Find, now with pagination! Use limit and skip to get the results you want.

3 files changed, 47 insertions, 21 deletions

diff --git a/README.md b/README.md
index 4348660..8ef8971 100644
--- a/README.md
+++ b/README.md
@@ -97,3 +97,7 @@ We might also filter the data:
 Believe it or not, but we can also get a single observation by looking up its key:
 
     curl -s -u user1:pw1 http://localhost:80/sc/v0/get/1633633714355 | json_pp -json_opt utf8,pretty
+
+We can also limit the number of results and skip N results forward with the parameters limit and skip:
+
+    curl -s -u user1:pw1 http://localhost:80/sc/v0/get?limit=5&skip=2 | json_pp -json_opt utf8,pretty
diff --git a/src/db.py b/src/db.py
index f9d0da1..8ab98e7 100755
--- a/src/db.py
+++ b/src/db.py
@@ -76,24 +76,35 @@ class DictDB():
     def slice(self, key_from=None, key_to=None):
         pass
 
-    def search(self, **kwargs):
+    def search(self, limit=25, skip=0, **kwargs):
         """
-        Execute a Mango query, ideally we should have an index matching the,
+        Execute a Mango query, ideally we should have an index matching
         the query otherwise things will be slow.
         """
 
         data = list()
         selector = dict()
 
+        try:
+            limit = int(limit)
+            skip = int(skip)
+        except ValueError:
+            limit = 25
+            skip = 0
+
         if kwargs:
-            selector = {"selector": {}}
+            selector = {
+                "limit": limit,
+                "skip": skip,
+                "selector": {}
+            }
 
             for key in kwargs:
                 if kwargs[key].isnumeric():
                     kwargs[key] = int(kwargs[key])
                 selector['selector'][key] = {'$eq': kwargs[key]}
 
-        for doc in self.couchdb.find(selector):
+        for doc in self.couchdb.find(selector, wrapper=None, limit=5):
             data.append(doc)
 
         return data
diff --git a/src/wsgi.py b/src/wsgi.py
index 62db3c9..b547ffa 100755
--- a/src/wsgi.py
+++ b/src/wsgi.py
@@ -33,9 +33,11 @@ class CollectorResource():
     def user_auth(self, auth_header, authfun):
         if not auth_header:
             return None, None   # Fail.
+
         BAlit, b64 = auth_header.split()
         if BAlit != "Basic":
             return None, None   # Fail
+
         userbytes, pwbytes = b64decode(b64).split(b':')
         try:
             user = userbytes.decode('utf-8')
@@ -50,14 +52,19 @@ class EPGet(CollectorResource):
         out = list()
         selectors = dict()
 
+        limit = 25
+        skip = 0
+
         resp.status = falcon.HTTP_200
         resp.content_type = falcon.MEDIA_JSON
         orgs = self.user_auth(req.auth, self._users.read_perms)
 
         if not orgs:
             resp.status = falcon.HTTP_401
-            resp.text = json.dumps(
-                {'status': 'error', 'message': 'Invalid username or password\n'})
+            resp.text = json.dumps({
+                'status': 'error',
+                'message': 'Invalid username or password\n'
+            })
             return
 
         if key:
@@ -66,6 +73,10 @@ class EPGet(CollectorResource):
             return
 
         for param in req.params:
+            if param == 'limit':
+                limit = req.params['limit']
+            elif param == 'skip':
+                skip = req.params['skip']
             for i in index.indexes:
                 for j in i['index']['fields']:
                     if j == param:
@@ -73,7 +84,7 @@ class EPGet(CollectorResource):
 
         for org in orgs:
             selectors['domain'] = org
-            data = self._db.search(**selectors)
+            data = self._db.search(**selectors, limit=limit, skip=skip)
             if data:
                 out += data
 
@@ -103,6 +114,7 @@ class EPAdd(CollectorResource):
         # NOTE: Reading the whole body in one go instead of streaming
         # it nicely.
         rawin = req.bounded_stream.read()
+
         try:
             decodedin = rawin.decode('UTF-8')
         except Exception:
@@ -134,25 +146,24 @@ class EPAdd(CollectorResource):
 def main(port=8000, wsgi_helper=False):
     db = DictDB(database, hostname, username, password)
     users = authn.UserDB('wsgi_demo_users.yaml')
-    resources_map = [
-        ('/sc/v0/add', EPAdd(db, users)),
-        ('/sc/v0/get', EPGet(db, users)),
-        ('/sc/v0/get/{key}', EPGet(db, users))
-    ]
-    app = falcon.App(cors_enable=True)
 
-    for url, res in resources_map:
-        app.add_route(url, res)
+    app = falcon.App(cors_enable=True)
+    app.add_route('/sc/v0/add', EPAdd(db, users))
+    app.add_route('/sc/v0/get', EPGet(db, users))
+    app.add_route('/sc/v0/get/{key}', EPGet(db, users))
 
-    if not wsgi_helper:
-        print('Serving on port 8000...')
-        httpd = make_server('', port, app)
-        httpd.serve_forever()
+    if wsgi_helper:
+        return app
 
-    return app
+    print('Serving on port 8000...')
+    httpd = make_server('', port, app)
+    httpd.serve_forever()
 
 
 if __name__ == '__main__':
-    sys.exit(main())
+    try:
+        sys.exit(main())
+    except KeyboardInterrupt:
+        print('\nBye!')
 else:
     app = main(port=8000, wsgi_helper=True)