Merge lp:~terrycojones/txfluiddb/add-exists-tests-for-namespaces-and-tags into lp:txfluiddb

[Terry Jones]

Adds 'exists' methods to Namespace and Tag to check if they exist.

[lp:~terrycojones/txfluiddb/add-exists-tests-for-namespaces-and-tags]

16. By Terry Jones on 2011-07-31

Bumped version number.

[Tristan Seligmann (mithrandi)]

Yay! Sorry it took so long to get around to reviewing this, but at least it's a positive review :)

review: Approve

Unmerged revisions

16. By Terry Jones on 2011-07-31

Bumped version number.

15. By Terry Jones on 2011-07-31

Added exists methods to Namespace and Tag classes.

=== modified file 'setup.py'
--- setup.py	2010-09-15 12:14:01 +0000
+++ setup.py	2011-07-31 21:39:23 +0000
@@ -5,7 +5,7 @@
 
 setup(
     name = 'txfluiddb',
-    version = '0.1.0',
+    version = '0.1.1',
     packages = ['txfluiddb'],
     author = 'Tristan Seligmann',
 )

=== modified file 'txfluiddb/client.py'
--- txfluiddb/client.py	2010-06-13 21:53:12 +0000
+++ txfluiddb/client.py	2011-07-31 21:39:23 +0000
@@ -5,7 +5,7 @@
 import simplejson as json
 
 from txfluiddb.errors import InvalidName, InvalidTagValueType
-from txfluiddb.http import getPage
+from txfluiddb.http import getPage, HTTPError
 
 
 
@@ -315,6 +315,36 @@
                                method='DELETE')
 
 
+    def exists(self, endpoint):
+        """
+        Try a GET on the namespace to see if it exists.
+
+        @type  endpoint: L{Endpoint}
+        @param endpoint: The endpoint to operate through.
+
+        @rtype:  C{Deferred} -> C{bool}
+        @return: C{True} if the namespace exists, else C{False}.
+        """
+        def checkNonexistent(fail):
+            """
+            Return C{False} if the failure is due to a nonexistent namespace,
+            else return the original failure.
+
+            @type fail: C{twisted.python.fail.Failure}
+            @param fail: The failure.
+            """
+            fail.trap(HTTPError)
+            errorClass = fail.value.response_headers.get(
+                'x-fluiddb-error-class')
+            if errorClass and errorClass[0] == 'TNonexistentNamespace':
+                return False
+            return fail
+
+        url = self.getURL(endpoint)
+        d = endpoint.submit(url=url, method='GET')
+        return d.addCallbacks(lambda _: True, checkNonexistent)
+
+
 
 class Tag(_HasPath, _HasPerms):
     """
@@ -368,6 +398,36 @@
                                method='DELETE')
 
 
+    def exists(self, endpoint):
+        """
+        Try a GET on the tag to see if it exists.
+
+        @type  endpoint: L{Endpoint}
+        @param endpoint: The endpoint to operate through.
+
+        @rtype:  C{Deferred} -> C{bool}
+        @return: C{True} if the tag exists, else C{False}.
+        """
+        def checkNonexistent(fail):
+            """
+            Return C{False} if the failure is due to a nonexistent tag,
+            else return the original failure.
+
+            @type fail: C{twisted.python.fail.Failure}
+            @param fail: The failure.
+            """
+            fail.trap(HTTPError)
+            errorClass = fail.value.response_headers.get(
+                'x-fluiddb-error-class')
+            if errorClass and errorClass[0] == 'TNonexistentTag':
+                return False
+            return fail
+
+        url = self.getURL(endpoint)
+        d = endpoint.submit(url=url, method='GET')
+        return d.addCallbacks(lambda _: True, checkNonexistent)
+
+
 
 class TagValues(_HasPath, _HasPerms):
     """

=== modified file 'txfluiddb/test/test_client.py'
--- txfluiddb/test/test_client.py	2010-06-13 21:53:12 +0000
+++ txfluiddb/test/test_client.py	2011-07-31 21:39:23 +0000
@@ -1,11 +1,12 @@
 from twisted.trial.unittest import TestCase
-from twisted.internet.defer import succeed
+from twisted.internet.defer import succeed, fail
 
 import simplejson as json
 
 from txfluiddb.errors import InvalidName
 from txfluiddb.client import (
     Namespace, Tag, Endpoint, _HasPath, Object, Blob, BasicCreds, loads)
+from txfluiddb.http import HTTPError
 
 
 
@@ -365,6 +366,49 @@
         return d
 
 
+    def test_existent(self):
+        """
+        Test retrieving a namespace that exists.
+        """
+        self.endpoint = MockEndpoint('http://fluiddb.url/')
+        response = True
+        self.endpoint.response = json.dumps(response)
+
+        def _gotResult(result):
+            self.assertEqual(True, result)
+
+        d = self.namespace.exists(self.endpoint).addCallback(_gotResult)
+        self.assertEqual(self.endpoint.method, 'GET')
+        self.assertEqual(
+            self.endpoint.url,
+            'http://fluiddb.url/namespaces/test')
+        self.assertEqual(self.endpoint.data, None)
+        return d
+
+
+    def test_nonexistent(self):
+        """
+        Test retrieving a namespace that does not exist.
+        """
+        self.endpoint = MockFailingEndpoint('http://fluiddb.url/')
+        response = False
+        self.endpoint.response = json.dumps(response)
+        self.endpoint.responseHeaders = {
+            'x-fluiddb-error-class' : ['TNonexistentNamespace']
+            }
+
+        def _gotResult(result):
+            self.assertEqual(False, result)
+
+        d = self.namespace.exists(self.endpoint).addErrback(_gotResult)
+        self.assertEqual(self.endpoint.method, 'GET')
+        self.assertEqual(
+            self.endpoint.url,
+            'http://fluiddb.url/namespaces/test')
+        self.assertEqual(self.endpoint.data, None)
+        return d
+
+
 
 class TagTests(TestCase):
     """
@@ -474,6 +518,49 @@
         return d
 
 
+    def test_existent(self):
+        """
+        Test retrieving a tag that exists.
+        """
+        self.endpoint = MockEndpoint('http://fluiddb.url/')
+        response = True
+        self.endpoint.response = json.dumps(response)
+
+        def _gotResult(result):
+            self.assertEqual(True, result)
+
+        d = self.tag.exists(self.endpoint).addCallback(_gotResult)
+        self.assertEqual(self.endpoint.method, 'GET')
+        self.assertEqual(
+            self.endpoint.url,
+            'http://fluiddb.url/tags/test/atag')
+        self.assertEqual(self.endpoint.data, None)
+        return d
+
+
+    def test_nonexistent(self):
+        """
+        Test retrieving a tag that does not exist.
+        """
+        self.endpoint = MockFailingEndpoint('http://fluiddb.url/')
+        response = False
+        self.endpoint.response = json.dumps(response)
+        self.endpoint.responseHeaders = {
+            'x-fluiddb-error-class' : ['TNonexistentTag']
+            }
+
+        def _gotResult(result):
+            self.assertEqual(False, result)
+
+        d = self.tag.exists(self.endpoint).addErrback(_gotResult)
+        self.assertEqual(self.endpoint.method, 'GET')
+        self.assertEqual(
+            self.endpoint.url,
+            'http://fluiddb.url/tags/test/atag')
+        self.assertEqual(self.endpoint.data, None)
+        return d
+
+
 class TagValuesTests(TestCase):
     """
     Tests for L{TagValues}.  Note that these are tests on the permissions
@@ -557,6 +644,27 @@
 
 
 
+class MockFailingEndpoint(Endpoint):
+    """
+    Endpoint with (failing) submit mocked out.
+    """
+    def getPage(self, url, method, postdata=None, headers=None, *a, **kw):
+        """
+        Store our parameters instead of submitting a request.
+        """
+        if method == 'GET' and postdata is not None:
+            raise RuntimeError('GET requests should never include postdata.')
+        self.url = url
+        self.method = method
+        self.data = postdata
+        self.headers = headers
+        rc = self.responseCode if hasattr(self, 'responseCode') else 400
+        message = self.message if hasattr(self, 'message') else ''
+        rh = self.responseHeaders if hasattr(self, 'responseHeaders') else {}
+        return fail(HTTPError(rc, message, self.response, rh))
+
+
+
 class EndpointTests(TestCase):
     """
     Tests for L{Endpoint}.