Classify errors and advance URL index according to the error code.
In CL https://gerrit.chromium.org/gerrit/39638, we always incremented
the URL index irrespective of the error code. That would cause the first
URL to be given up too quickly in favor of the second one even for
transient errors such as when user closes a lid and reopens after some
time.
The right behavior in this case is to just count those failures towards
the URL and only after repeated failures with no progress should we
advance the URL index.
This CL implements this logic and completes the multiple URL-related
work items outlined in the design doc.
BUG=chromium-os:37206
TEST=Tested all uses cases on my ZGB. Added and updated unit tests.
Change-Id: Ida0cfbfeb9bfab732144049d1b27e3b8958bc252
Reviewed-on: https://gerrit.chromium.org/gerrit/39885
Commit-Queue: Jay Srinivasan <jaysri@chromium.org>
Reviewed-by: Jay Srinivasan <jaysri@chromium.org>
Tested-by: Jay Srinivasan <jaysri@chromium.org>
diff --git a/omaha_request_action.h b/omaha_request_action.h
index bc9b4fe..ebd3ed0 100644
--- a/omaha_request_action.h
+++ b/omaha_request_action.h
@@ -37,6 +37,7 @@
size(0),
metadata_size(0),
max_days_to_scatter(0),
+ max_failure_count_per_url(0),
needs_admin(false),
prompt(false) {}
// True iff there is an update to be downloaded.
@@ -59,6 +60,10 @@
off_t size;
off_t metadata_size;
int max_days_to_scatter;
+ // The number of URL-related failures to tolerate before moving on to the
+ // next URL in the current pass. This is a configurable value from the
+ // Omaha Response attribute, if ever we need to fine tune the behavior.
+ int max_failure_count_per_url;
bool needs_admin;
bool prompt;
};
@@ -124,6 +129,12 @@
public:
static const int kNeverPinged = -1;
static const int kPingTimeJump = -2;
+ // We choose this value of 10 as a heuristic for a work day in trying
+ // each URL, assuming we check roughly every 45 mins. This is a good time to
+ // wait - neither too long nor too little - so we don't give up the preferred
+ // URLs that appear earlier in list too quickly before moving on to the
+ // fallback ones.
+ static const int kDefaultMaxFailureCountPerUrl = 10;
// These are the possible outcome upon checking whether we satisfied
// the wall-clock-based-wait.