okay. so the config's cleaned up, and we now create a sparse example config file.

utils/he_ipv6/config.py

@@ -1,53 +1,71 @@
 import collections
 import copy
-import ipaddress
 import os
 import re
 ##
-import netaddr
 import requests
 import requests.auth
 from lxml import etree
-from pyroute2 import IPRoute
 ##
 from . import tunnel
 
 
 def create_default_cfg():
     # Create a stripped sample config.
-    nsmap = {None: 'https://tunnelbroker.net/',
-             'xsi': 'http://www.w3.org/2001/XMLSchema-instance'}
-    attr_qname = etree.QName('http://www.w3.org/2001/XMLSchema-instance', 'schemaLocation')
-    schema_url = 'http://schema.xml.r00t2.io/projects/he_ipv6.xsd'
-    schema_loc = '{0} {1}'.format(nsmap[None], schema_url)
-    xml = etree.Element('heIPv6',
-                        {attr_qname: schema_loc},
-                        nsmap = nsmap)
-    xml.append(etree.Comment(('See example.tunnelbroker.xml for an extensively commented sample config.')))
-    creds = etree.SubElement(xml, 'creds')
-    creds.append(etree.Comment(('Your tunnelbroker.net *login*. You can specify multiple credentials via multiple '
-                                '"cred" items. The "id" attribute is up to you but it must be unique.')))
-    cred = etree.SubElement(creds, 'cred')
-    cred.attrib['id'] = ''
-    user = etree.SubElement(cred, 'user')
-    user.text = ''
-    password = etree.SubElement(cred, 'password')
-    password.text = ''
-    tunnels = etree.SubElement(xml, 'tunnels')
-    tunnels.append(etree.Comment(('You can have define multiple tunnels via multiple "tunnel" items. You should most '
-                                  'likely only run one at a time.')))
-    tunnel = etree.SubElement(tunnels, 'tunnel')
-    tunnel.append(etree.Comment(('The "id" attribute should match the id number of a tunnel on your tunnelbroker.net '
-                                 'account. The "creds" attribute references a cred item id attribute.')))
-    tunnel.attrib['id'] = ''
-    tunnel.attrib['creds'] = ''
-    ukey = etree.SubElement(tunnel, '')
-    return (etree.tostring(xml,
-                           encoding = 'UTF-8',
-                           xml_declaration = True,
-                           pretty_print = True,
-                           with_tail = True,
-                           with_comments = True))
+    ws_re = re.compile(r'^\s*$')
+    cur_dir = os.path.dirname(os.path.abspath(os.path.expanduser(__file__)))
+    xtbxml = os.path.join(cur_dir, 'example.tunnelbroker.xml')
+    with open(xtbxml, 'rb') as fh:
+        xml = etree.fromstring(fh.read())
+    # Create a stripped sample config.
+    # First we strip comments (and fix the ensuing whitespace).
+    # etree has a .canonicalize(), but it chokes on a default namespace.
+    # https://bugs.launchpad.net/lxml/+bug/1869455
+    # So everything we do is kind of a hack.
+    # for c in xml.xpath("//comment()"):
+    #    parent = c.getparent()
+    #    parent.remove(c)
+    xmlstr = etree.tostring(xml, with_comments = False, method = 'c14n', pretty_print = True).decode('utf-8')
+    newstr = []
+    for line in xmlstr.splitlines():
+        r = ws_re.search(line)
+        if not r:
+            newstr.append(line.strip())
+    xml = etree.fromstring(''.join(newstr).encode('utf-8'))
+    # Remove text and attr text.
+    xpathq = "descendant-or-self::*[namespace-uri()!='']"
+    for e in xml.xpath(xpathq):
+        if e.tag == '{{{0}}}heIPv6'.format(xml.nsmap[None]):
+            continue
+        if e.text is not None and e.text.strip() != '':
+            e.text = ''
+        for k, v in e.attrib.items():
+            if v is not None:
+                e.attrib[k] = ''
+    # Remove multiple children of same type to simplify.
+    for e in xml.xpath(xpathq):
+        if e.tag == '{{{0}}}heIPv6'.format(xml.nsmap[None]):
+            continue
+        parent = e.getparent()
+        try:
+            for idx, child in enumerate(parent.findall(e.tag)):
+                if idx == 0:
+                    continue
+                parent.remove(child)
+        except AttributeError:
+            pass
+    # And add a comment pointing them to the fully commented config.
+    xml.insert(0, etree.Comment(('\n  Please reference the fully commented example.tunnelbroker.xml found either '
+                                 'at:\n  '
+                                 '  * {0}\n    * https://git.square-r00t.net/RouterBox/tree/utils/he_ipv6/'
+                                 'example.tunnelbroker.xml\n  and then configure this according to those '
+                                 'instructions.\n  ').format(xtbxml)))
+    return(etree.tostring(xml,
+                          pretty_print = True,
+                          with_comments = True,
+                          with_tail = True,
+                          encoding = 'UTF-8',
+                          xml_declaration = True))
 
 
 class Credential(object):
@@ -189,7 +207,10 @@ class Config(BaseConfig):
     def __init__(self, xml_path, *args, **kwargs):
         self.xml_path = os.path.abspath(os.path.expanduser(xml_path))
         if not os.path.isfile(self.xml_path):
-            raise ValueError('xml_path does not exist')
+            with open(self.xml_path, 'wb') as fh:
+                fh.write(create_default_cfg())
+            raise ValueError('xml_path does not exist; '
+                             'a sample configuration has been generated (be sure to configure it)')
         else:
             with open(xml_path, 'rb') as fh:
                 raw_xml = fh.read()