syncdaemon: configinterface: add support for regexp based pattern-matching sections

Signed-off-by: Kaushik BV <kaushikbv@gluster.com>
Signed-off-by: Vijay Bellur <vijay@dev.gluster.com>

BUG: 2427 (set a proper default for remote syncdaemon)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=2427

2 files changed, 130 insertions, 38 deletions

diff --git a/xlators/features/marker/utils/syncdaemon/configinterface.py b/xlators/features/marker/utils/syncdaemon/configinterface.py
index 25a2a5268..f0efc1df8 100644
--- a/xlators/features/marker/utils/syncdaemon/configinterface.py
+++ b/xlators/features/marker/utils/syncdaemon/configinterface.py
@@ -3,29 +3,106 @@ try:
 except ImportError:
     # py 3
     import configparser as ConfigParser
+import re
+try:
+    # py 3
+    from urllib import parse as urllib
+except ImportError:
+    import urllib
 
+SECT_ORD = '__section_order__'
 
-DEF_SECT = 'global'
+re_type = type(re.compile(''))
 
 class GConffile(object):
 
     def __init__(self, path, peers):
-        if peers:
-            self.section = 'peers ' + ' '.join(peers)
-        else:
-            self.section = DEF_SECT
+        self.peers = peers
         self.path = path
         self.config = ConfigParser.RawConfigParser()
         self.config.read(path)
 
+    def section(self, rx=False):
+        peers = self.peers
+        if not peers:
+            peers = ['.', '.']
+            rx = True
+        if rx:
+            st = 'peersrx'
+        else:
+            st = 'peers'
+        return ' '.join([st] + [urllib.quote_plus(u) for u in peers])
+
+    @staticmethod
+    def parse_section(section):
+        sl = section.split()
+        st = sl.pop(0)
+        sl = [urllib.unquote_plus(u) for u in sl]
+        if st == 'peersrx':
+            sl = [re.compile(u) for u in sl]
+        return sl
+
+    def ord_sections(self):
+        """Return an ordered list of sections.
+
+        Ordering happens based on the auxiliary
+        SECT_ORD section storing indices for each
+        section added through the config API.
+
+        To not to go corrupt in case of manually
+        written config files, we take care to append
+        also those sections which are not registered
+        in SECT_ORD.
+
+        Needed for python 2.{4,5} where ConfigParser
+        cannot yet order sections/options internally.
+        """
+        so = {}
+        if self.config.has_section(SECT_ORD):
+            so = self.config._sections[SECT_ORD]
+        so2 = {}
+        for k, v in so.items():
+            if k != '__name__':
+                so2[k] = int(v)
+        tv = 0
+        if so2:
+            tv = max(so2.values()) + 1
+        ss = self.config.sections()
+        try:
+            ss.remove(SECT_ORD)
+        except ValueError:
+            pass
+        for s in ss:
+            if s in so.keys():
+                continue
+            so2[s] = tv
+            tv += 1
+        def scmp(x, y):
+            return cmp(*(so2[s] for s in (x, y)))
+        ss.sort(scmp)
+        return ss
+
     def update_to(self, dct):
-        for sect in set([DEF_SECT, self.section]):
-            if self.config.has_section(sect):
-                for k, v in self.config._sections[sect].items():
-                    if k == '__name__':
-                        continue
-                    k = k.replace('-', '_')
-                    dct[k] = v
+        if not self.peers:
+            raise RuntimeError('no peers given, cannot select matching options')
+        def update_from_sect(sect):
+            for k, v in self.config._sections[sect].items():
+                if k == '__name__':
+                    continue
+                k = k.replace('-', '_')
+                dct[k] = v
+        for sect in self.ord_sections():
+            sp = self.parse_section(sect)
+            if isinstance(sp[0], re_type) and len(sp) == len(self.peers):
+                match = True
+                for i in range(len(sp)):
+                    if not sp[i].search(self.peers[i]):
+                        match = False
+                        break
+                if match:
+                    update_from_sect(sect)
+        if self.config.has_section(self.section()):
+            update_from_sect(self.section())
 
     def get(self, opt=None):
         d = {}
@@ -46,14 +123,20 @@ class GConffile(object):
             if f:
                 f.close()
 
-    def set(self, opt, val):
-        if not self.config.has_section(self.section):
-            self.config.add_section(self.section)
-        self.config.set(self.section, opt, val)
+    def set(self, opt, val, rx=False):
+        sect = self.section(rx)
+        if not self.config.has_section(sect):
+            self.config.add_section(sect)
+            # regarding SECT_ORD, cf. ord_sections
+            if not self.config.has_section(SECT_ORD):
+                self.config.add_section(SECT_ORD)
+            self.config.set(SECT_ORD, sect, len(self.config._sections[SECT_ORD]))
+        self.config.set(sect, opt, val)
         self.write()
 
-    def delete(self, opt):
-        if not self.config.has_section(self.section):
+    def delete(self, opt, rx=False):
+        sect = self.section(rx)
+        if not self.config.has_section(sect):
             return
-        if self.config.remove_option(self.section, opt):
+        if self.config.remove_option(sect, opt):
             self.write()
diff --git a/xlators/features/marker/utils/syncdaemon/gsyncd.py b/xlators/features/marker/utils/syncdaemon/gsyncd.py
index b8b92056b..d8166baea 100644
--- a/xlators/features/marker/utils/syncdaemon/gsyncd.py
+++ b/xlators/features/marker/utils/syncdaemon/gsyncd.py
@@ -199,9 +199,14 @@ def main_i():
                                                                                                      a[-1].values.__dict__.update(log_level='DEBUG')))
     op.add_option('--config-get',           metavar='OPT',  type=str, dest='config', action='callback', callback=store_local)
     op.add_option('--config-get-all', dest='config', action='callback', callback=store_local_curry(True))
-    op.add_option('--config-set',           metavar='OPT VAL', type=str, nargs=2, dest='config', action='callback', callback=store_local)
+    op.add_option('--config-set',           metavar='OPT VAL', type=str, nargs=2, dest='config', action='callback',
+                   callback=lambda o, oo, vx, p: store_local(o, oo, (vx[0], vx[1], False), p))
+    op.add_option('--config-set-rx',        metavar='OPT VAL', type=str, nargs=2, dest='config', action='callback',
+                   callback=lambda o, oo, vx, p: store_local(o, oo, (vx[0], vx[1], True), p))
     op.add_option('--config-del',           metavar='OPT',  type=str, dest='config', action='callback', callback=lambda o, oo, vx, p:
-                                                                                                                    store_local(o, oo, (vx, False), p))
+                                                                                                                    store_local(o, oo, (vx, False, False), p))
+    op.add_option('--config-del-rx',        metavar='OPT',  type=str, dest='config', action='callback', callback=lambda o, oo, vx, p:
+                                                                                                                    store_local(o, oo, (vx, False, True), p))
 
     # precedence for sources of values: 1) commandline, 2) cfg file, 3) defaults
     # -- for this to work out we need to tell apart defaults from explicitly set
@@ -209,25 +214,30 @@ def main_i():
     # values container.
     defaults = op.get_default_values()
     opts, args = op.parse_args(values=optparse.Values())
-    if not (len(args) == 2 or (len(args) == 1 and rconf.get('listen')) or (len(args) <= 2 and rconf.get('config'))):
+    confdata = rconf.get('config')
+    if not (len(args) == 2 or (len(args) == 1 and rconf.get('listen')) or (len(args) <= 2 and confdata)):
         sys.stderr.write("error: incorrect number of arguments\n\n")
         sys.stderr.write(op.get_usage() + "\n")
         sys.exit(1)
 
-    local = remote = None
-    if args:
-      local = resource.parse_url(args[0])
-      if len(args) > 1:
-          remote = resource.parse_url(args[1])
-      if not local.can_connect_to(remote):
-          raise RuntimeError("%s cannot work with %s" % (local.path, remote and remote.path))
-    pa = ([], [])
-    canon = [False, True]
-    for x in (local, remote):
-        if x:
-            for i in range(2):
-                pa[i].append(x.get_url(canonical=canon[i]))
-    peers, canon_peers = pa
+    if confdata and isinstance(confdata, tuple) and confdata[2]:
+        # peers are regexen, don't try to parse them
+        canon_peers = args
+    else:
+        local = remote = None
+        if args:
+          local = resource.parse_url(args[0])
+          if len(args) > 1:
+              remote = resource.parse_url(args[1])
+          if not local.can_connect_to(remote):
+              raise RuntimeError("%s cannot work with %s" % (local.path, remote and remote.path))
+        pa = ([], [])
+        canon = [False, True]
+        for x in (local, remote):
+            if x:
+                for i in range(2):
+                    pa[i].append(x.get_url(canonical=canon[i]))
+        peers, canon_peers = pa
     if not 'config_file' in rconf:
         rconf['config_file'] = os.path.join(os.path.dirname(sys.argv[0]), "conf/gsyncd.conf")
         confp = os.path.dirname(sys.argv[0]) + "conf/"
@@ -241,13 +251,12 @@ def main_i():
                 raise
     gcnf = GConffile(rconf['config_file'], canon_peers)
 
-    confdata = rconf.get('config')
     if confdata:
         if isinstance(confdata, tuple):
             if confdata[1]:
                 gcnf.set(*confdata)
             else:
-                gcnf.delete(confdata[0])
+                gcnf.delete(confdata[0], confdata[1])
         else:
             if confdata == True:
                 confdata = None