CasperSecurity
# -*- test-case-name: twisted.web.test.test_script -*-
# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.
"""
I contain PythonScript, which is a very simple python script resource.
"""
import os
import traceback
from io import StringIO
from twisted import copyright
from twisted.python.compat import execfile, networkString
from twisted.python.filepath import _coerceToFilesystemEncoding
from twisted.web import http, resource, server, static, util
rpyNoResource = """<p>You forgot to assign to the variable "resource" in your script. For example:</p>
<pre>
# MyCoolWebApp.rpy
import mygreatresource
resource = mygreatresource.MyGreatResource()
</pre>
"""
class AlreadyCached(Exception):
"""
This exception is raised when a path has already been cached.
"""
class CacheScanner:
def __init__(self, path, registry):
self.path = path
self.registry = registry
self.doCache = 0
def cache(self):
c = self.registry.getCachedPath(self.path)
if c is not None:
raise AlreadyCached(c)
self.recache()
def recache(self):
self.doCache = 1
noRsrc = resource.ErrorPage(500, "Whoops! Internal Error", rpyNoResource)
def ResourceScript(path, registry):
"""
I am a normal py file which must define a 'resource' global, which should
be an instance of (a subclass of) web.resource.Resource; it will be
renderred.
"""
cs = CacheScanner(path, registry)
glob = {
"__file__": _coerceToFilesystemEncoding("", path),
"resource": noRsrc,
"registry": registry,
"cache": cs.cache,
"recache": cs.recache,
}
try:
execfile(path, glob, glob)
except AlreadyCached as ac:
return ac.args[0]
rsrc = glob["resource"]
if cs.doCache and rsrc is not noRsrc:
registry.cachePath(path, rsrc)
return rsrc
def ResourceTemplate(path, registry):
from quixote import ptl_compile # type: ignore[import]
glob = {
"__file__": _coerceToFilesystemEncoding("", path),
"resource": resource.ErrorPage(500, "Whoops! Internal Error", rpyNoResource),
"registry": registry,
}
with open(path) as f: # Not closed by quixote as of 2.9.1
e = ptl_compile.compile_template(f, path)
code = compile(e, "<source>", "exec")
eval(code, glob, glob)
return glob["resource"]
class ResourceScriptWrapper(resource.Resource):
def __init__(self, path, registry=None):
resource.Resource.__init__(self)
self.path = path
self.registry = registry or static.Registry()
def render(self, request):
res = ResourceScript(self.path, self.registry)
return res.render(request)
def getChildWithDefault(self, path, request):
res = ResourceScript(self.path, self.registry)
return res.getChildWithDefault(path, request)
class ResourceScriptDirectory(resource.Resource):
"""
L{ResourceScriptDirectory} is a resource which serves scripts from a
filesystem directory. File children of a L{ResourceScriptDirectory} will
be served using L{ResourceScript}. Directory children will be served using
another L{ResourceScriptDirectory}.
@ivar path: A C{str} giving the filesystem path in which children will be
looked up.
@ivar registry: A L{static.Registry} instance which will be used to decide
how to interpret scripts found as children of this resource.
"""
def __init__(self, pathname, registry=None):
resource.Resource.__init__(self)
self.path = pathname
self.registry = registry or static.Registry()
def getChild(self, path, request):
fn = os.path.join(self.path, path)
if os.path.isdir(fn):
return ResourceScriptDirectory(fn, self.registry)
if os.path.exists(fn):
return ResourceScript(fn, self.registry)
return resource.NoResource()
def render(self, request):
return resource.NoResource().render(request)
class PythonScript(resource.Resource):
"""
I am an extremely simple dynamic resource; an embedded python script.
This will execute a file (usually of the extension '.epy') as Python code,
internal to the webserver.
"""
isLeaf = True
def __init__(self, filename, registry):
"""
Initialize me with a script name.
"""
self.filename = filename
self.registry = registry
def render(self, request):
"""
Render me to a web client.
Load my file, execute it in a special namespace (with 'request' and
'__file__' global vars) and finish the request. Output to the web-page
will NOT be handled with print - standard output goes to the log - but
with request.write.
"""
request.setHeader(
b"x-powered-by", networkString("Twisted/%s" % copyright.version)
)
namespace = {
"request": request,
"__file__": _coerceToFilesystemEncoding("", self.filename),
"registry": self.registry,
}
try:
execfile(self.filename, namespace, namespace)
except OSError as e:
if e.errno == 2: # file not found
request.setResponseCode(http.NOT_FOUND)
request.write(resource.NoResource("File not found.").render(request))
except BaseException:
io = StringIO()
traceback.print_exc(file=io)
output = util._PRE(io.getvalue())
output = output.encode("utf8")
request.write(output)
request.finish()
return server.NOT_DONE_YET