Sign in with http_options set will fail

[bcantoni]

Describe the bug
Signing in to a server when any http_options have been set in the TSC.Server object will result in an exception:

KeyError: 'X-TableauServerClient-Version'

Versions
TSC library versions v0.21 and v0.22 have the issue. Version v0.19.1 works correctly.

To Reproduce
Include any http_options while creating the TSC.Server object:

server = TSC.Server('https://10ax.online.tableau.com', use_server_version=True, http_options={"verify": False})
server.auth.sign_in(tableau_auth)

Workaround: use TSC v0.19.1 instead.

Results

Traceback (most recent call last):
  File "/Users/brian/github/server-client-python/pat-login.py", line 17, in <module>
    server = TSC.Server('https://10ax.online.tableau.com', use_server_version=True, http_options={"verify": False})
  File "/Users/brian/github/server-client-python/tableauserverclient/server/server.py", line 101, in __init__
    self.add_http_version_header()
  File "/Users/brian/github/server-client-python/tableauserverclient/server/server.py", line 112, in add_http_version_header
    if not self._http_options[client_version_header]:
KeyError: 'X-TableauServerClient-Version'

[t8y8]

https://github.com/tableau/server-client-python/pull/1075/files#diff-baff71702721406ed2f46c06b280ce8c2d463b77a5aa33badcb548d93ca31a7aR110 is the commit where it broke, I think you can just change it to...

def add_http_version_header(self):
    if client_version_header not in self._http_options:
        self._http_options[client_version_header] = __TSC_VERSION__

That's a slightly more idiomatic way to do a key check in a dict.

The following works too, if you want the smallest possible fix:

def add_http_version_header(self):
    if not self._http_options.get(client_version_header):
        self._http_options.update({client_version_header: __TSC_VERSION__})

It's probably better to put those module level constants as ALL_CAPS or _PREFIXED given they're not really useful outside this context

[bcantoni]

I tested with current development branch with Jac's fix merged and it looks correct now.

[bcantoni]

This is fixed now in release 0.23.