Fix bug - sometime ssh forwarding connection cannot establish when cpu is in hight...

diff --git a/board/suanzi-support b/board/suanzi-support
index f55b41a..8d398bd 100755 (executable)
--- a/board/suanzi-support
+++ b/board/suanzi-support
@@ -6,7 +6,7 @@ import shlex
 import random
 from uuid import getnode as get_mac
 import ast
-import sys
+import sys, os
 import re
 
 MQTT_SERVER = 'mqtt.suanzi.ai'
@@ -42,13 +42,44 @@ def get_mac_str():
 def get_hostname():
     return check_output("/bin/hostname", shell=True).strip();
 
+def check_ssh_connection(port):
+    command = '/bin/ps aux | /bin/grep -E \'ssh.*' + str(port) + '\' | /bin/grep -v grep | wc -l';
+    output = check_output(command, shell=True)
+    print 'output: ', output
+    if int(output) == 0:
+        return False
+    else:
+        return True
+
+def try_use_rsa():
+    pub = os.getenv('HOME') + "/.ssh/id_rsa.pub"
+    if not os.path.isfile(pub):
+        # generate id_rsa.pub
+        command = 'ssh-keygen -b 2048 -t rsa -f ~/.ssh/id_rsa -P ""'
+        print command
+        print call(command, shell=True)
+    # copy id_rsa.pub
+    command = 'sshpass -p' + PASSWORD + ' ssh-copy-id -o "StrictHostKeyChecking=no"  -o "UserKnownHostsFile /dev/null" ' + USER + '@' + SSH_SERVER
+    print command
+    print call(command, shell=True)
+
+
+
 def exec_ssh(port):
+    print "#### start establish ssh forwarding connection port, ", port
     if port == None:
         raise Exception('Port not avaliable')
     command = 'sshpass -p' + PASSWORD + ' ssh -o "StrictHostKeyChecking=no"  -o "UserKnownHostsFile /dev/null" -o "ServerAliveInterval 60" -o "ServerAliveCountMax 3" -fCR ' + str(port) +':localhost:22 ' + USER + '@' + SSH_SERVER + ' sleep ' + str(ALIVE_TIME)
     print command
-    return call(shlex.split(command), shell=False)
-
+    ret = call(shlex.split(command), shell=False)
+    if check_ssh_connection(port):
+        return ret
+    else: ## if sshpass fails (sometimes when another process has large CPU usage (100%) , no ssh connection, try another, 
+        try_use_rsa()
+        command = 'ssh -o "PasswordAuthentication=no" -o "StrictHostKeyChecking=no"  -o "UserKnownHostsFile /dev/null" -o "ServerAliveInterval 60" -o "ServerAliveCountMax 3" -fCR ' + str(port) +':localhost:22 ' + USER + '@' + SSH_SERVER + ' sleep ' + str(ALIVE_TIME)
+        print command
+        ret = call(shlex.split(command), shell=False)
+        return ret
 
 def on_connect(client, userdata, flags, rc):
     client.subscribe(userdata['id'])
@@ -63,6 +94,7 @@ def on_message(client, userdata, msg):
         if payload['command'] == 'ssh':
             port = getAvailablePort(SSH_SERVER, PORT_RANGE)
             if exec_ssh(port) == 0:
+                print "#### OK, SSH forwarding connection established, port, ", port
                 response = {'from': userdata['id'], 'type':'response', 'command':payload['command'], 'data':port}
                 client.publish(payload['from'], str(response))
             else: