From: Fredrik Tolf Date: Tue, 13 Dec 2011 05:50:09 +0000 (+0100) Subject: python: Use an X-Ash-Python-Handler added header for dispatching in wsgidir. X-Git-Tag: 0.10~4 X-Git-Url: http://www.dolda2000.com/gitweb/?p=ashd.git;a=commitdiff_plain;h=7ed9b82bf5df75bc49e49c548307ad3a146224f6 python: Use an X-Ash-Python-Handler added header for dispatching in wsgidir. --- diff --git a/python/ashd/wsgidir.py b/python/ashd/wsgidir.py index 77f41fb..ada5282 100644 --- a/python/ashd/wsgidir.py +++ b/python/ashd/wsgidir.py @@ -1,40 +1,36 @@ """WSGI handler for serving chained WSGI modules from physical files -The WSGI handler in this module examines the SCRIPT_FILENAME variable -of the requests it handles -- that is, the physical file corresponding -to the request, as determined by the webserver -- determining what to -do with the request based on the extension of that file. - -By default, it handles files named `.wsgi' by compiling them into -Python modules and using them, in turn, as chained WSGI handlers, but -handlers for other extensions can be installed as well. - -When handling `.wsgi' files, the compiled modules are cached and -reused until the file is modified, in which case the previous module -is discarded and the new file contents are loaded into a new module in -its place. When chaining such modules, an object named `wmain' is -first looked for and called with no arguments if found. The object it -returns is then used as the WSGI application object for that module, -which is reused until the module is reloaded. If `wmain' is not found, -an object named `application' is looked for instead. If found, it is -used directly as the WSGI application object. +The WSGI handler in this module ensures that the SCRIPT_FILENAME +variable is properly set in every request and points out a file that +exists and is readable. It then dispatches the request in one of two +ways: If the header X-Ash-Python-Handler is set in the request, its +value is used as the name of a handler object to dispatch the request +to; otherwise, the file extension of the SCRIPT_FILENAME is used to +determine the handler object. + +The name of a handler object is specified as a string, which is split +along its last constituent dot. The part left of the dot is the name +of a module, which is imported; and the part right of the dot is the +name of an object in that module, which should be a callable adhering +to the WSGI specification. Alternatively, the module part may be +omitted (such that the name is a string with no dots), in which case +the handler object is looked up from this module. + +By default, this module will handle files with the extensions `.wsgi' +or `.wsgi2' using the `chain' handler, which chainloads such files and +runs them as independent WSGI applications. See its documentation for +details. This module itself contains both an `application' and a `wmain' object. If this module is used by ashd-wsgi(1) or scgi-wsgi(1) so that its wmain function is called, arguments can be specified to it to install handlers for other file extensions. Such arguments take the -form `.EXT=MODULE.HANDLER', where EXT is the file extension to be -handled, and the MODULE.HANDLER string is treated by splitting it -along its last constituent dot. The part left of the dot is the name -of a module which is imported, and the part right of the dot is the -name of an object in that module, which should be a callable adhering -to the WSGI specification. When called, this module will have made -sure that the WSGI environment contains the SCRIPT_FILENAME parameter -and that it is properly working. For example, the argument -`.fpy=my.module.foohandler' can be given to pass requests for `.fpy' -files to the function `foohandler' in the module `my.module' (which -must, of course, be importable). When writing such handler functions, -you will probably want to use the getmod() function in this module. +form `.EXT=HANDLER', where EXT is the file extension to be handled, +and HANDLER is a handler name, as described above. For example, the +argument `.fpy=my.module.foohandler' can be given to pass requests for +`.fpy' files to the function `foohandler' in the module `my.module' +(which must, of course, be importable). When writing such handler +functions, you may want to use the getmod() function in this module. """ import os, threading, types @@ -145,14 +141,20 @@ class handler(object): if not "SCRIPT_FILENAME" in env: return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") path = env["SCRIPT_FILENAME"] - base = os.path.basename(path) - p = base.rfind('.') - if p < 0 or not os.access(path, os.R_OK): + if not os.access(path, os.R_OK): return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") - ext = base[p + 1:] - if not ext in self.exts: - return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") - return(self.exts[ext](env, startreq)) + if "HTTP_X_ASH_PYTHON_HANDLER" in env: + handler = self.resolve(env["HTTP_X_ASH_PYTHON_HANDLER"]) + else: + base = os.path.basename(path) + p = base.rfind('.') + if p < 0: + return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") + ext = base[p + 1:] + if not ext in self.exts: + return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") + handler = self.exts[ext] + return handler(env, startreq) def wmain(*argv): """Main function for ashd(7)-compatible WSGI handlers @@ -168,6 +170,20 @@ def wmain(*argv): return ret.handle def chain(env, startreq): + """Chain-loading WSGI handler + + This handler loads requested files, compiles them and loads them + into their own modules. The compiled modules are cached and reused + until the file is modified, in which case the previous module is + discarded and the new file contents are loaded into a new module + in its place. When chaining such modules, an object named `wmain' + is first looked for and called with no arguments if found. The + object it returns is then used as the WSGI application object for + that module, which is reused until the module is reloaded. If + `wmain' is not found, an object named `application' is looked for + instead. If found, it is used directly as the WSGI application + object. + """ path = env["SCRIPT_FILENAME"] mod = getmod(path) entry = None diff --git a/python3/ashd/wsgidir.py b/python3/ashd/wsgidir.py index 5761761..e7c168c 100644 --- a/python3/ashd/wsgidir.py +++ b/python3/ashd/wsgidir.py @@ -1,40 +1,36 @@ """WSGI handler for serving chained WSGI modules from physical files -The WSGI handler in this module examines the SCRIPT_FILENAME variable -of the requests it handles -- that is, the physical file corresponding -to the request, as determined by the webserver -- determining what to -do with the request based on the extension of that file. - -By default, it handles files named `.wsgi' by compiling them into -Python modules and using them, in turn, as chained WSGI handlers, but -handlers for other extensions can be installed as well. - -When handling `.wsgi' files, the compiled modules are cached and -reused until the file is modified, in which case the previous module -is discarded and the new file contents are loaded into a new module in -its place. When chaining such modules, an object named `wmain' is -first looked for and called with no arguments if found. The object it -returns is then used as the WSGI application object for that module, -which is reused until the module is reloaded. If `wmain' is not found, -an object named `application' is looked for instead. If found, it is -used directly as the WSGI application object. +The WSGI handler in this module ensures that the SCRIPT_FILENAME +variable is properly set in every request and points out a file that +exists and is readable. It then dispatches the request in one of two +ways: If the header X-Ash-Python-Handler is set in the request, its +value is used as the name of a handler object to dispatch the request +to; otherwise, the file extension of the SCRIPT_FILENAME is used to +determine the handler object. + +The name of a handler object is specified as a string, which is split +along its last constituent dot. The part left of the dot is the name +of a module, which is imported; and the part right of the dot is the +name of an object in that module, which should be a callable adhering +to the WSGI specification. Alternatively, the module part may be +omitted (such that the name is a string with no dots), in which case +the handler object is looked up from this module. + +By default, this module will handle files with the extensions `.wsgi' +or `.wsgi2' using the `chain' handler, which chainloads such files and +runs them as independent WSGI applications. See its documentation for +details. This module itself contains both an `application' and a `wmain' object. If this module is used by ashd-wsgi(1) or scgi-wsgi(1) so that its wmain function is called, arguments can be specified to it to install handlers for other file extensions. Such arguments take the -form `.EXT=MODULE.HANDLER', where EXT is the file extension to be -handled, and the MODULE.HANDLER string is treated by splitting it -along its last constituent dot. The part left of the dot is the name -of a module which is imported, and the part right of the dot is the -name of an object in that module, which should be a callable adhering -to the WSGI specification. When called, this module will have made -sure that the WSGI environment contains the SCRIPT_FILENAME parameter -and that it is properly working. For example, the argument -`.fpy=my.module.foohandler' can be given to pass requests for `.fpy' -files to the function `foohandler' in the module `my.module' (which -must, of course, be importable). When writing such handler functions, -you will probably want to use the getmod() function in this module. +form `.EXT=HANDLER', where EXT is the file extension to be handled, +and HANDLER is a handler name, as described above. For example, the +argument `.fpy=my.module.foohandler' can be given to pass requests for +`.fpy' files to the function `foohandler' in the module `my.module' +(which must, of course, be importable). When writing such handler +functions, you may want to use the getmod() function in this module. """ import os, threading, types, importlib @@ -133,14 +129,20 @@ class handler(object): if not "SCRIPT_FILENAME" in env: return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") path = env["SCRIPT_FILENAME"] - base = os.path.basename(path) - p = base.rfind('.') - if p < 0 or not os.access(path, os.R_OK): + if not os.access(path, os.R_OK): return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") - ext = base[p + 1:] - if not ext in self.exts: - return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") - return(self.exts[ext](env, startreq)) + if "HTTP_X_ASH_PYTHON_HANDLER" in env: + handler = self.resolve(env["HTTP_X_ASH_PYTHON_HANDLER"]) + else: + base = os.path.basename(path) + p = base.rfind('.') + if p < 0: + return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") + ext = base[p + 1:] + if not ext in self.exts: + return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.") + handler = self.exts[ext] + return handler(env, startreq) def wmain(*argv): """Main function for ashd(7)-compatible WSGI handlers @@ -156,6 +158,20 @@ def wmain(*argv): return ret.handle def chain(env, startreq): + """Chain-loading WSGI handler + + This handler loads requested files, compiles them and loads them + into their own modules. The compiled modules are cached and reused + until the file is modified, in which case the previous module is + discarded and the new file contents are loaded into a new module + in its place. When chaining such modules, an object named `wmain' + is first looked for and called with no arguments if found. The + object it returns is then used as the WSGI application object for + that module, which is reused until the module is reloaded. If + `wmain' is not found, an object named `application' is looked for + instead. If found, it is used directly as the WSGI application + object. + """ path = env["SCRIPT_FILENAME"] mod = getmod(path) entry = None