Refactor connection initialization code.refactor-connection-init

1 files changed, 36 insertions, 25 deletions

diff --git a/kombu/connection.py b/kombu/connection.py
index d74cb80d..fd69500d 100644
--- a/kombu/connection.py
+++ b/kombu/connection.py
@@ -160,7 +160,7 @@ class Connection(object):
                  transport_options=None, login_method=None, uri_prefix=None,
                  heartbeat=0, failover_strategy='round-robin',
                  alternates=None, **kwargs):
-        alt = [] if alternates is None else alternates
+        self.alt = alternates or []
         # have to spell the args out, just to get nice docstrings :(
         params = self._initial_params = {
             'hostname': hostname, 'userid': userid,
@@ -170,22 +170,37 @@ class Connection(object):
             'login_method': login_method, 'heartbeat': heartbeat
         }
 
-        if hostname and not isinstance(hostname, string_t):
-            alt.extend(hostname)
-            hostname = alt[0]
-        if hostname and '://' in hostname:
-            if ';' in hostname:
-                alt.extend(hostname.split(';'))
-                hostname = alt[0]
+        if hostname:
+            hostname = self._parse_alternatives(hostname)
+            self._parse_transport_and_options_from_uri(hostname, transport, params)
+
+        self._init_params(**params)
+
+        # fallback hosts
+        self._initialize_failover_strategy(failover_strategy)
+
+        self.transport_options = transport_options or {}
+
+        if _log_connection:  # pragma: no cover
+            self._logger = True
+
+        if uri_prefix:
+            self.uri_prefix = uri_prefix
+
+        self.declared_entities = set()
+
+    def _parse_transport_and_options_from_uri(self, hostname, transport, params):
+        if '://' in hostname:
             if '+' in hostname[:hostname.index('://')]:
                 # e.g. sqla+mysql://root:masterkey@localhost/
                 params['transport'], params['hostname'] = \
                     hostname.split('+', 1)
                 self.uri_prefix = params['transport']
             else:
+                # Figure out transport from arguments or URI
                 transport = transport or urlparse(hostname).scheme
                 if not get_transport_cls(transport).can_parse_url:
-                    # we must parse the URL
+                    # We must parse the URL
                     url_params = parse_url(hostname)
                     params.update(
                         dictfilter(url_params),
@@ -194,10 +209,18 @@ class Connection(object):
 
                 params['transport'] = transport
 
-        self._init_params(**params)
-
-        # fallback hosts
-        self.alt = alt
+    def _parse_alternatives(self, hostname):
+        if not isinstance(hostname, string_t):
+            # hostname is actually an iterable of hostnames
+            self.alt.extend(hostname)
+            hostname = self.alt[0]
+        elif ';' in hostname:
+            # hostname is a semicolon delimited list of hostnames
+            self.alt.extend(hostname.split(';'))
+            hostname = self.alt[0]
+        return hostname
+
+    def _initialize_failover_strategy(self, failover_strategy):
         # keep text representation for .info
         # only temporary solution as this won't work when
         # passing a custom object (Issue celery/celery#3320).
@@ -208,18 +231,6 @@ class Connection(object):
             self.cycle = self.failover_strategy(self.alt)
             next(self.cycle)  # skip first entry
 
-        if transport_options is None:
-            transport_options = {}
-        self.transport_options = transport_options
-
-        if _log_connection:  # pragma: no cover
-            self._logger = True
-
-        if uri_prefix:
-            self.uri_prefix = uri_prefix
-
-        self.declared_entities = set()
-
     def switch(self, url):
         """Switch connection parameters to use a new URL.