
+# TODO refar to pre/exec/post
 agents_map = {
-    "mysql": "",
+    "mysql": "bash /opt/stack/scalpels/scripts/mysql-live.sh",
     "rabbit": "",
     "traffic": "",
     "rpctraffic": "",
@@ -47,13 +49,15 @@ def run(config):
     for ag in agents:
         ag_exec = agents_map.get(ag)
         if ag_exec:
-            ag_p = subprocess.Popen(ag_exec, stdout=subprocess.PIPE)
+            ag_p = subprocess.Popen(ag_exec.split(), stdout=subprocess.PIPE)
             running_agents.append(ag_p)
-    time.sleep(15)
+    time.sleep(5)
     data = []
     for ag_p in running_agents:
-        stdout = ag_p.communicate()[0]
-        ag_p.terminate()
+        # shell scripts has depend child which can't be killed by subprocess' API
+        # it should be ag_p.kill()
+        os.system("pkill -P %s" % ag_p.pid)
+        stdout = ag_p.stdout.read()
         data.append(stdout)
     rets = []
     ret = db_api.result_create(data)

scripts/mysql-live.sh

@@ -11,7 +11,20 @@ log_switch_var=general_log
 log_file=/tmp/mysqllive.log
 old_log_file=`mysql -e "SELECT @@$log_file_var" | grep -v $log_file_var | grep -v '\-\-\-\-\-'`
 old_log_switch=`mysql -e "SELECT @@$log_switch_var" | grep -v $log_switch_var | grep -v '\-\-\-\-\-'`
-trap ':' INT
+
+reset () {
+    echo -------------------------------------
+    echo reset $log_file_var to $old_log_file
+    echo reset $log_switch_var to $old_log_switch
+    mysql -e "SET GLOBAL $log_switch_var = $old_log_switch;"
+    mysql -e "SET GLOBAL $log_file_var = '$old_log_file';"
+
+    echo remove $log_file
+    echo -------------------------------------
+    sudo rm $log_file
+}
+
+trap "reset" SIGINT SIGTERM
 
 echo -------------------------------------
 echo reserve $log_file_var: $log_file
@@ -21,8 +34,11 @@ echo -------------------------------------
 mysql -e "SET GLOBAL $log_file_var = '$log_file';"
 mysql -e "SET GLOBAL $log_switch_var = ON;"
 
+sleep 1
+sudo chmod +r $log_file
+
 # TODO use awk /reg/ statement instead
-sudo tailf $log_file | awk '{
+tailf $log_file | awk '{
 if ( $1 + 0 != $1 )
     # TODO cat this line on its above line
     print $0;
@@ -37,13 +53,3 @@ else
     { $1=$2=""; print $0; print ""}
 }
 '
-
-echo -------------------------------------
-echo reset $log_file_var to $old_log_file
-echo reset $log_switch_var to $old_log_switch
-mysql -e "SET GLOBAL $log_switch_var = $old_log_switch;"
-mysql -e "SET GLOBAL $log_file_var = '$old_log_file';"
-
-echo remove $log_file
-echo -------------------------------------
-sudo rm $log_file