diff --git a/swh/web/ui/controller.py b/swh/web/ui/controller.py
index 49ab52a46..8bd157747 100755
--- a/swh/web/ui/controller.py
+++ b/swh/web/ui/controller.py
@@ -1,92 +1,79 @@
 # Copyright (C) 2015  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 
 import logging
 
 from flask import redirect, render_template, url_for, flash, request
 
 
 from swh.web.ui.main import app
-from swh.web.ui import query
 from swh.web.ui import service
 
 
 @app.route('/')
 def main():
     """Main application view.
     At the moment, redirect to the content search view.
     """
     return redirect(url_for('info'))
 
 
 @app.route('/info')
 def info():
     """A simple api to define what the server is all about.
 
     """
     logging.info('Dev SWH UI')
     return 'Dev SWH UI'
 
 
-def lookup_hash(query_hash):
-    """Lookup a hash in the query.
-
-    """
-    hashes = query.group_by_checksums(query.parse(query_hash))
-    if hashes != {}:
-        present = service.search(hashes)
-        return 'Found!' if present else 'Not Found'
-    return """This is not a hash.
-Hint: hexadecimal string with length either 20 (sha1) or 32 (sha256)."""
-
-
 @app.route('/search')
 def search():
     """Search for hashes in swh-storage.
 
     """
     q = request.args.get('q', '')
 
     if q:
         flash("Search hash '%s' posted!" % q)
-        message = lookup_hash(q)
+        message = service.lookup_hash(q)
     else:
         message = ''
 
     return render_template('search.html',
                            q=q,
                            message=message)
 
 def run(conf):
     """Run the api's server.
 
     Args:
         conf is a dictionary of keywords:
         - 'db_url' the db url's access (through psycopg2 format)
         - 'content_storage_dir' revisions/directories/contents storage on disk
         - 'host'   to override the default 127.0.0.1 to open or not the server
         to the world
         - 'port'   to override the default of 5000 (from the underlying layer:
         flask)
         - 'debug'  activate the verbose logs
 
     Returns:
         Never
 
     Raises:
         ?
 
     """
     print("""SWH Web UI run
 host: %s
 port: %s
 debug: %s""" % (conf['host'], conf.get('port', None), conf['debug']))
 
     app.config.update({'conf': conf})
 
     app.run(host=conf['host'],
             port=conf.get('port', None),
             debug=conf['debug'])
diff --git a/swh/web/ui/service.py b/swh/web/ui/service.py
index a9e41f180..1ca765335 100755
--- a/swh/web/ui/service.py
+++ b/swh/web/ui/service.py
@@ -1,23 +1,28 @@
 # Copyright (C) 2015  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 
 from swh.web.ui import main
+from swh.web.ui import query
 
 
-def search(hashes):
-    """Search a content with given hashes.
+def lookup_hash(q):
+    """Given a string query q of hashes, lookup its hash to the backend.
 
     Args:
-         hashes, dictionary of hash indexed by key, sha1, sha256, etc...
+         query, string of ':' delimited hashes (sha1, sha256, etc...)
 
     Returns:
-         None if no content is found.
-         An enriched content if the content is found.
+         a string message (found, not found or a potential error explanation)
 
     Raises:
          OSError (no route to host), etc... Network issues in general
     """
-    return main.storage().content_present(hashes)
+    hashes = query.group_by_checksums(query.parse(q))
+    if hashes != {}:
+        present = main.storage().content_present(hashes)
+        return 'Found!' if present else 'Not Found'
+    return """This is not a hash.
+Hint: hexadecimal string with length either 20 (sha1) or 32 (sha256)."""