Python requests: URL base in Session

Question

When using a Session, it seems you need to provide the full URL each time, e.g.

session = requests.Session()
session.get(\'http://myserver/getstuff\')
sessio         


        

Answer 1

I don't see a built-in way to do this, but you can use wrapper functions to add the functionality you want:

from functools import wraps
import inspect
import requests
from requests.compat import urljoin

def _base_url(func, base):
    '''Decorator for adding a base URL to func's url parameter'''

    @wraps(func)
    def wrapper(*args, **kwargs):
        argname = 'url'
        argspec = inspect.getargspec(func)

        if argname in kwargs:
            kwargs[argname] = urljoin(base, kwargs[argname])
        else:
            # Find and replace url parameter in positional args. The argspec
            # includes self while args doesn't, so indexes have to be shifted
            # over one
            for i, name in enumerate(argspec[0]):
                if name == argname:
                    args = list(args)
                    args[i-1] = urljoin(base, args[i-1])
                    break

        return func(*args, **kwargs)
    return wrapper

def inject_base_url(func):
    '''Decorator for adding a base URL to all methods that take a url param'''

    @wraps(func)
    def wrapper(*args, **kwargs):
        argname = 'base_url'

        if argname in kwargs:
            obj = args[0]

            # Add base_url decorator to all methods that have a url parameter
            for name, method in inspect.getmembers(obj, inspect.ismethod):
                argspec = inspect.getargspec(method.__func__)

                if 'url' in argspec[0]:
                    setattr(obj, name, _base_url(method, kwargs[argname]))

            del kwargs[argname]

        return func(*args, **kwargs)
    return wrapper

# Wrap requests.Session.__init__ so it takes a base_url parameter
setattr(
    requests.Session,
    '__init__',
    inject_base_url(getattr(requests.Session, '__init__'))
)

Now you can specify a base URL when you construct a new requests.Session object:

s = requests.Session(base_url='http://stackoverflow.com')
s.get('questions')      # http://stackoverflow.com/questions
s.post('documentation') # http://stackoverflow.com/documentation

# With no base_url, you get the default behavior
s = requests.Session()
s.get('http://google.com')