---
yum/failover.py | 82 +++++++++++++++++++++++++++++++++++++++++--------------
1 files changed, 61 insertions(+), 21 deletions(-)
diff --git a/yum/failover.py b/yum/failover.py
index bca9651..00c17ad 100644
--- a/yum/failover.py
+++ b/yum/failover.py
@@ -19,51 +19,80 @@
# worry about calling get_serverurl() and server_failed() and these classes
will
# figure out which URL to cough up based on the failover method.
+"""Classes for handling failovers for server URLs."""
+
import random
class baseFailOverMethod:
-
+ """A base class to provide a failover to switch to a new server if
+ the current one fails.
+ """
def __init__(self, repo):
self.repo = repo
self.failures = 0
def get_serverurl(self, i=None):
- """Returns a serverurl based on this failover method or None
- if complete failure. If i is given it is a direct index
- to pull a server URL from instead of using the failures
- counter."""
+ """Return a server URL based on this failover method, or None
+ if there is a complete failure. This method should always be
+ used to translate an index into a URL, as this object may
+ change how indexes map.
+
+ :param i: if given, this is the index of the server URL to
+ return, instead of using the failures counter
+ :return: the next server URL
+ """
return None
def server_failed(self):
- "Tells the failover method that the current server is failed."
+ """Notify the failover method that the current server has
+ failed.
+ """
self.failures = self.failures + 1
def reset(self, i=0):
- "Reset the failures counter to a given index."
+ """Reset the failures counter to the given index.
+
+ :param i: the index to reset the failures counter to
+ """
self.failures = i
def get_index(self):
- """Returns the current number of failures which is also the
- index into the list this object represents. ger_serverurl()
- should always be used to translate an index into a URL
- as this object may change how indexs map. (See RoundRobin)"""
+ """Return the current number of failures, which is also the
+ current index into the list of URLs that this object
+ represents. :fun:`get_serverurl` should always be used to
+ translate an index into a URL, as this object may change how
+ indexes map.
+ :return: the current number of failures, which is also the
+ current index
+ """
return self.failures
def len(self):
- """Returns the how many URLs we've got to cycle through."""
+ """Return the total number of URLs available to cycle through
+ in this object.
+ :return: the total number of URLs available
+ """
return len(self.repo.urls)
class priority(baseFailOverMethod):
-
- """Chooses server based on the first success in the list."""
-
+ """A class to provide a failover to switch to a new server
+ if the current one fails. This classes chooses the next server
+ based on the first success in the list of servers.
+ """
def get_serverurl(self, i=None):
- "Returns a serverurl based on this failover method or None if complete
failure."
-
+ """Return the next successful server URL in the list, or None
+ if there is a complete failure. This method should always be
+ used to translate an index into a URL, as this object may
+ change how indexes map.
+
+ :param i: if given, this is the index of the server URL to
+ return, instead of using the failures counter
+ :return: the next server URL
+ """
if i == None:
index = self.failures
else:
@@ -77,17 +106,28 @@ class priority(baseFailOverMethod):
class roundRobin(baseFailOverMethod):
-
- """Chooses server based on a round robin."""
-
+ """A class to provide a failover to switch to a new server
+ if the current one fails. When an object of this class is
+ created, it selects a random place in the list of URLs to begin
+ with, then each time :func:`get_serveurl` is called, the next URL
+ in the list is returned, cycling back to the beginning of the list
+ after the end is reached.
+ """
def __init__(self, repo):
baseFailOverMethod.__init__(self, repo)
random.seed()
self.offset = random.randint(0, 37)
def get_serverurl(self, i=None):
- "Returns a serverurl based on this failover method or None if complete
failure."
+ """Return the next successful server URL in the list, using
+ the round robin scheme, or None if there is a complete
+ failure. This method should always be used to translate an
+ index into a URL, as this object may change how indexes map.
+ :param i: if given, this is the index of the server URL to
+ return, instead of using the failures counter
+ :return: the next server URL
+ """
if i == None:
index = self.failures
else:
--
1.7.5.4
_______________________________________________
Yum-devel mailing list
Yum-devel@lists.baseurl.org
http://lists.baseurl.org/mailman/listinfo/yum-devel
