Add simple paging to artifacts page

There must be a library for this.. but I don't know of it.

2 files changed, 38 insertions, 2 deletions

diff --git a/morphcacheserver/artifact_database.py b/morphcacheserver/artifact_database.py
index 9bc35a9..b9550a1 100644
--- a/morphcacheserver/artifact_database.py
+++ b/morphcacheserver/artifact_database.py
@@ -141,6 +141,24 @@ class ArtifactDatabase(object):
                 'hash_sha1': hash_sha1
             }
 
+    def count_artifacts(self):
+        '''Return the number of known artifacts.
+
+        This may include artifacts where the actual files aren't stored in the
+        cache, as we allow submitting just the hash in order to check
+        reproducibility.
+
+        '''
+        n_artifacts_sql = '''
+        SELECT COUNT(cache_name) FROM artifact_files
+        '''
+
+        cursor = self.db.cursor()
+        logging.debug('Running: %s', n_artifacts_sql)
+        cursor.execute(n_artifacts_sql)
+
+        return cursor.fetchone()[0]
+
     def view_artifact_statistics(self, start=0, page_size=50):
         '''Return information on number of builds for each artifact.
 
diff --git a/morphcacheserver/frontend.py b/morphcacheserver/frontend.py
index 0376aa0..bc21f70 100644
--- a/morphcacheserver/frontend.py
+++ b/morphcacheserver/frontend.py
@@ -13,7 +13,9 @@
 # with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 
-from bottle import Bottle, template
+from bottle import Bottle, request, template
+
+import math
 
 
 def make_table(data, heading_ids, heading_titles):
@@ -47,14 +49,30 @@ def web_frontend(db):
     def artifacts():
         '''View artifacts in the cache.'''
 
+        # This causes a 500 error if the parameter is not an integer.
+        page = int(request.query.get('page', 1))
+        page_size = 50
+
         content = '<p>Artifacts:</p>'
 
-        artifacts = db.view_artifact_statistics()
+        artifacts = db.view_artifact_statistics(
+            start=(page-1)*page_size, page_size=page_size)
         content += make_table(
             artifacts,
             ['cache_name', 'n_builds', 'n_different_builds'],
             ['Artifact', 'Total builds', 'Mismatching builds'])
 
+        n_artifacts = db.count_artifacts()
+        n_pages = int(math.ceil(n_artifacts / float(page_size)))
+
+        content += '<p>Page %i of %i</p>' % (page, n_pages)
+        if page > 1:
+            content += '<a href="?page=%i">prev</a>' % (page-1)
+            if page < n_pages:
+                content += ' -- '
+        if page < n_pages:
+            content += '<a href="?page=%i">next</a>' % (page+1)
+
         return template('morphcacheserver/templates/base', base=content)
 
     @app.get('/')