python: Added a simple function for doing directory-local "imports".

[ashd.git] / python / ashd / wsgidir.py

diff --git a/python/ashd/wsgidir.py b/python/ashd/wsgidir.py
index 5711ee6..1fc66f9 100644 (file)
--- a/python/ashd/wsgidir.py
+++ b/python/ashd/wsgidir.py
@@ -33,11 +33,13 @@ argument `.fpy=my.module.foohandler' can be given to pass requests for
 functions, you may want to use the getmod() function in this module.
 """
 
-import os, threading, types
+import sys, os, threading, types, logging, getopt
 import wsgiutil
 
 __all__ = ["application", "wmain", "getmod", "cachedmod", "chain"]
 
+log = logging.getLogger("wsgidir")
+
 class cachedmod(object):
     """Cache entry for modules loaded by getmod()
 
@@ -87,13 +89,13 @@ def getmod(path):
         if path in modcache:
             entry = modcache[path]
         else:
-            entry = cachedmod()
+            entry = [threading.Lock(), None]
             modcache[path] = entry
     finally:
         cachelock.release()
-    entry.lock.acquire()
+    entry[0].acquire()
     try:
-        if entry.mod is None or sb.st_mtime > entry.mtime:
+        if entry[1] is None or sb.st_mtime > entry[1].mtime:
             f = open(path, "r")
             try:
                 text = f.read()
@@ -103,11 +105,31 @@ def getmod(path):
             mod = types.ModuleType(mangle(path))
             mod.__file__ = path
             exec code in mod.__dict__
-            entry.mod = mod
-            entry.mtime = sb.st_mtime
-        return entry
+            entry[1] = cachedmod(mod, sb.st_mtime)
+        return entry[1]
     finally:
-        entry.lock.release()
+        entry[0].release()
+
+def importlocal(filename):
+    import inspect
+    cf = inspect.currentframe()
+    if cf is None: raise ImportError("could not get current frame")
+    if cf.f_back is None: raise ImportError("could not get caller frame")
+    cfile = cf.f_back.f_code.co_filename
+    if not os.path.exists(cfile):
+        raise ImportError("caller is not in a proper file")
+    path = os.path.realpath(os.path.join(os.path.dirname(cfile), filename))
+    if '.' not in os.path.basename(path):
+        for ext in [".pyl", ".py"]:
+            if os.path.exists(path + ext):
+                path += ext
+                break
+        else:
+            raise ImportError("could not resolve file: " + filename)
+    else:
+        if not os.path.exists(cfile):
+            raise ImportError("no such file: " + filename)
+    return getmod(path).mod
 
 class handler(object):
     def __init__(self):
@@ -139,19 +161,27 @@ class handler(object):
 
     def handle(self, env, startreq):
         if not "SCRIPT_FILENAME" in env:
+            log.error("wsgidir called without SCRIPT_FILENAME set")
             return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.")
         path = env["SCRIPT_FILENAME"]
         if not os.access(path, os.R_OK):
+            log.error("%s: not readable" % path)
             return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.")
         if "HTTP_X_ASH_PYTHON_HANDLER" in env:
-            handler = self.resolve(env["HTTP_X_ASH_PYTHON_HANDLER"])
+            try:
+                handler = self.resolve(env["HTTP_X_ASH_PYTHON_HANDLER"])
+            except Exception:
+                log.error("could not load handler %s" % env["HTTP_X_ASH_PYTHON_HANDLER"], exc_info=sys.exc_info())
+                return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.")
         else:
             base = os.path.basename(path)
             p = base.rfind('.')
             if p < 0:
+                log.error("wsgidir called with neither X-Ash-Python-Handler nor a file extension: %s" % path)
                 return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.")
             ext = base[p + 1:]
             if not ext in self.exts:
+                log.error("unregistered file extension: %s" % ext)
                 return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "The server is erroneously configured.")
             handler = self.exts[ext]
         return handler(env, startreq)
@@ -162,12 +192,20 @@ def wmain(*argv):
     Returns the `application' function. If any arguments are given,
     they are parsed according to the module documentation.
     """
-    ret = handler()
-    for arg in argv:
+    hnd = handler()
+    ret = hnd.handle
+
+    opts, args = getopt.getopt(argv, "V")
+    for o, a in opts:
+        if o == "-V":
+            import wsgiref.validate
+            ret = wsgiref.validate.validator(ret)
+
+    for arg in args:
         if arg[0] == '.':
             p = arg.index('=')
-            ret.addext(arg[1:p], arg[p + 1:])
-    return ret.handle
+            hnd.addext(arg[1:p], arg[p + 1:])
+    return ret
 
 def chain(env, startreq):
     """Chain-loading WSGI handler
@@ -185,7 +223,11 @@ def chain(env, startreq):
     object.
     """
     path = env["SCRIPT_FILENAME"]
-    mod = getmod(path)
+    try:
+        mod = getmod(path)
+    except Exception:
+        log.error("Exception occurred when loading %s" % path, exc_info=sys.exc_info())
+        return wsgiutil.simpleerror(env, startreq, 500, "Internal Error", "Could not load WSGI handler.")
     entry = None
     if mod is not None:
         mod.lock.acquire()