post and authenticate to ghost

post_to_ghost.py

# Posts to Ghost via its API, given a piece of Markdown
# Markdown attachments are not yet supported
# (i.e: images must be linked to, not added inline)

# Import dependencies
import urllib2
import json

# Global constants
BASE_API_URL = 'https://joe.fo/ghost/api/v0.1'
CLIENT_ID = 'ghost-admin' # testing - pretend to be the ghost web-client
USER_AGENT = 'joefo/ghostclient'

# There are a few steps in order to post to Ghost:
# Step 1: Authenticate yourself
#
# Authentication is acheived using OAuth.
# You are required to send a POST request to
# BASE_API_URL/authentication/token

# From the docs at
# https://github.com/TryGhost/Ghost/wiki/How-does-oAuth-work-with-Ghost%3F

# POST BASE_API_URL/authentication/token
# Content-Type: application/x-www-form-urlencoded
# grant_type=password&username=<username>&password=<password>\
# &client_id=ghost-admin
# (no line-break)

# where <username> actually refers to the users' email address.

def get_oauth_token(username, password, url):
    """Requests a new OAuth token from a given URL.
    Faliures return None.

    This will return:
        a) None - if wrong username, password, or if
            no username / password / url was supplied
        b) A Dictionary (from a JSON object returned
            by the server, where json_object['access_token']
            is the OAuth token
        c) An error in various cases.
    """
    
    if not (username and password and url):
        # we need all of these things, so just return None
        # there is no way of authenticating with missing info.
        print('[OAuth]: username or password or url was missing')
        return None
    
    headers = {
        'Content-Type': 'application/x-www-form-urlencoded',
        'User-Agent': USER_AGENT
        }
    data = 'grant_type=password&username=' + username + \
           '&password=' + password + '&client_id=' + CLIENT_ID
    request = urllib2.Request(url, data=data, headers=headers)
    
    try:
        response = urllib2.urlopen(request)
        returned_json = response.read()
        oauth_object = json.loads(returned_json)
        return oauth_object
    
    except urllib2.HTTPError as e:
        if e.code == 401: # unauthorized (wrong username / pass)
            return None
        else:
            return e
    except ValueError as e:
        # JSON had an issue decoding the response.
        # Pass this exception down the chain.
        return e


# Step 2: Access the Ghost endpoints
#
# We specifically need to interface with the posts API
# https://github.com/TryGhost/Ghost/wiki/%5BWIP%5D-API-Documentation#posts

def make_new_post(md, title, access_token, url, tags=None, status='published'):
    """Creates a new post on the server from the API url supplied.
    Returns post object if successful, raises some error otherwise.
    """

    if not (md and title and access_token and url):
        raise ValueError('Expected 3 arguments: (markdown, token, url)')

    headers = {
        'Content-Type': 'application/json',
        'User-Agent': USER_AGENT,
        'Authorization': 'Bearer ' + access_token
        }
    data = json.dumps({
        'posts': [
            {
                'status': status, # should be either 'published' or 'draft'
                'author': '1', # the default user
                'title': title,
                'markdown': md,
                'tags': tags
            }]
        })
    request = urllib2.Request(url, data=data, headers=headers)
    
    response = urllib2.urlopen(request)
    return json.loads(response.read())