I am trying to execute a curl command within a python script.

If I do it in the terminal, it looks like this:

curl -X POST -d  '{"nw_src": "10.0.0.1/32", "nw_dst": "10.0.0.2/32", "nw_proto": "ICMP", "actions": "ALLOW", "priority": "10"}' http://localhost:8080/firewall/rules/0000000000000001

I've seen recommendations to use pycurl, but I couldn't figure out how to apply it to mine.

I tried using:

subprocess.call([
    'curl',
    '-X',
    'POST',
    '-d',
    flow_x,
    'http://localhost:8080/firewall/rules/0000000000000001'
])

and it works, but is there a better way?

You could use urllib as @roippi said:

import urllib2
data = '{"nw_src": "10.0.0.1/32", "nw_dst": "10.0.0.2/32", "nw_proto": "ICMP", "actions": "ALLOW", "priority": "10"}'
url = 'http://localhost:8080/firewall/rules/0000000000000001'
req = urllib2.Request(url, data, {'Content-Type': 'application/json'})
f = urllib2.urlopen(req)
for x in f:
    print(x)
f.close()

OJFord

Don't!

I know, that's the "answer" nobody wants. But if something's worth doing, it's worth doing right, right?

This seeming like a good idea probably stems from a fairly wide misconception that shell commands such as curl are anything other than programs themselves.

So what you're asking is "how do I run this other program, from within my program, just to make a measly little web request?". That's crazy, there's got to be a better way right?

Uxio's answer works, sure. But it hardly looks very Pythonic, does it? That's a lot of work just for one little request. Python's supposed to be about flying! Anyone writing that is probably wishing they just call'd curl!

it works, but is there a better way?

Yes, there is a better way!

Requests: HTTP for Humans

Things shouldn’t be this way. Not in Python.

Let's GET this page:

import requests
res = requests.get('https://stackoverflow.com/questions/26000336')

That's it, really! You then have the raw res.text, or res.json() output, the res.headers, etc.

You can see the docs (linked above) for details of setting all the options, since I imagine OP has moved on by now, and you - the reader now - likely need different ones.

But, for example, it's as simple as:

url     = 'http://example.tld'
payload = { 'key' : 'val' }
headers = {}
res = requests.post(url, data=payload, headers=headers)

You can even use a nice Python dict to supply the query string in a GET request with params={}.

Simple and elegant. Keep calm, and fly on.

If you are not tweaking the curl command too much you can also go and call the curl command directly

import shlex
cmd = '''curl -X POST -d  '{"nw_src": "10.0.0.1/32", "nw_dst": "10.0.0.2/32", "nw_proto": "ICMP", "actions": "ALLOW", "priority": "10"}' http://localhost:8080/firewall/rules/0000000000000001'''
args = shlex.split(cmd)
process = subprocess.Popen(args, shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
stdout, stderr = process.communicate()

Use this tool (hosted here for free) to convert your curl command to equivalent Python requests code:

Example: This,

curl 'https://www.example.com/' -H 'Connection: keep-alive' -H 'Cache-Control: max-age=0' -H 'Origin: https://www.example.com' -H 'Accept-Encoding: gzip, deflate, br' -H 'Cookie: SESSID=ABCDEF' --data-binary 'Pathfinder' --compressed

Gets converted neatly to:

import requests

cookies = {
    'SESSID': 'ABCDEF',
}

headers = {
    'Connection': 'keep-alive',
    'Cache-Control': 'max-age=0',
    'Origin': 'https://www.example.com',
    'Accept-Encoding': 'gzip, deflate, br',
}

data = 'Pathfinder'

response = requests.post('https://www.example.com/', headers=headers, cookies=cookies, data=data)

Rephrasing one of the answers in this post, instead of using cmd.split(). Try to use: