I am rewriting wsgi.py in nevow. I face some problems with the nevow url module. [snip]

Herewith I am attaching the current wsgi.py --- # TODO: # 1. make exception renderer work import os, sys, socket, math, time import cgi # for FieldStorage import types from urllib import unquote, quote from nevow import context, flat, inevow, util from nevow import __version__ as nevowversion def log(msg): print >>sys.stderr, "WSGI: {%s}" % str(msg) errorMarker = object() class NevowWSGISite(object): def __init__(self, request, resource): self.request = request self.resource = resource self.context = context.SiteContext() def remember(self, obj, inter=None): self.context.remember(obj, inter) def getPageContextForRequestContext(self, ctx): """Retrieve a resource from this site for a particular request. The resource will be wrapped in a PageContext which keeps track of how the resource was located. """ path = inevow.IRemainingSegments(ctx) res = inevow.IResource(self.resource) pageContext = context.PageContext(tag=res, parent=ctx) return self.handleSegment( res.locateChild(pageContext, path), ctx.tag, path, pageContext) def handleSegment(self, result, request, path, pageContext): if result is errorMarker: return errorMarker newres, newpath = result # If the child resource is None then display a 404 page if newres is None: from nevow.rend import FourOhFour return context.PageContext(tag=FourOhFour(), parent=pageContext) # If we got a deferred then we need to call back later, once the # child is actually available. #if isinstance(newres, defer.Deferred): # return newres.addCallback( # lambda actualRes: self.handleSegment( # (actualRes, newpath), request, path, pageContext)) newres = inevow.IResource(newres, persist=True) if newres is pageContext.tag: assert not newpath is path, "URL traversal cycle detected when attempting to locateChild %r from resource %r." % (path, pageContext.tag) assert len(newpath) < len(path), "Infinite loop impending..." ## We found a Resource... update the request.prepath and postpath for x in xrange(len(path) - len(newpath)): request.prepath.append(request.postpath.pop(0)) ## Create a context object to represent this new resource ctx = context.PageContext(tag=newres, parent=pageContext) ctx.remember(tuple(request.prepath), inevow.ICurrentSegments) ctx.remember(tuple(request.postpath), inevow.IRemainingSegments) res = newres path = newpath if not path: return ctx return self.handleSegment( res.locateChild(ctx, path), request, path, ctx) def createWSGIApplication(page, rootURL=None): """Given a Page instance, return a WSGI callable. `rootURL` - URL to be remembered as root """ page.flattenFactory = flat.iterflatten siteCtx = context.SiteContext(tag=None) def application(environ, start_response): request = WSGIRequest(environ, start_response) if rootURL: request.rememberRootURL(rootURL) site = NevowWSGISite(request, page) request.site = site result = request.process() if not request.headersSent: request.write('') # send headers now if isinstance(result, str): yield result elif isinstance(result, util.Deferred): ## So we can use the wsgi module if twisted is installed ## TODO use render synchronously instead maybe? I'm pretty ## sure after the application callable returns, the request ## is "closed". Investigate with the latest wsgi spec and ## some implementations. #raise 'PH' + str(dir(result)) + '{{%s}}' % str(result.result) yield result.result else: for x in result: yield x return application # TODO: convert interface comments class WSGIRequest(object): __implements__ = inevow.IRequest, """A HTTP request. Subclasses should override the process() method to determine how the request will be processed. @ivar method: The HTTP method that was used. @ivar uri: The full URI that was requested (includes arguments). @ivar path: The path only (arguments not included). @ivar args: All of the arguments, including URL and POST arguments. @type args: A mapping of strings (the argument names) to lists of values. i.e., ?foo=bar&foo=lf._parseQuery(environ.get('QUERY_STRING', '')) for k,v in environ.items(): if k.startswith('HTTP_'): self.received_headers[k[5:].lower()] = v self.setResponseCode("200")baz&quux=spam results in {'foo': ['bar', 'baz'], 'quux': ['spam']}. @ivar received_headers: All received headers """ def __init__(self, environ, start_response): self.environ = environ self.start_response = start_response self.outgoingHeaders = [] self.received_headers = {} self.lastModified = None self.etag = None self.method = environ.get('REQUEST_METHOD', 'GET') self.args = self._parseQuery(environ.get('QUERY_STRING', '')) self.host = (self.environ['REMOTE_ADDR'], int(self.environ['REMOTE_PORT'])) for k,v in environ.items(): if k.startswith('HTTP_'): self.received_headers[k[5:].lower()] = v self.setResponseCode("200") self.headersSent = False self.appRootURL = None self.deferred = util.Deferred() def process(self): """When a form is POSTed, we create a cgi.FieldStorage instance using the data posted, and set it as the request.fields attribute. This way, we can get at information about filenames and mime-types of files that were posted.""" if self.method == 'POST': self.fields = cgi.FieldStorage( self.environ['wsgi.input'], self.received_headers, environ={'REQUEST_METHOD': 'POST'}) # set various default headers self.setHeader('server', nevowversion) year, month, day, hh, mm, ss, wd, y, z = time.gmtime(time.time()) # HTTP date string format s = "%s, %02d %3s %4d %02d:%02d:%02d GMT" % ( weekdayname[wd], day, monthname[month], year, hh, mm, ss) self.setHeader('date', s) self.setHeader('content-type', 'text/html; charset=UTF-8') # Resource Identification self.prepath = [] self.postpath = map(unquote, self.path[1:].split('/')) self.sitepath = [] requestContext = context.RequestContext( parent=self.site.context, tag=self) requestContext.remember( (), inevow.ICurrentSegments) requestContext.remember(tuple(self.postpath), inevow.IRemainingSegments) pageContext = self.site.getPageContextForRequestContext(requestContext) return self.gotPageContext(pageContext) def gotPageContext(self, pageContext): if pageContext is errorMarker: return None html = pageContext.tag.renderHTTP(pageContext) if isinstance(html, util.Deferred): # This is a deferred object # Let us return it synchronously # (wsgi has nothing to do with sync, async) # XXX: Is this correct? html = html.result # FIXME: I dunno what to do when a generator comes .. # Perhaps, it may generate non-str? I dunno if type(html) is types.GeneratorType: html = ''.join(list(html)) if html is errorMarker: ## Error webpage has already been rendered and finish called pass elif isinstance(html, str): return html else: res = inevow.IResource(html, None) if res is not None: pageContext = context.PageContext(tag=res, parent=pageContext) return self.gotPageContext(pageContext) else: # import traceback; traceback.print_stack() print >>sys.stderr, "html is not a string: %s on %s" % (str(html), pageContext.tag) return html def _parseQuery(self, qs): d = {} items = [s2 for s1 in qs.split("&") for s2 in s1.split(";")] for item in items: try: k, v = item.split("=", 1) except ValueError: # no strict parsing continue k = unquote(k.replace("+", " ")) v = unquote(v.replace("+", " ")) if k in d: d[k].append(v) else: d[k] = [v] return d def _getPath(self): pth = self.environ.get('PATH_INFO', '') if not pth: pth = '/' return pth path = property(_getPath) def _getURI(self): query = self.environ.get('QUERY_STRING', '') if query: query = '?' + query return self.path + query uri = property(_getURI) # Methods for received request def getHeader(self, key): """Get a header that was sent from the network. """ return self.received_headers.get(key.lower()) def getCookie(self, key): """Get a cookie that was sent from the network. """ def getAllHeaders(self): """Return dictionary of all headers the request received.""" return self.received_headers def getRequestHostname(self): """Get the hostname that the user passed in to the request. This will either use the Host: header (if it is available) or the host we are listening on if the header is unavailable. """ return (self.getHeader('host') or socket.gethostbyaddr(self.getHost()[1])[0] ).split(':')[0] def getHost(self): """Get my originally requesting transport's host. Don't rely on the 'transport' attribute, since Request objects may be copied remotely. For information on this method's return value, see twisted.internet.tcp.Port. """ def getClientIP(self): return self.environ.get('REMOTE_ADDR', None) def getClient(self): pass def getUser(self): pass def getPassword(self): pass def isSecure(self): return self.environ['wsgi.url_scheme'] == 'https' def getSession(self, sessionInterface = None): pass def URLPath(self): from nevow import url return url.URL.fromString(self.appRootURL+self.uri) def prePathURL(self): if self.isSecure(): default = 443 else: default = 80 # TODO: use getHost().port after getHost is implemented port = default if port == default: hostport = '' else: hostport = ':%d' % port # FIXME: This hack, until url module is fixed to support RootURLs # Or is this the right way to do? if self.appRootURL: return quote('%s%s' % (self.appRootURL, '/'.join(self.prepath)), '/:') return quote('http%s://%s%s/%s' % ( self.isSecure() and 's' or '', self.getRequestHostname(), hostport, '/'.join(self.prepath)), '/:') def rememberRootURL(self, url=None): # result = p.renderHTTP(pctx) """ Remember the currently-processed part of the URL for later recalling. """ if url is None: raise NotImplementedError self.appRootURL = url def getRootURL(self): """ Get a previously-remembered URL. """ return self.appRootURL # Methods for outgoing request def finish(self): """We are finished writing data.""" def write(self, data): """ Write some data as a result of an HTTP request. The first time this is called, it writes out response data. """ if self.headersSent: self._write(data) return headerkeys = [k for k,v in self.outgoingHeaders] self._write = self.start_response( self.responseCode, self.outgoingHeaders, None) self.headersSent = True if data: self._write(data) def addCookie(self, k, v, expires=None, domain=None, path=None, max_age=None, comment=None, secure=None): """Set an outgoing HTTP cookie. In general, you should consider using sessions instead of cookies, see twisted.web.server.Request.getSession and the twisted.web.server.Session class for details. """ def setResponseCode(self, code, message=None): """Set the HTTP response code. """ self.responseCode = '%s %s' % (code, RESPONSES[int(str(code))]) def setHeader(self, header, value): """Set an outgoing HTTP header. """ self.outgoingHeaders.append((header.lower(), value)) def redirect(self, url): """Utility function that does a redirect. The request should have finish() called after this. """ log('REDIRECT to ' + str(url)) self.setResponseCode(str(302)) self.setHeader('location', url) def setLastModified(self, when): """Set the X{Last-Modified} time for the response to this request. If I am called more than once, I ignore attempts to set Last-Modified earlier, only replacing the Last-Modified time if it is to a later value. If I am a conditional request, I may modify my response code to L{NOT_MODIFIED} if appropriate for the time given. @param when: The last time the resource being returned was modified, in seconds since the epoch. @type when: number @return: If I am a X{If-Modified-Since} conditional request and the time given is not newer than the condition, I return L{http.CACHED<CACHED>} to indicate that you should write no body. Otherwise, I return a false value. """ # time.time() may be a float, but the HTTP-date strings are # only good for whole seconds. when = long(math.ceil(when)) if (not self.lastModified) or (self.lastModified < when): self.lastModified = when modified_since = self.getHeader('if-modified-since') if modified_since: modified_since = stringToDatetime(modified_since) if modified_since >= when: self.setResponseCode(NOT_MODIFIED) return '' # TODO: return http.CACHED (requires Twisted) return None def setETag(self, etag): """Set an X{entity tag} for the outgoing response. That's \"entity tag\" as in the HTTP/1.1 X{ETag} header, \"used for comparing two or more entities from the same requested resource.\" If I am a conditional request, I may modify my response code to L{NOT_MODIFIED<twisted.protocols.http.NOT_MODIFIED>} or L{PRECONDITION_FAILED<twisted.protocols.http.PRECONDITION_FAILED>}, if appropriate for the tag given. @param etag: The entity tag for the resource being returned. @type etag: string @return: If I am a X{If-None-Match} conditional request and the tag matches one in the request, I return L{CACHED<twisted.protocols.http.CACHED>} to indicate that you should write no body. Otherwise, I return a false value. """ if etag: self.etag = etag tags = self.getHeader("if-none-match") if tags: tags = tags.split() if (etag in tags) or ('*' in tags): self.setResponseCode(((self.method in ("HEAD", "GET")) and NOT_MODIFIED) or PRECONDITION_FAILED) return '' # TODO: return http.CACHED (requires Twisted) return None def setHost(self, host, port, ssl=0): """Change the host and port the request thinks it's using. This method is useful for working with reverse HTTP proxies (e.g. both Squid and Apache's mod_proxy can do this), when the address the HTTP client is using is different than the one we're listening on. For example, Apache may be listening on https://www.example.com, and then forwarding requests to http://localhost:8080, but we don't want HTML produced by Twisted to say 'http://localhost:8080', they should say 'https://www.example.com', so we do: >>> request.setHost('www.example.com', 443, ssl=1) This method is experimental. """ # Methods not part of IRequest # producer = None def registerProducer(self, other, _): assert self.producer is None self.producer = other while self.producer is not None: self.producer.resumeProducing() def unregisterProducer(self): self.producer = None def finish(self): self.deferred.callback('') # FIXME: copied from twisted.web.http _CONTINUE = 100 SWITCHING = 101 OK = 200 CREATED = 201 ACCEPTED = 202 NON_AUTHORITATIVE_INFORMATION = 203 NO_CONTENT = 204 RESET_CONTENT = 205 PARTIAL_CONTENT = 206 MULTI_STATUS = 207 MULTIPLE_CHOICE = 300 MOVED_PERMANENTLY = 301 FOUND = 302 SEE_OTHER = 303 NOT_MODIFIED = 304 USE_PROXY = 305 TEMPORARY_REDIRECT = 307 BAD_REQUEST = 400 UNAUTHORIZED = 401 PAYMENT_REQUIRED = 402 FORBIDDEN = 403 NOT_FOUND = 404 NOT_ALLOWED = 405 NOT_ACCEPTABLE = 406 PROXY_AUTH_REQUIRED = 407 REQUEST_TIMEOUT = 408 CONFLICT = 409 GONE = 410 LENGTH_REQUIRED = 411 PRECONDITION_FAILED = 412 REQUEST_ENTITY_TOO_LARGE = 413 REQUEST_URI_TOO_LONG = 414 UNSUPPORTED_MEDIA_TYPE = 415 REQUESTED_RANGE_NOT_SATISFIABLE = 416 EXPECTATION_FAILED = 417 INTERNAL_SERVER_ERROR = 500 NOT_IMPLEMENTED = 501 BAD_GATEWAY = 502 SERVICE_UNAVAILABLE = 503 GATEWAY_TIMEOUT = 504 HTTP_VERSION_NOT_SUPPORTED = 505 INSUFFICIENT_STORAGE_SPACE = 507 NOT_EXTENDED = 510 RESPONSES = { # 100 _CONTINUE: "Continue", SWITCHING: "Switching Protocols", # 200 OK: "OK", CREATED: "Created", ACCEPTED: "Accepted", NON_AUTHORITATIVE_INFORMATION: "Non-Authoritative Information", NO_CONTENT: "No Content", RESET_CONTENT: "Reset Content.", PARTIAL_CONTENT: "Partial Content", MULTI_STATUS: "Multi-Status", # 300 MULTIPLE_CHOICE: "Multiple Choices", MOVED_PERMANENTLY: "Moved Permanently", FOUND: "Found", SEE_OTHER: "See Other", NOT_MODIFIED: "Not Modified", USE_PROXY: "Use Proxy", # 306 not defined?? TEMPORARY_REDIRECT: "Temporary Redirect", # 400 BAD_REQUEST: "Bad Request", UNAUTHORIZED: "Unauthorized", PAYMENT_REQUIRED: "Payment Required", FORBIDDEN: "Forbidden", NOT_FOUND: "Not Found", NOT_ALLOWED: "Method Not Allowed", NOT_ACCEPTABLE: "Not Acceptable", PROXY_AUTH_REQUIRED: "Proxy Authentication Required", REQUEST_TIMEOUT: "Request Time-out", CONFLICT: "Conflict", GONE: "Gone", LENGTH_REQUIRED: "Length Required", PRECONDITION_FAILED: "Precondition Failed", REQUEST_ENTITY_TOO_LARGE: "Request Entity Too Large", REQUEST_URI_TOO_LONG: "Request-URI Too Long", UNSUPPORTED_MEDIA_TYPE: "Unsupported Media Type", REQUESTED_RANGE_NOT_SATISFIABLE: "Requested Range not satisfiable", EXPECTATION_FAILED: "Expectation Failed", # 500 INTERNAL_SERVER_ERROR: "Internal Server Error", NOT_IMPLEMENTED: "Not Implemented", BAD_GATEWAY: "Bad Gateway", SERVICE_UNAVAILABLE: "Service Unavailable", GATEWAY_TIMEOUT: "Gateway Time-out", HTTP_VERSION_NOT_SUPPORTED: "HTTP Version not supported", INSUFFICIENT_STORAGE_SPACE: "Insufficient Storage Space", NOT_EXTENDED: "Not Extended" } weekdayname = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'] monthname = [None, 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'] --- -- Sridhar Ratna - http://srid.bsdnerds.org