Pass variable to subprocess

Question

I am trying to construct a command which includes a a variable containing IP addresses to a subprocess but the variable is not passed.

iplist

8.8.8.8
1.1.1.1

code

with open('iplist', 'r', encoding="utf-8") as f:
    data = f.read()
    print(data)
    cmd = ['./mmdbinspect', '--db', '/usr/local/var/GeoIP/GeoLite2-City.mmdb', '$data']
    result = subprocess.run(cmd, stdout=subprocess.PIPE)
    print(result.stdout)

output

8.8.8.8
1.1.1.1
2020/11/01 10:06:13 could not get records from db /usr/local/var/GeoIP/GeoLite2-City.mmdb: $data is not a valid IP address
b''

f.read() will read entire file as one string so u need to use readlines() then iterate through those lines. — , Oct 31 '20 at 23:18
You don't want to pass `'$data'` to `subprocess.run`. If `data` is the string `'1.1.1.1'`, then you just want `data`. No dollar sign. No quotes. You want the contents of the variable `data` to be in the array. — Frank Yellin, Oct 31 '20 at 23:20
Your shell obviously has no idea what variables you have used in your Python program, any more than it knows what variable names are used in the C source files for Bash itself. — tripleee, Oct 12 '21 at 11:07

score 3 · Accepted Answer · edited Oct 31 '20 at 23:42

3

Something like

with open('iplist', 'r', encoding="utf-8") as ip_file:
    for ip in ip_file:
      cmd = ['./mmdbinspect', '--db', '/usr/local/var/GeoIP/GeoLite2-City.mmdb', ip.strip()]
      result = subprocess.run(cmd, stdout=subprocess.PIPE)
      print(result.stdout)

edited Oct 31 '20 at 23:42

ShadowRanger

143,180
12
188
271

answered Oct 31 '20 at 23:20

1

@zvi It's a mostly correct answer with an editorial mistake. Fixed. – cs95 Oct 31 '20 at 23:34

score 1 · Answer 2 · answered Oct 31 '20 at 23:21

1

Use: cmd = ['./mmdbinspect', '--db', '/usr/local/var/GeoIP/GeoLite2-City.mmdb', data]

data is a variable name.

$data is used on other languages (like PHP).

answered Oct 31 '20 at 23:21

zvi

3,677
2
30
48

score 1 · Answer 3 · answered Oct 31 '20 at 23:30

1

CYREX pointed me in right direction. Thank you.

Final code below

with open('iplist', 'r', encoding="utf-8") as f:
    data = f.readlines()
    print(data)
    for line in data:
        ip = line.strip() # strip \n lookup will fail
        cmd = ['./mmdbinspect', '--db', '/usr/local/var/GeoIP/GeoLite2-City.mmdb', ip]
        print(cmd)
        result = subprocess.run(cmd, stdout=subprocess.PIPE)
        print(result.stdout)

answered Oct 31 '20 at 23:30

pablo808

637
1
8
21

1

exactly, my code was missing the strip method, anyway, most important u solved it. regards. – Oct 31 '20 at 23:34

Pass variable to subprocess

3 Answers3

Linked