Merge lp:~submarine/ubuntu-scopes/devhelp-50-results-limit into lp:~submarine/ubuntu-scopes/devhelp

[David Callé]

Limit the number of results to 50.

Limit the number of results to 50.

[James Henstridge (jamesh)]

Is the purpose of this branch to try and improve performance, or just to limit the result count?

While this certainly does limit the search results to 50 hits, it looks like it is still doing approximately the same amount of work (I assume scanning the /usr/share/gtk-doc/html tree and running an XML parser on each .devhelp file is the slow point).

If performance is the issue, then perhaps one of the following would help:

1. make setup_devhelp() a generator, so exiting the loop early will cut the scanning work short.

2. cache the results of setup_devhelp() between searches.

Either way, a linear scan of the keywords found in the .devhelp file seems awfully slow.

[James Henstridge (jamesh)]

review: Needs Information

[David Callé (davidc3)]

Performance is not really the issue, but the fast that it can return up to ~15 000 results in the Dash feels a bit overwhelming when looking for help.

Nevertheless, I will add the suggested improvements to this merge.

[lp:~submarine/ubuntu-scopes/devhelp-50-results-limit]

19. By David Callé on 2013-03-21

Speed up results

[David Callé (davidc3)]

I've added a bit of caching and not querying for one letter searches. The next step will be to improve the quality of results with libcolumbus, but it can land later IMHO.

[James Henstridge (jamesh)]

Sounds good.

review: Approve

[PS Jenkins bot (ps-jenkins)]

review: Approve (continuous-integration)

=== modified file 'src/unity_devhelp_daemon.py'
--- src/unity_devhelp_daemon.py	2013-03-19 22:20:08 +0000
+++ src/unity_devhelp_daemon.py	2013-03-21 10:08:24 +0000
@@ -51,6 +51,7 @@
 
 EXTRA_METADATA = []
 
+CACHE_DEVHELP = None
 
 def setup_devhelp():
     '''
@@ -101,12 +102,22 @@
     Search for help documents matching the search string
     '''
     results = []
-    devhelp = setup_devhelp()
+    if len(search) < 2:
+        return results
+    global CACHE_DEVHELP
+    if not CACHE_DEVHELP:
+        print("Loading results...")
+        devhelp = setup_devhelp()
+        CACHE_DEVHELP = devhelp
+    else:
+        devhelp = CACHE_DEVHELP
     icon_hint = Gio.ThemedIcon.new("text-x-generic").to_string()
     for data in devhelp:
         if os.path.exists("/usr/lib/unity-lens-help/icons/%s.svg" % data[2]):
             icon_hint = "/usr/lib/unity-lens-help/icons/%s.svg" % data[2]
         if search.lower() in data[0].lower():
+            if len(results) >= 50:
+                break
             results.append({'uri': data[0],
                             'icon': icon_hint,
                             'category': 0,