On 2018-11-18 14:59, srinivasan wrote:
Dear Python Experts Team,
As am newbie to python and learning python, working on embedded linux
platform, my intention is to delete all the SSID's before connecting my
Wi-Fi module to specific SSID., I am trying to parse command output using
the "subprocess" with wrapper "execute_cmd_output_string" written on
it described
as below, using the nmcli commands "*nmcli -t -f TYPE,UUID con" and "**"nmcli
connection delete uuid ".*
Could you please help me, what could be the bug in the below method "*def
wifi_disconnect_reconnect(self, ssid, pw):" *using the method
"execute_cmd_output_string" (in-turn uses "subprocess") which is failing to
give correct output of., UUID's for *"nmcli connection delete uuid "* ?
But which works fine with "commands.getstatusoutput" (res =
commands.getstatusoutput("nmcli -t -f TYPE,UUID con")), but I dont want to
include "commands.getstatusoutput" which costs me for including one more
python module in my rootfs
Typical output for "nmcli -t -f TYPE,UUID con"
~$ nmcli -t -f TYPE,UUID con
802-11-wireless:3f5011d4-5681-4fed-8dea-95dee790e9e2
802-11-wireless:bfb93be0-740d-426e-b215-0fdc2f652877
802-11-wireless:69b60cf4-65aa-442b-a54c-fb82905adb0d
802-11-wireless:dc2a15ec-d3da-491e-9c8f-cb054f375837
802-11-wireless:5164e7f2-4489-462e-b093-76bc51bf1303
802-11-wireless:d462e8c4-fac7-42f2-8f9a-6846f52d4e8c
802-11-wireless:e5020744-5c9c-453c-92ec-7a854fc893e6
802-11-wireless:eed3358e-8635-471d-b7e9-5c2973a05128
802-11-wireless:ceea6707-a929-4941-9047-a75e061914b6
802-11-wireless:dd6b9c83-db7b-42b9-99c0-14a04f6f35f5
802-11-wireless:9f764fff-6288-49c4-9412-902e89230136
802-11-wireless:72c627cd-77a3-4d16-bb2c-058040d8e4fc
~$
*Python Code Snipeet:*
*------------------------------*
* def wifi_disconnect_reconnect(self, ssid, pw):*
* """*
* Connect to Access point using SSID and PW.*
* :param ssid: SSID of the ACCESS POINT.*
* :param pw: password for connecting to the access point.*
* :return: command output as True or False.*
* """*
* cmd = "nmcli -t -f TYPE,UUID con"*
* res = self._helper.execute_cmd_output_string(cmd)*
* print(res)*
* lines = res[1].split('\n') ------------------------> I suspect the
issue might be here*
* print(lines)*
* for line in lines:*
* parts = line.split(":")*
* print(parts)*
* print(parts[1])*
* if (parts[0] == "802-11-wireless"):*
* print("nmcli connection delete uuid "+ parts[1])*
* os.system("nmcli connection delete uuid "+ parts[1])*
* cmd = "nmcli device wifi connect '%s' password %s" % (ssid, pw)*
* exit_code = self._helper.execute_cmd_return_code(cmd)*
* return True if exit_code == 0 else False*
def execute_cmd_output_string(self, cmd, enable_shell=False):
"""
Execute a command and return its output as a string.
:param cmd: abs path of the command with arguments
:param enable_shell : force the cmd to be run as shell script
:return: a string.
"""
try:
result = subprocess.check_output(split(cmd),
stderr=subprocess.STDOUT,
shell=enable_shell)
except subprocess.CalledProcessError as e:
s = """While executing '{}' something went wrong.
Return code == '{}'
Return output:\n'{}'
""".format(cmd, e.returncode, e.output, shell=enable_shell)
raise AssertionError(s)
return result.strip().decode("utf-8")
if __name__ == "__main__":
m = wifi()
print("disconnect and reconnect")
print(m.wifi_disconnect_reconnect("NaWiFi", "abcds"))
*Errors:*
-----------
Traceback (most recent call last):
802-11-wireless:3f5011d4-5681-4fed-8dea-95dee790e9e2
802-11-wireless:dc2a15ec-d3da-491e-9c8f-cb054f375837
802-11-wireless:5164e7f2-4489-462e-b093-76bc51bf1303
File
"/home/srinivasan/Downloads/qa_wifi_nov15_after_incorporating_thilo_comments_zip/qa/test_library/wifi.py",
line 153, in <module>
802-11-wireless:d462e8c4-fac7-42f2-8f9a-6846f52d4e8c
print(m.wifi_connect("NI WiFi", "T.f.o.s.1996!"))
802-11-wireless:e5020744-5c9c-453c-92ec-7a854fc893e6
802-11-wireless:eed3358e-8635-471d-b7e9-5c2973a05128
File
"/home/srinivasan/Downloads/qa_wifi_nov15_after_incorporating_thilo_comments_zip/qa/test_library/wifi.py",
line 77, in wifi_connect
802-11-wireless:ceea6707-a929-4941-9047-a75e061914b6
print(parts[1])
802-11-wireless:dd6b9c83-db7b-42b9-99c0-14a04f6f35f5
*IndexError: list index out of range*
802-11-wireless:9f764fff-6288-49c4-9412-902e89230136
802-11-wireless:72c627cd-77a3-4d16-bb2c-058040d8e4fc
[u'0']
[u'0']
[snip]
execute_cmd_output_string returns a string, so 'res' will be a string.
For example, res == u'802-11-wireless:3f5011d4-5681-4fed-8dea-95dee790e9e2'.
That means that res[1] == u'0'.
So res[1].split('\n') == [u'0'].
If you follow the code from there, so you'll see that it'll eventually
raise IndexError.
--
https://mail.python.org/mailman/listinfo/python-list
