Source code for pyvo.auth.authurls

import collections
import logging

from . import securitymethods

__all__ = ["AuthURLs"]

[docs]class AuthURLs(): """ AuthURLs helps determine which security method should be used with a given URL. It learns the security methods through the VOSI capabilities, which are passed in via update_from_capabilities. """ def __init__(self): self.full_urls = collections.defaultdict(set) self.base_urls = collections.defaultdict(set)
[docs] def update_from_capabilities(self, capabilities): """ Update the URL to security method mapping using the capabilities provided. Parameters ---------- capabilities : object List of `` """ for c in capabilities: for i in c.interfaces: for u in i.accessurls: url = u.content exact = u.use == 'full' if not i.securitymethods: self.add_security_method_for_url(url, securitymethods.ANONYMOUS, exact) for sm in i.securitymethods: method = sm.standardid or securitymethods.ANONYMOUS self.add_security_method_for_url(url, method, exact)
[docs] def add_security_method_for_url(self, url, security_method, exact=False): """ Add a security method for a url. This is additive with update_from_capabilities. This can be useful to set additional security methods that aren't set in the capabilities for whatever reason. Parameters ---------- url : str URL to set a security method for security_method : str URI of the security method to set exact : bool If True, match only this URL. If false, match all URLs that match this as a base URL. """ if exact: self.full_urls[url].add(security_method) else: self.base_urls[url].add(security_method)
[docs] def allowed_auth_methods(self, url): """ Return the authentication methods allowed for a particular URL. The methods are returned as URIs that represent security methods. Parameters ---------- url : str the URL to determine authentication methods """ logging.debug('Determining auth method for %s', url) if url in self.full_urls: methods = self.full_urls[url] logging.debug('Matching full url %s, methods %s', url, methods) return methods for base_url, methods in self._iterate_base_urls(): if url.startswith(base_url): logging.debug('Matching base url %s, methods %s', base_url, methods) return methods logging.debug('No match, using anonymous auth') return {securitymethods.ANONYMOUS}
def _iterate_base_urls(self): """ A generator to sort the base URLs in the correct way to determine the most specific base_url. This is done by returning them longest to shortest. """ def sort_by_len(x): return len(x[0]) # Sort the base path matching URLs, so that # the longest URLs (the most specific ones, if # there is a tie) are used to determine the # auth method. for url, method in sorted(self.base_urls.items(), key=sort_by_len, reverse=True): yield url, method def __repr__(self): urls = [] for url, methods in self.full_urls.items(): urls.append('Full match:' + url + ':' + str(methods)) for url, methods in self._iterate_base_urls(): urls.append('Base match:' + url + ':' + str(methods)) return '\n'.join(urls)