Merge pull request #6 from streamnsight/master

fix for redistimeseries breaking changes + pattern search

GrafanaDatastoreServer.py

@@ -3,7 +3,7 @@
 import argparse
 import redis
 import flask
-import calendar
+from datetime import timedelta, datetime
 import dateutil.parser
 from gevent.pywsgi import WSGIServer
 from flask import Flask, jsonify
@@ -12,6 +12,8 @@
 app = Flask(__name__)
 CORS(app)
 
+EPOCH = datetime(1970, 1, 1, 0, 0, 0)
+
 REDIS_POOL = None
 SCAN_TYPE_SCRIPT = """local cursor, pat, typ, cnt = ARGV[1], ARGV[2], ARGV[3], ARGV[4] or 100
 local rep = {}
@@ -41,7 +43,7 @@ def search():
     cursor = 0
     while True:
         cursor, keys = redis_client.eval(SCAN_TYPE_SCRIPT, 0, cursor, "*", "TSDB-TYPE", 100)
-        result.extend(keys)
+        result.extend([k.decode("ascii") for k in keys])
         if cursor == 0:
             break
 
@@ -51,7 +53,7 @@ def process_targets(targets, redis_client):
     result = []
     for target in targets:
         if '*' in target:
-            result.extend(redis_client.keys(target))
+            result.extend([k.decode('ascii') for k in redis_client.keys(target)])
         else:
             result.append(target)
     return result
@@ -61,19 +63,22 @@ def query():
     request = flask.request.get_json()
     response = []
 
-    stime = calendar.timegm(dateutil.parser.parse(request['range']['from']).timetuple())
-    etime = calendar.timegm(dateutil.parser.parse(request['range']['to']).timetuple())
+    # !!! dates 'from' and 'to' are expected to be in UTC, which is what Grafana provides here.
+    # If not in UTC, use pytz to set to UTC timezone and subtract the utcoffset().
+    # Time delta calculations should always be done in UTC to avoid pitfalls of daylight offset changes.
+    stime = (dateutil.parser.parse(request['range']['from']) - EPOCH) / timedelta(milliseconds=1)
+    etime = (dateutil.parser.parse(request['range']['to']) - EPOCH) / timedelta(milliseconds=1)
 
     redis_client = redis.Redis(connection_pool=REDIS_POOL)
     targets = process_targets([t['target'] for t in request['targets']], redis_client)
 
     for target in targets:
         args = ['ts.range', target, int(stime), int(etime)]
-        if 'intervalMs' in request and request['intervalMs'] > 0 and request['intervalMs']/1000 > 1:
-            args += ['avg', int(round(request['intervalMs']/1000))]
+        if 'intervalMs' in request and request['intervalMs'] > 0:
+            args += ['avg', int(request['intervalMs'])]
         print(args)
         redis_resp = redis_client.execute_command(*args)
-        datapoints = [(float(x2.decode("ascii")), x1*1000) for x1, x2 in redis_resp]
+        datapoints = [(float(x2.decode("ascii")), x1) for x1, x2 in redis_resp]
         response.append(dict(target=target, datapoints=datapoints))
     return jsonify(response)