r4909 - trunk/sage/python/sage

Author: tmckay
Date: 2011-08-05 20:49:12 +0000 (Fri, 05 Aug 2011)
New Revision: 4909

Modified:
   trunk/sage/python/sage/util.py
Log:
Change url parsing routines to use regular expressions and allow path, etc.


Modified: trunk/sage/python/sage/util.py
===================================================================
--- trunk/sage/python/sage/util.py	2011-08-05 18:59:48 UTC (rev 4908)
+++ trunk/sage/python/sage/util.py	2011-08-05 20:49:12 UTC (rev 4909)
@@ -1,5 +1,8 @@
 from time import time, sleep
 from threading import Thread, Lock
+import re
+import copy
+import string
 
 class MethodResult(object):
     '''
@@ -201,78 +204,81 @@
         '''
         raise Exception("Not implemented")
 
-def host_port(hostname):
-    '''
-    Returns a tuple containing 'host' and 'port' strings from hostname. 
+class sage_URL(object):
+    def __init__(self, scheme, user, password, host, port, path):
+        self.scheme = scheme
+        self.user = user
+        self.password = password
+        self.host = host
+        self.port = port
+        self.path = path
 
-    Strings are split at the first colon to produce host and port strings.
-    A string containing only digits will result in a tuple with the host 
-    value set to None and the port value set to the entire string.  A string
-    containing non-digits but no colon will result in a tuple with the port 
-    value set to None and the host value set to the entire string.
-    '''
-    assert type(hostname) in (str, unicode)
-    import string
+    def __repr__(self):
+        return "sage_URL(%r)" % str(self)
 
-    host = None
-    port = None
+    def __str__(self):
+        s = ""
+        if self.scheme:
+            s += "%s://" % self.scheme
+        if self.user:
+            s += self.user
+            if self.password:
+                s += "/%s" % self.password
+            s += "@"
+        s += self.host
+        if self.port:
+            s += ":%s" % self.port
+        if self.path:
+            s += "/%s" % self.path 
+        return s
 
-    info = string.split(hostname, ":", maxsplit=1)
-    if len(info) == 1:
-        # All digits, assume it was just a port number
-        if info[0].isdigit():
-            port = info[0]
-        else:
-            host = info[0]
-    else:
-        host = info[0]
-        port = info[1]
-    return host, port
+def parse_URL(hoststring):
 
-def host_port_list(netlocs, default_port=None):
-    '''
-    Parses a list of network locations and returns
-    a dictionary keyed by host containing sets of ports for each host.
+  RE = re.compile(r"""
+        # [   <scheme>://  ] [    <user>   [   / <password>   ] @]  
<host>   [   :<port>   ] [ <path> ]
+        ^ (?: ([^:/@]+)://)? (?: ([^:/@]+) (?: / ([^:/@]+)   )? @)? ([^@:/]+) (?:
:([0-9]+))? (?: / (.*))?$
+        """, re.X)
 
-    Uses sage.util.host_port() to parse each item in the list.
+  scheme = user = password = host = port = path = None
+  match = RE.match(hoststring)
+  if match is not None:
+      scheme, user, password, host, port, path = match.groups()
+  return sage_URL(scheme, user, password, host, port, path)
 
-    netlocs -- comma-separated list of network locations.  A network location
-    may have one of the following forms: 'host', 'host:port', or
'port'.
-    If the 'port' form is used, the 'host' value is assumed to be the
last
-    host encountered in the list or "localhost" if no host has been
-    encountered.  If the 'host' form is used, an entry for the host is made
-    in the dictionary with an port list.
+def host_list(netlocs, default_scheme=None, default_port=None, default_path=None):
+    tokens = string.split(netlocs, ",")
 
-    default_port -- port value for hosts in the dictionary which contain an 
-    empty port set after 'netlocs' is fully parsed.  Ignored if equal to None.
-    '''
-    assert type(netlocs) in (str, unicode)
-    import string
+    hosts = dict()
+    last_url = None
+    last_port_set = False
 
-    # A dictionary of sets of ports keyed
-    # by hostname
-    hosts = dict()
-    tokens = string.split(netlocs, ",")
-    lasthost = "localhost"
-    for name in tokens:
-        host, port = host_port(string.strip(name))
-        if host is None:
-            host = lasthost
+    for loc in tokens:
+        url = None
+        loc = string.strip(loc)
+        if loc.isdigit():
+            # Allow just a port number to be specified if the previous
+            # url explicitly set a port.  Shorthand for port list.
+            # Copy all information from the previous token except port.
+            if last_url is not None and last_port_set:
+                url = copy.copy(last_url)
+                url.port = loc
         else:
-            lasthost = host
-        if host not in hosts:
-            if port is None:
-                hosts[host] = set()
+            url = parse_URL(loc)
+            if url.scheme is None:
+                url.scheme = default_scheme
+            if url.path is None:
+                url.path = default_path
+            if url.port is None:
+                url.port = str(default_port)
+                last_port_set = False
             else:
-                hosts[host] = set([port])
-        elif port is not None:
-            hosts[host].add(port)
+                last_port_set = True
+        last_url = url
+        if url is not None and url.host is not None and url.port is not None:
+            if url.host not in hosts:
+                hosts[url.host] = list()
+            hosts[url.host].append(url)
+                
+    return hosts
 
-    # Fill in default ports for hosts with no
-    # ports assigned
-    if default_port is not None:
-        for host, ports in hosts.iteritems():
-            if len(ports) == 0:
-                ports.add(default_port)
-    return hosts