OwlCyberSecurity - MANAGER

Edit File: test_template.py

# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.

"""
Tests for L{twisted.web.template}
"""

from __future__ import division, absolute_import

from zope.interface.verify import verifyObject

from twisted.internet.defer import succeed, gatherResults
from twisted.python.filepath import FilePath
from twisted.trial.unittest import TestCase
from twisted.trial.util import suppress as SUPPRESS
from twisted.web.template import (
    Element, TagLoader, renderer, tags, XMLFile, XMLString)
from twisted.web.iweb import ITemplateLoader

from twisted.web.error import (FlattenerError, MissingTemplateLoader,
    MissingRenderMethod)

from twisted.web.template import renderElement
from twisted.web._element import UnexposedMethodError
from twisted.web.test._util import FlattenTestCase
from twisted.web.test.test_web import DummyRequest
from twisted.web.server import NOT_DONE_YET

from twisted.python.compat import NativeStringIO as StringIO
from twisted.logger import globalLogPublisher
from twisted.test.proto_helpers import EventLoggingObserver

_xmlFileSuppress = SUPPRESS(category=DeprecationWarning,
        message="Passing filenames or file objects to XMLFile is "
                "deprecated since Twisted 12.1.  Pass a FilePath instead.")

class TagFactoryTests(TestCase):
    """
    Tests for L{_TagFactory} through the publicly-exposed L{tags} object.
    """
    def test_lookupTag(self):
        """
        HTML tags can be retrieved through C{tags}.
        """
        tag = tags.a
        self.assertEqual(tag.tagName, "a")

def test_lookupHTML5Tag(self):
        """
        Twisted supports the latest and greatest HTML tags from the HTML5
        specification.
        """
        tag = tags.video
        self.assertEqual(tag.tagName, "video")

def test_lookupTransparentTag(self):
        """
        To support transparent inclusion in templates, there is a special tag,
        the transparent tag, which has no name of its own but is accessed
        through the "transparent" attribute.
        """
        tag = tags.transparent
        self.assertEqual(tag.tagName, "")

def test_lookupInvalidTag(self):
        """
        Invalid tags which are not part of HTML cause AttributeErrors when
        accessed through C{tags}.
        """
        self.assertRaises(AttributeError, getattr, tags, "invalid")

def test_lookupXMP(self):
 """
 As a special case, the <xmp> tag is simply not available through
 C{tags} or any other part of the templating machinery.
 """
 self.assertRaises(AttributeError, getattr, tags, "xmp")

class ElementTests(TestCase):
    """
    Tests for the awesome new L{Element} class.
    """
    def test_missingTemplateLoader(self):
        """
        L{Element.render} raises L{MissingTemplateLoader} if the C{loader}
        attribute is L{None}.
        """
        element = Element()
        err = self.assertRaises(MissingTemplateLoader, element.render, None)
        self.assertIdentical(err.element, element)

def test_missingTemplateLoaderRepr(self):
        """
        A L{MissingTemplateLoader} instance can be repr()'d without error.
        """
        class PrettyReprElement(Element):
            def __repr__(self):
                return 'Pretty Repr Element'
        self.assertIn('Pretty Repr Element',
                      repr(MissingTemplateLoader(PrettyReprElement())))

def test_missingRendererMethod(self):
        """
        When called with the name which is not associated with a render method,
        L{Element.lookupRenderMethod} raises L{MissingRenderMethod}.
        """
        element = Element()
        err = self.assertRaises(
            MissingRenderMethod, element.lookupRenderMethod, "foo")
        self.assertIdentical(err.element, element)
        self.assertEqual(err.renderName, "foo")

def test_missingRenderMethodRepr(self):
        """
        A L{MissingRenderMethod} instance can be repr()'d without error.
        """
        class PrettyReprElement(Element):
            def __repr__(self):
                return 'Pretty Repr Element'
        s = repr(MissingRenderMethod(PrettyReprElement(),
                                     'expectedMethod'))
        self.assertIn('Pretty Repr Element', s)
        self.assertIn('expectedMethod', s)

def test_definedRenderer(self):
        """
        When called with the name of a defined render method,
        L{Element.lookupRenderMethod} returns that render method.
        """
        class ElementWithRenderMethod(Element):
            @renderer
            def foo(self, request, tag):
                return "bar"
        foo = ElementWithRenderMethod().lookupRenderMethod("foo")
        self.assertEqual(foo(None, None), "bar")

def test_render(self):
        """
        L{Element.render} loads a document from the C{loader} attribute and
        returns it.
        """
        class TemplateLoader(object):
            def load(self):
                return "result"

class StubElement(Element):
            loader = TemplateLoader()

element = StubElement()
        self.assertEqual(element.render(None), "result")

def test_misuseRenderer(self):
        """
        If the L{renderer} decorator  is called without any arguments, it will
        raise a comprehensible exception.
        """
        te = self.assertRaises(TypeError, renderer)
        self.assertEqual(str(te),
                         "expose() takes at least 1 argument (0 given)")

def test_renderGetDirectlyError(self):
        """
        Called directly, without a default, L{renderer.get} raises
        L{UnexposedMethodError} when it cannot find a renderer.
        """
        self.assertRaises(UnexposedMethodError, renderer.get, None,
                          "notARenderer")

class XMLFileReprTests(TestCase):
 """
 Tests for L{twisted.web.template.XMLFile}'s C{__repr__}.
 """
 def test_filePath(self):
 """
 An L{XMLFile} with a L{FilePath} returns a useful repr().
 """
 path = FilePath("/tmp/fake.xml")
 self.assertEqual('<XMLFile of %r>' % (path,), repr(XMLFile(path)))

def test_filename(self):
 """
 An L{XMLFile} with a filename returns a useful repr().
 """
 fname = "/tmp/fake.xml"
 self.assertEqual('<XMLFile of %r>' % (fname,), repr(XMLFile(fname)))
 test_filename.suppress = [_xmlFileSuppress]

def test_file(self):
 """
 An L{XMLFile} with a file object returns a useful repr().
 """
 fobj = StringIO("not xml")
 self.assertEqual('<XMLFile of %r>' % (fobj,), repr(XMLFile(fobj)))
 test_file.suppress = [_xmlFileSuppress]

class XMLLoaderTestsMixin(object):
    """
    @ivar templateString: Simple template to use to exercise the loaders.

@ivar deprecatedUse: C{True} if this use of L{XMLFile} is deprecated and
        should emit a C{DeprecationWarning}.
    """

loaderFactory = None
 templateString = 'Hello, world.'
 def test_load(self):
 """
 Verify that the loader returns a tag with the correct children.
 """
 loader = self.loaderFactory()
 tag, = loader.load()

warnings = self.flushWarnings(offendingFunctions=[self.loaderFactory])
        if self.deprecatedUse:
            self.assertEqual(len(warnings), 1)
            self.assertEqual(warnings[0]['category'], DeprecationWarning)
            self.assertEqual(
                warnings[0]['message'],
                "Passing filenames or file objects to XMLFile is "
                "deprecated since Twisted 12.1.  Pass a FilePath instead.")
        else:
            self.assertEqual(len(warnings), 0)

self.assertEqual(tag.tagName, 'p')
        self.assertEqual(tag.children, [u'Hello, world.'])

def test_loadTwice(self):
        """
        If {load()} can be called on a loader twice the result should be the
        same.
        """
        loader = self.loaderFactory()
        tags1 = loader.load()
        tags2 = loader.load()
        self.assertEqual(tags1, tags2)
    test_loadTwice.suppress = [_xmlFileSuppress]

class XMLStringLoaderTests(TestCase, XMLLoaderTestsMixin):
    """
    Tests for L{twisted.web.template.XMLString}
    """
    deprecatedUse = False
    def loaderFactory(self):
        """
        @return: an L{XMLString} constructed with C{self.templateString}.
        """
        return XMLString(self.templateString)

class XMLFileWithFilePathTests(TestCase, XMLLoaderTestsMixin):
    """
    Tests for L{twisted.web.template.XMLFile}'s L{FilePath} support.
    """
    deprecatedUse = False
    def loaderFactory(self):
        """
        @return: an L{XMLString} constructed with a L{FilePath} pointing to a
            file that contains C{self.templateString}.
        """
        fp = FilePath(self.mktemp())
        fp.setContent(self.templateString.encode("utf8"))
        return XMLFile(fp)

class XMLFileWithFileTests(TestCase, XMLLoaderTestsMixin):
    """
    Tests for L{twisted.web.template.XMLFile}'s deprecated file object support.
    """
    deprecatedUse = True
    def loaderFactory(self):
        """
        @return: an L{XMLString} constructed with a file object that contains
            C{self.templateString}.
        """
        return XMLFile(StringIO(self.templateString))

class XMLFileWithFilenameTests(TestCase, XMLLoaderTestsMixin):
    """
    Tests for L{twisted.web.template.XMLFile}'s deprecated filename support.
    """
    deprecatedUse = True
    def loaderFactory(self):
        """
        @return: an L{XMLString} constructed with a filename that points to a
            file containing C{self.templateString}.
        """
        fp = FilePath(self.mktemp())
        fp.setContent(self.templateString.encode('utf8'))
        return XMLFile(fp.path)

class FlattenIntegrationTests(FlattenTestCase):
    """
    Tests for integration between L{Element} and
    L{twisted.web._flatten.flatten}.
    """

def test_roundTrip(self):
 """
 Given a series of parsable XML strings, verify that
 L{twisted.web._flatten.flatten} will flatten the L{Element} back to the
 input when sent on a round trip.
 """
 fragments = [
 b"Hello, world.",
 b"",
 b"<![CDATA[Hello, world.]]>",
 b'<test1 xmlns:test2="urn:test2">'
 b'<test2:test3></test2:test3></test1>',
 b'<test1 xmlns="urn:test2"><test3></test3></test1>',
 b'\xe2\x98\x83',
 ]
 deferreds = [
 self.assertFlattensTo(Element(loader=XMLString(xml)), xml)
 for xml in fragments]
 return gatherResults(deferreds)

def test_entityConversion(self):
 """
 When flattening an HTML entity, it should flatten out to the utf-8
 representation if possible.
 """
 element = Element(loader=XMLString('&#9731;'))
 return self.assertFlattensTo(element, b'\xe2\x98\x83')

def test_missingTemplateLoader(self):
        """
        Rendering an Element without a loader attribute raises the appropriate
        exception.
        """
        return self.assertFlatteningRaises(Element(), MissingTemplateLoader)

def test_missingRenderMethod(self):
 """
 Flattening an L{Element} with a C{loader} which has a tag with a render
 directive fails with L{FlattenerError} if there is no available render
 method to satisfy that directive.
 """
 element = Element(loader=XMLString("""
 
 """))
 return self.assertFlatteningRaises(element, MissingRenderMethod)

def test_transparentRendering(self):
 """
 A C{transparent} element should be eliminated from the DOM and rendered as
 only its children.
 """
 element = Element(loader=XMLString(
 '<t:transparent '
 'xmlns:t="http://twistedmatrix.com/ns/twisted.web.template/0.1">'
 'Hello, world.'
 '</t:transparent>'
 ))
 return self.assertFlattensTo(element, b"Hello, world.")

def test_attrRendering(self):
 """
 An Element with an attr tag renders the vaule of its attr tag as an
 attribute of its containing tag.
 """
 element = Element(loader=XMLString(
 '<a xmlns:t="http://twistedmatrix.com/ns/twisted.web.template/0.1">'
 '<t:attr name="href">http://example.com</t:attr>'
 'Hello, world.'
 '</a>'
 ))
 return self.assertFlattensTo(element,
 b'<a href="http://example.com">Hello, world.</a>')

def test_errorToplevelAttr(self):
 """
 A template with a toplevel C{attr} tag will not load; it will raise
 L{AssertionError} if you try.
 """
 self.assertRaises(
 AssertionError,
 XMLString,
 """<t:attr
 xmlns:t='http://twistedmatrix.com/ns/twisted.web.template/0.1'
 name='something'
 >hello</t:attr>
 """)

def test_errorUnnamedAttr(self):
 """
 A template with an C{attr} tag with no C{name} attribute will not load;
 it will raise L{AssertionError} if you try.
 """
 self.assertRaises(
 AssertionError,
 XMLString,
 """<html><t:attr
 xmlns:t='http://twistedmatrix.com/ns/twisted.web.template/0.1'
 >hello</t:attr></html>""")

def test_lenientPrefixBehavior(self):
 """
 If the parser sees a prefix it doesn't recognize on an attribute, it
 will pass it on through to serialization.
 """
 theInput = (
 '<hello:world hello:sample="testing" '
 'xmlns:hello="http://made-up.example.com/ns/not-real">'
 'This is a made-up tag.</hello:world>')
 element = Element(loader=XMLString(theInput))
 self.assertFlattensTo(element, theInput.encode('utf8'))

def test_deferredRendering(self):
 """
 An Element with a render method which returns a Deferred will render
 correctly.
 """
 class RenderfulElement(Element):
 @renderer
 def renderMethod(self, request, tag):
 return succeed("Hello, world.")
 element = RenderfulElement(loader=XMLString("""
 
 Goodbye, world.
 
 """))
 return self.assertFlattensTo(element, b"Hello, world.")

def test_loaderClassAttribute(self):
 """
 If there is a non-None loader attribute on the class of an Element
 instance but none on the instance itself, the class attribute is used.
 """
 class SubElement(Element):
 loader = XMLString("Hello, world.")
 return self.assertFlattensTo(SubElement(), b"Hello, world.")

def test_directiveRendering(self):
 """
 An Element with a valid render directive has that directive invoked and
 the result added to the output.
 """
 renders = []
 class RenderfulElement(Element):
 @renderer
 def renderMethod(self, request, tag):
 renders.append((self, request))
 return tag("Hello, world.")
 element = RenderfulElement(loader=XMLString("""
 
 """))
 return self.assertFlattensTo(element, b"Hello, world.")

def test_directiveRenderingOmittingTag(self):
 """
 An Element with a render method which omits the containing tag
 successfully removes that tag from the output.
 """
 class RenderfulElement(Element):
 @renderer
 def renderMethod(self, request, tag):
 return "Hello, world."
 element = RenderfulElement(loader=XMLString("""
 
 Goodbye, world.
 
 """))
 return self.assertFlattensTo(element, b"Hello, world.")

def test_elementContainingStaticElement(self):
 """
 An Element which is returned by the render method of another Element is
 rendered properly.
 """
 class RenderfulElement(Element):
 @renderer
 def renderMethod(self, request, tag):
 return tag(Element(
 loader=XMLString("Hello, world.")))
 element = RenderfulElement(loader=XMLString("""
 
 """))
 return self.assertFlattensTo(element, b"Hello, world.")

def test_elementUsingSlots(self):
 """
 An Element which is returned by the render method of another Element is
 rendered properly.
 """
 class RenderfulElement(Element):
 @renderer
 def renderMethod(self, request, tag):
 return tag.fillSlots(test2='world.')
 element = RenderfulElement(loader=XMLString(
 ''
 '<t:slot name="test1" default="Hello, " />'
 '<t:slot name="test2" />'
 ''
 ))
 return self.assertFlattensTo(element, b"Hello, world.")

def test_elementContainingDynamicElement(self):
 """
 Directives in the document factory of an Element returned from a render
 method of another Element are satisfied from the correct object: the
 "inner" Element.
 """
 class OuterElement(Element):
 @renderer
 def outerMethod(self, request, tag):
 return tag(InnerElement(loader=XMLString("""
 <t:ignored
 xmlns:t="http://twistedmatrix.com/ns/twisted.web.template/0.1"
 t:render="innerMethod" />
 """)))
 class InnerElement(Element):
 @renderer
 def innerMethod(self, request, tag):
 return "Hello, world."
 element = OuterElement(loader=XMLString("""
 
 """))
 return self.assertFlattensTo(element, b"Hello, world.")

def test_sameLoaderTwice(self):
 """
 Rendering the output of a loader, or even the same element, should
 return different output each time.
 """
 sharedLoader = XMLString(
 ''
 '<t:transparent t:render="classCounter" /> '
 '<t:transparent t:render="instanceCounter" />'
 '')

class DestructiveElement(Element):
            count = 0
            instanceCount = 0
            loader = sharedLoader

@renderer
            def classCounter(self, request, tag):
                DestructiveElement.count += 1
                return tag(str(DestructiveElement.count))
            @renderer
            def instanceCounter(self, request, tag):
                self.instanceCount += 1
                return tag(str(self.instanceCount))

e1 = DestructiveElement()
 e2 = DestructiveElement()
 self.assertFlattensImmediately(e1, b"1 1")
 self.assertFlattensImmediately(e1, b"2 2")
 self.assertFlattensImmediately(e2, b"3 1")

class TagLoaderTests(FlattenTestCase):
    """
    Tests for L{TagLoader}.
    """
    def setUp(self):
        self.loader = TagLoader(tags.i('test'))

def test_interface(self):
        """
        An instance of L{TagLoader} provides L{ITemplateLoader}.
        """
        self.assertTrue(verifyObject(ITemplateLoader, self.loader))

def test_loadsList(self):
        """
        L{TagLoader.load} returns a list, per L{ITemplateLoader}.
        """
        self.assertIsInstance(self.loader.load(), list)

def test_flatten(self):
 """
 L{TagLoader} can be used in an L{Element}, and flattens as the tag used
 to construct the L{TagLoader} would flatten.
 """
 e = Element(self.loader)
 self.assertFlattensImmediately(e, b'test')

class TestElement(Element):
 """
 An L{Element} that can be rendered successfully.
 """
 loader = XMLString(
 ''
 'Hello, world.'
 '')

class TestFailureElement(Element):
 """
 An L{Element} that can be used in place of L{FailureElement} to verify
 that L{renderElement} can render failures properly.
 """
 loader = XMLString(
 ''
 'I failed.'
 '')

def __init__(self, failure, loader=None):
        self.failure = failure

class FailingElement(Element):
    """
    An element that raises an exception when rendered.
    """
    def render(self, request):
        a = 42
        b = 0
        return a // b

class FakeSite(object):
    """
    A minimal L{Site} object that we can use to test displayTracebacks
    """
    displayTracebacks = False

class RenderElementTests(TestCase):
    """
    Test L{renderElement}
    """

def setUp(self):
        """
        Set up a common L{DummyRequest} and L{FakeSite}.
        """
        self.request = DummyRequest([""])
        self.request.site = FakeSite()

def test_simpleRender(self):
        """
        L{renderElement} returns NOT_DONE_YET and eventually
        writes the rendered L{Element} to the request before finishing the
        request.
        """
        element = TestElement()

d = self.request.notifyFinish()

def check(_):
 self.assertEqual(
 b"".join(self.request.written),
 b"<!DOCTYPE html>\n"
 b"Hello, world.")
 self.assertTrue(self.request.finished)

d.addCallback(check)

self.assertIdentical(NOT_DONE_YET, renderElement(self.request, element))

return d

def test_simpleFailure(self):
        """
        L{renderElement} handles failures by writing a minimal
        error message to the request and finishing it.
        """
        element = FailingElement()

d = self.request.notifyFinish()

def check(_):
 flushed = self.flushLoggedErrors(FlattenerError)
 self.assertEqual(len(flushed), 1)
 self.assertEqual(
 b"".join(self.request.written),
 (b'<!DOCTYPE html>\n'
 b'<div style="font-size:800%;'
 b'background-color:#FFF;'
 b'color:#F00'
 b'">An error occurred while rendering the response.</div>'))
 self.assertTrue(self.request.finished)

d.addCallback(check)

self.assertIdentical(NOT_DONE_YET, renderElement(self.request, element))

return d

def test_simpleFailureWithTraceback(self):
        """
        L{renderElement} will render a traceback when rendering of
        the element fails and our site is configured to display tracebacks.
        """
        logObserver = EventLoggingObserver.createWithCleanup(
            self,
            globalLogPublisher
        )
        self.request.site.displayTracebacks = True

element = FailingElement()

d = self.request.notifyFinish()

def check(_):
 self.assertEquals(1, len(logObserver))
 f = logObserver[0]["log_failure"]
 self.assertIsInstance(f.value, FlattenerError)
 flushed = self.flushLoggedErrors(FlattenerError)
 self.assertEqual(len(flushed), 1)
 self.assertEqual(
 b"".join(self.request.written),
 b"<!DOCTYPE html>\nI failed.")
 self.assertTrue(self.request.finished)

d.addCallback(check)

renderElement(self.request, element, _failElement=TestFailureElement)

return d

def test_nonDefaultDoctype(self):
        """
        L{renderElement} will write the doctype string specified by the
        doctype keyword argument.
        """
        element = TestElement()

d = self.request.notifyFinish()

def check(_):
 self.assertEqual(
 b"".join(self.request.written),
 (b'<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"'
 b' "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">\n'
 b'Hello, world.'))

d.addCallback(check)

renderElement(
 self.request,
 element,
 doctype=(
 b'<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"'
 b' "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">'))

return d

def test_noneDoctype(self):
        """
        L{renderElement} will not write out a doctype if the doctype keyword
        argument is L{None}.
        """
        element = TestElement()

d = self.request.notifyFinish()

def check(_):
 self.assertEqual(
 b"".join(self.request.written),
 b'Hello, world.')

d.addCallback(check)

renderElement(self.request, element, doctype=None)

return d