Fork Canonical's thin-client-config-agent script and maintain it in the Arctica Project's namespace.

2 files changed, 463 insertions, 0 deletions

diff --git a/tccalib/__init__.py b/tccalib/__init__.py
new file mode 100644
index 0000000..9c61844
--- /dev/null
+++ b/tccalib/__init__.py
@@ -0,0 +1,224 @@
+# Copyright 2012 Canonical Ltd.  This software is licensed under the GNU
+# General Public License version 3 (see the file LICENSE).
+
+__metaclass__ = type
+
+
+import errno
+from http.client import parse_headers
+import socket
+from io import BytesIO, StringIO
+from urllib.parse import quote
+import urllib.request, urllib.error
+import base64
+
+import pycurl
+
+
+class UserError(Exception):
+    """An error message that should be presented to the user."""
+
+    def __init__(self, msg=None):
+        if msg is None:
+            msg = self.__doc__
+        super(UserError, self).__init__(msg)
+
+
+class Unauthorized(UserError):
+    """Invalid username or password"""
+
+    status = 2
+
+
+class CouldNotConnect(UserError):
+    """Could not connect"""
+
+    status = 3
+
+
+class CertificateVerificationFailed(UserError):
+    """Certificate verification failed"""
+
+    status = 4
+
+
+class URLLibGetter:
+    """Get data from URLs using URLib."""
+
+    @staticmethod
+    def get_response_body(request, verify_ssl):
+        """Return the body of the response to the supplied request.
+
+        :param request: A urllib2.Request
+        :param verify_ssl: Unused
+        :raises CouldNotConnect: if there is a connection error.
+        """
+        try:
+            return urllib.request.urlopen(request).read()
+        except urllib.error.URLError as e:
+            if not isinstance(e.args[0], socket.error):
+                raise
+            if e.args[0].errno == errno.ECONNREFUSED:
+                raise CouldNotConnect
+            raise
+
+
+class PycURLGetter:
+    """Get data from URLs using PycURL."""
+
+    def __init__(self, _curl=None):
+        if _curl is None:
+            _curl = pycurl.Curl()
+        self.curl = _curl
+        self.result = BytesIO()
+        self.response_header = BytesIO()
+        self.curl.setopt(pycurl.HEADERFUNCTION, self.response_header.write)
+        self.curl.setopt(pycurl.WRITEFUNCTION, self.result.write)
+        self.verify_ssl = True
+
+    def prepare_curl(self, request):
+        """Prepare the curl object for the supplied request.
+
+        :param request: a urllib2.Request instance.
+        """
+        self.curl.setopt(pycurl.URL, request.get_full_url())
+        request_headers = ['%s: %s' % item for
+                           item in list(request.headers.items())]
+        self.curl.setopt(pycurl.HTTPHEADER, request_headers)
+        self.curl.setopt(pycurl.SSL_VERIFYPEER, self.verify_ssl)
+
+    @classmethod
+    def get_response_body(cls, request, verify_ssl=True, _curl=None):
+        """Return the body of the response to the supplied request.
+
+        :param request: A urllib2.Request instance.
+        :param verify_ssl: If true, verify SSL certificates.
+        :param _curl: The pycurl.Curl object to use (for testing).
+        :raises CouldNotConnect: if there is a connection error.
+        :raises CertificateVerificationFailed: if the SSL certificate could
+            not be verified.
+        :raises HTTPError: if the response status is not 200.
+        """
+        instance = cls(_curl)
+        instance.verify_ssl = verify_ssl
+        instance.prepare_curl(request)
+        return instance.handle_response()
+
+    def handle_response(self):
+        """Perform the curl operation and handle the response.
+
+        :return: The body of the response on success.
+        :raises CouldNotConnect: if there is a connection error.
+        :raises CertificateVerificationFailed: if the SSL certificate could
+            not be verified.
+        :raises HTTPError: if the response status is not 200.
+        """
+        try:
+            self.curl.perform()
+        except pycurl.error as e:
+            if e.args[0] in (pycurl.E_COULDNT_CONNECT,
+                pycurl.E_COULDNT_RESOLVE_HOST):
+                    raise CouldNotConnect
+            elif e.args[0] == pycurl.E_SSL_CACERT:
+                raise CertificateVerificationFailed
+            else:
+                raise
+        status = self.curl.getinfo(pycurl.HTTP_CODE)
+        if status == 200:
+            return self.result.getvalue().decode('utf-8')
+        else:
+            lines = self.response_header.getvalue().decode('utf-8').splitlines(True)
+            header_ = ''.join(lines[1:])
+            headers = parse_headers(BytesIO(header_.encode('ascii')))
+            raise urllib.error.HTTPError(
+                self.curl.getinfo(pycurl.EFFECTIVE_URL), status,
+                self.result.getvalue(), headers, None)
+
+
+class GetMazaData:
+    """Base class for retrieving data from MAZA server."""
+
+    @classmethod
+    def run(cls, username, password, server_root=None, verify_ssl=True):
+        """Return the requested data.
+
+        :param username: The username of the user.
+        :param password: The user's password.
+        :param server_root: The root URL to make queries to.
+        :param verify_ssl: If true, verify SSL certificates.
+        """
+        return cls(username, password, server_root).get_data(verify_ssl)
+
+    def __init__(self, username, password, server_root=None):
+        self.username = username
+        self.password = password
+        if server_root is not None:
+            self.server_root = server_root
+        else:
+            self.server_root = 'https://uccs.landscape.canonical.com'
+        self.getter = PycURLGetter
+
+    def get_api_url(self):
+        """Return the URL for an API version."""
+        return '%s/api/%s/' % (self.server_root, self.api_version)
+
+    def get_data(self, verify_ssl=True):
+        """Return the data for this version of the API."""
+        try:
+            return self.getter.get_response_body(self.make_request(),
+                                                 verify_ssl)
+        except urllib.error.HTTPError as e:
+            if e.getcode() == 401:
+                raise Unauthorized
+            else:
+                raise
+
+
+class GetMazaDataAPI1(GetMazaData):
+    """Get the maza data for a given email and password via API v1."""
+
+    api_version = 1
+
+    def make_request(self):
+        path = '%s/%s' % (quote(self.username), quote(self.password))
+        return urllib.request.Request(self.get_api_url() + path)
+
+
+class GetMazaDataAPI4(GetMazaData):
+    """Get the maza data for a given email and password via API v4."""
+    api_version = 4
+
+    def get_url(self):
+        return self.get_api_url()
+
+    def make_request(self):
+        request = urllib.request.Request(self.get_url())
+        credentials = '%s:%s' % (self.username, self.password)
+        credentials64 = base64.encodebytes(credentials.encode('ascii'))
+        authorization = 'Basic %s' % credentials64.decode('ascii')
+        request.add_header('Authorization', authorization)
+        return request
+
+
+class GetMazaDataAPI3(GetMazaDataAPI4):
+    """Get the maza data for a given email and password via API v3."""
+
+    api_version = 3
+
+    def get_url(self):
+        return self.get_api_url() + quote(self.username)
+
+
+class GetMazaDataAPI2(GetMazaDataAPI3):
+    """Get the maza data for a given email and password via API v2."""
+
+    api_version = 2
+
+
+api_versions = {
+    '1': GetMazaDataAPI1,
+    '2': GetMazaDataAPI2,
+    '3': GetMazaDataAPI3,
+    '4': GetMazaDataAPI4,
+    'default': GetMazaDataAPI4,
+}
diff --git a/tccalib/tests/__init__.py b/tccalib/tests/__init__.py
new file mode 100644
index 0000000..6323600
--- /dev/null
+++ b/tccalib/tests/__init__.py
@@ -0,0 +1,239 @@
+# Copyright 2012 Canonical Ltd.  This software is licensed under the GNU
+# General Public License version 3 (see the file LICENSE).
+
+
+__metaclass__ = type
+
+
+import urllib.request, urllib.error, urllib.parse
+from unittest import TestCase
+import base64
+
+import pycurl
+from io import BytesIO
+
+from tccalib import (
+    CertificateVerificationFailed,
+    CouldNotConnect,
+    GetMazaData,
+    GetMazaDataAPI1,
+    GetMazaDataAPI2,
+    GetMazaDataAPI3,
+    GetMazaDataAPI4,
+    PycURLGetter,
+    Unauthorized,
+    )
+
+
+class FakeGetResponseBody:
+    """Fake to raise a 401 when get_response_body is called."""
+
+    def get_response_body(self, request, verify_ssl):
+        raise urllib.error.HTTPError(None, 401, None, None, None)
+
+
+class GetMazaDataFaked(GetMazaData):
+    """Subclass of GetMazaData for testing."""
+
+    api_version = 34
+
+    def __init__(self, username=None, server_root=None):
+        super(GetMazaDataFaked, self).__init__(username, username, server_root)
+
+    def make_request(self):
+        pass
+
+
+class TestGetMazaData(TestCase):
+
+    def test_get_data_unauthorized(self):
+        """If a 401 is encountered, Unauthorized is raised."""
+        api_client = GetMazaDataFaked()
+        api_client.getter = FakeGetResponseBody()
+        with self.assertRaises(Unauthorized):
+            api_client.get_data()
+
+    def test_get_api_url_default(self):
+        """Default URL is as expected."""
+        url = GetMazaDataFaked().get_api_url()
+        self.assertEqual('https://uccs.landscape.canonical.com/api/34/',
+                         url)
+
+    def test_get_api_url_explicit(self):
+        """URL is as expected with specified server_root."""
+        url = GetMazaDataFaked(server_root='http://foo').get_api_url()
+        self.assertEqual('http://foo/api/34/', url)
+
+
+class TestGetMazaDataAPI1(TestCase):
+
+    def test_make_request(self):
+        """v1 requests have correct URL and no Auth header."""
+        getter = GetMazaDataAPI1('foo', 'bar')
+        request = getter.make_request()
+        self.assertEqual('https://uccs.landscape.canonical.com/api/1/foo/bar',
+                         request.get_full_url())
+        self.assertIs(None, request.headers.get('Authorization'))
+
+
+class TestGetMazaDataAPI2(TestCase):
+
+    def test_make_request(self):
+        """v2 requests have correct URL and Auth header."""
+        getter = GetMazaDataAPI2('foo', 'bar')
+        request =  getter.make_request()
+        credentials = base64.encodebytes(b'foo:bar').decode('ascii')
+        expected = 'Basic %s' % credentials
+        self.assertEqual('GET', request.get_method())
+        self.assertEqual('https://uccs.landscape.canonical.com/api/2/foo',
+                         request.get_full_url())
+        self.assertEqual(expected, request.headers['Authorization'])
+
+
+class TestGetMazaDataAPI3(TestCase):
+
+    def test_make_request(self):
+        """v3 requests have correct URL and Auth header."""
+        getter = GetMazaDataAPI3('foo', 'bar')
+        request =  getter.make_request()
+        credentials = base64.encodebytes(b'foo:bar').decode('ascii')
+        expected = 'Basic %s' % credentials
+        self.assertEqual('GET', request.get_method())
+        self.assertEqual('https://uccs.landscape.canonical.com/api/3/foo',
+                         request.get_full_url())
+        self.assertEqual(expected, request.headers['Authorization'])
+
+
+class TestGetMazaDataAPI4(TestCase):
+
+    def test_make_request(self):
+        """v4 requests have correct URL and Auth header."""
+        getter = GetMazaDataAPI4('foo', 'bar')
+        request =  getter.make_request()
+        credentials = base64.encodebytes(b'foo:bar').decode('ascii')
+        expected = 'Basic %s' % credentials
+        self.assertEqual('GET', request.get_method())
+        self.assertEqual('https://uccs.landscape.canonical.com/api/4/',
+                         request.get_full_url())
+        self.assertEqual(expected, request.headers['Authorization'])
+
+
+class FakeCurl:
+    """Fake pycurl.Curl for testing PycURLGetter."""
+
+    def __init__(self, response_status=200, body='', header='',
+                 effective_url='http://example.org/', perform_error=None):
+        self.options = {}
+        self.info = {}
+        self.response_status = response_status
+        self.response_header = bytes(header, 'UTF-8')
+        self.response_body = bytes(body, 'UTF-8')
+        self.effective_url=effective_url
+        self.perform_error = perform_error
+
+    def setopt(self, key, value):
+        self.options[key] = value
+
+    def perform(self):
+        if self.perform_error is not None:
+            raise self.perform_error
+        self.info[pycurl.EFFECTIVE_URL] = self.effective_url
+        self.info[pycurl.HTTP_CODE] = self.response_status
+        self.options[pycurl.HEADERFUNCTION](self.response_header)
+        self.options[pycurl.WRITEFUNCTION](self.response_body)
+
+    def getinfo(self, key):
+        return self.info[key]
+
+
+class TestPycURLGetter(TestCase):
+
+    def test_init(self):
+        """Init should set the WRITEFUNCTION and HEADERFUNCTION."""
+        getter = PycURLGetter(FakeCurl())
+        options = getter.curl.options
+        self.assertIsNot(None, options[pycurl.WRITEFUNCTION])
+        self.assertIsNot(None, options[pycurl.HEADERFUNCTION])
+
+    @staticmethod
+    def make_request():
+        return GetMazaDataAPI3('pete', 'pass').make_request()
+
+    def test_prepare_curl(self):
+        """prepare_curl sets URL and auth header."""
+        curl = FakeCurl()
+        getter = PycURLGetter(curl)
+        request = self.make_request()
+        getter.prepare_curl(request)
+        self.assertEqual(request.get_full_url(), curl.options[pycurl.URL])
+        self.assertEqual(['Authorization: Basic cGV0ZTpwYXNz\n'],
+                         curl.options[pycurl.HTTPHEADER])
+
+    def test_prepare_curl_ssl_verify(self):
+        """SSL cert verification can be disabled for testing purposes."""
+        curl = FakeCurl()
+        getter = PycURLGetter(curl)
+        getter.prepare_curl(self.make_request())
+        self.assertTrue(curl.options[pycurl.SSL_VERIFYPEER])
+        getter.verify_ssl = False
+        getter.prepare_curl(self.make_request())
+        self.assertFalse(curl.options[pycurl.SSL_VERIFYPEER])
+
+    def test_handle_reponse(self):
+        """On success, handle_response returns response body."""
+        curl = FakeCurl(body='My body!', header='My header!',
+                        effective_url='http://example.com/')
+        getter = PycURLGetter(curl)
+        output = getter.handle_response()
+        self.assertEqual('My body!', output)
+        self.assertEqual('My header!', getter.response_header.getvalue().decode('UTF-8'))
+        self.assertEqual('http://example.com/',
+                         getter.curl.getinfo(pycurl.EFFECTIVE_URL))
+
+    def test_handle_response_http_error(self):
+        """On http error, handle_response raises urllib.error.HTTPError."""
+        curl = FakeCurl(500, 'My body!', '\nContent-type: fake\n\n')
+        getter = PycURLGetter(curl)
+        try:
+            getter.handle_response()
+        except urllib.error.HTTPError as e:
+            httpe = e
+        else:
+            self.fail('No error was raised.')
+        try:
+            httpe.geturl()
+        except AttributeError as attre:
+            self.assertEqual("'HTTPError' object has no attribute 'url'",
+                             str(attre))
+        self.assertEqual(500, httpe.getcode())
+        self.assertEqual('My body!', httpe.msg.decode('UTF-8'))
+        self.assertEqual([('Content-type', 'fake')], httpe.hdrs.items())
+
+    def test_handle_response_connection_error(self):
+        """On connection error, handle_response raises CouldNotConnect."""
+        error = pycurl.error(pycurl.E_COULDNT_CONNECT)
+        getter = PycURLGetter(FakeCurl(perform_error=error))
+        with self.assertRaises(CouldNotConnect):
+            getter.handle_response()
+
+    def test_cert_verification_failed(self):
+        """Cert verification error raises CertificateVerificationFailed."""
+        error = pycurl.error(pycurl.E_SSL_CACERT)
+        getter = PycURLGetter(FakeCurl(perform_error=error))
+        with self.assertRaises(CertificateVerificationFailed):
+            getter.handle_response()
+
+    def test_handle_response_pycurl_error(self):
+        """PycURLGetter allows other errors to propagate."""
+        error = pycurl.error(pycurl.E_MULTI_OUT_OF_MEMORY)
+        getter = PycURLGetter(FakeCurl(perform_error=error))
+        with self.assertRaises(pycurl.error):
+            getter.handle_response()
+
+    def test_get_response_body(self):
+        """On success, get_response_body returns response body."""
+        curl = FakeCurl(body='My body!', header='My header!',
+                        effective_url='http://example.com/')
+        request = GetMazaDataAPI3('pete', 'pass').make_request()
+        output = PycURLGetter.get_response_body(request, _curl=curl)
+        self.assertEqual('My body!', output)