Make MetricsService upload logs through an interface.

components/metrics/metrics_service_client.h

Index: components/metrics/metrics_service_client.h
===================================================================
--- components/metrics/metrics_service_client.h	(revision 272759)
+++ components/metrics/metrics_service_client.h	(working copy)
@@ -9,6 +9,8 @@
 
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
+#include "base/memory/scoped_ptr.h"
+#include "components/metrics/metrics_log_uploader.h"
 #include "components/metrics/proto/system_profile.pb.h"
 
 namespace metrics {
@@ -50,6 +52,15 @@
   // extra histograms that will go in that log. Asynchronous API - the client
   // implementation should call |done_callback| when complete.
   virtual void CollectFinalMetrics(const base::Closure& done_callback) = 0;
+
+  // Creates a MetricsLogUploader for uploading to the specified |server_url|
+  // with the given |mime_type|. When a log upload is finished, the uploader
+  // will call |on_upload_complete| with the response code or with -1 on an
+  // error.
+  virtual scoped_ptr<MetricsLogUploader> CreateUploader(
+      const std::string& server_url,
+      const std::string& mime_type,
+      const base::Callback<void(int)> on_upload_complete) = 0;

[blundell, 2014/05/26 07:56:56]

It seems like all these parameters belong as constructor parameters on
MetricsLogUploader, and the second sentence of the comment on this function
could then move to be a comment on MetricsLogUploader as well.

[Alexei Svitkine (slow), 2014/05/26 20:04:10]

Just to clarify, do you mean changing MetricsLogUploader to no longer be just a
pure virtual interface but instead have a ctor and protected members
server_url_, mime_type_ and on_upload_complete_ that can then be used by its
sub-classes?

I'm okay doing this, just wanted to make sure this is what you're suggesting
since this will involve adding a metrics_log_uploader.cc (and this function
would still take the same params).

[blundell, 2014/05/26 20:22:15]

I was actually just suggesting adding them as parameters to the
MetricsLogUploader constructor, as it seems intuitive to me to have these params
on that constructor (where they can be described in detail in the place where
someone would look when trying to figure out how to implement that interface in
a reasonable way). The extra step that you're suggesting of having them be ivars
of the MetricsLogUploader base class sounds good though.

On 2014/05/26 20:04:10, Alexei Svitkine wrote:

[Alexei Svitkine (slow), 2014/05/27 14:36:40]

Done. I've now added those params/ivars to the base class.

 };
 
 }  // namespace metrics