Use EDDN gateway's idea of time-of-day rather than NTP's

Reverts ea0c3d3

EDMarketConnector.py

@@ -11,7 +11,7 @@ from os import chdir, mkdir, environ
 from os.path import dirname, expanduser, isdir, join
 import re
 import requests
-from time import time, localtime, strftime, strptime
+from time import gmtime, time, localtime, strftime, strptime
 from calendar import timegm
 import webbrowser
 
@@ -35,6 +35,7 @@ import Tkinter as tk
 import ttk
 import tkFileDialog
 import tkFont
+import tkMessageBox
 from ttkHyperlinkLabel import HyperlinkLabel
 
 if __debug__:
@@ -57,7 +58,6 @@ import coriolis
 import eddb
 import edshipyard
 import loadout
-from ntp import NTPCheck
 import stats
 import prefs
 import plug
@@ -71,6 +71,11 @@ EDDB = eddb.EDDB()
 SERVER_RETRY = 5	# retry pause for Companion servers [s]
 EDSM_POLL = 0.1
 
+# Limits on local clock drift from EDDN gateway
+DRIFT_THRESHOLD = 3 * 60
+TZ_THRESHOLD = 30 * 60
+CLOCK_THRESHOLD = 11 * 60 * 60 + TZ_THRESHOLD
+
 
 class AppWindow:
 
@@ -310,7 +315,15 @@ class AppWindow:
             except:
                 if __debug__: print_exc()
 
-        if not NTPCheck(self.w):	# Check system time
+        # Check system time
+        drift = abs(time() - self.eddn.time())
+        if drift > DRIFT_THRESHOLD:
+            tkMessageBox.showerror(applongname,
+                                   _('This app requires accurate timestamps.') + '\n' +	# Error message shown if system time is wrong
+                                   (TZ_THRESHOLD < drift < CLOCK_THRESHOLD and
+                                    _("Check your system's Time Zone setting.") or		# Error message shown if system time is wrong
+                                    _("Check your system's Date and Time settings.")),	# Error message shown if system time is wrong
+                                   parent = self.w)
             self.w.destroy()
             return
 

L10n/en.template

@@ -52,10 +52,10 @@
 /* Menu item. [EDMarketConnector.py] */
 "Check for Updates..." = "Check for Updates...";
 
-/* Error message shown if system time is wrong. [ntp.py] */
+/* Error message shown if system time is wrong. [EDMarketConnector.py] */
 "Check your system's Date and Time settings." = "Check your system's Date and Time settings.";
 
-/* Error message shown if system time is wrong. [ntp.py] */
+/* Error message shown if system time is wrong. [EDMarketConnector.py] */
 "Check your system's Time Zone setting." = "Check your system's Time Zone setting.";
 
 /* Federation rank. [stats.py] */
@@ -481,7 +481,7 @@
 /* Appearance setting. [prefs.py] */
 "Theme" = "Theme";
 
-/* Error message shown if system time is wrong. [ntp.py] */
+/* Error message shown if system time is wrong. [EDMarketConnector.py] */
 "This app requires accurate timestamps." = "This app requires accurate timestamps.";
 
 /* Help text in settings. [prefs.py] */

README.md

@@ -178,17 +178,17 @@ Download and extract the source code of the [latest release](https://github.com/
 
 Mac:
 
-* Requires the Python “keyring”, “ntplib”, “requests” and “watchdog” modules, plus an up-to-date “py2app” module if you also want to package the app - install these with `easy_install -U keyring ntplib requests watchdog py2app` .
+* Requires the Python “keyring”, “requests” and “watchdog” modules, plus an up-to-date “py2app” module if you also want to package the app - install these with `easy_install -U keyring requests watchdog py2app` .
 * Run with `./EDMarketConnector.py` .
 
 Windows:
 
-* Requires Python2.7 and the Python “keyring”, “ntplib”, “requests” and “watchdog” modules, plus “py2exe” 0.6 if you also want to package the app.
+* Requires Python2.7 and the Python “keyring”, “requests” and “watchdog” modules, plus “py2exe” 0.6 if you also want to package the app.
 * Run with `EDMarketConnector.py` .
 
 Linux:
 
-* Requires the Python “imaging-tk”, “iniparse”, “keyring”, “ntplib” and “requests” modules. On Debian-based systems install these with `sudo apt-get install python-imaging-tk python-iniparse python-ntplib python-keyring python-requests` .
+* Requires the Python “imaging-tk”, “iniparse”, “keyring” and “requests” modules. On Debian-based systems install these with `sudo apt-get install python-imaging-tk python-iniparse python-keyring python-requests` .
 * Run with `./EDMarketConnector.py` .
 
 Command-line

eddn.py

@@ -10,6 +10,7 @@ import re
 import requests
 from sys import platform
 import time
+from calendar import timegm
 import uuid
 
 if platform != 'win32':
@@ -29,8 +30,10 @@ replayfile = None	# For delayed messages
 
 class EDDN:
 
-    ### UPLOAD = 'http://localhost:8081/upload/'	# testing
-    UPLOAD = 'http://eddn-gateway.elite-markets.net:8080/upload/'
+    ### SERVER = 'http://localhost:8081/'	# testing
+    SERVER = 'http://eddn-gateway.elite-markets.net:8080/'
+    UPLOAD = '%s/upload/' % SERVER
+    HEALTH = '%s/health_check/' % SERVER
     REPLAYPERIOD = 400	# Roughly two messages per second, accounting for send delays [ms]
     REPLAYFLUSH = 20	# Update log on disk roughly every 10 seconds
 
@@ -76,6 +79,17 @@ class EDDN:
             replayfile.close()
         replayfile = None
 
+    def time(self):
+        # Returns the EDDN gateway's idea of time-of-day.
+        # Assumes that the gateway returns a strictly compliant Date - https://tools.ietf.org/html/rfc7231#section-7.1.1.1
+        try:
+            r = self.session.get(self.HEALTH, timeout=timeout)
+            return timegm(time.strptime(r.headers['Date'], "%a, %d %b %Y %H:%M:%S GMT"))
+        except:
+            # On any error assume that we're good
+            if __debug__: print_exc()
+            return time.time()
+
     def send(self, cmdr, msg):
         if config.getint('anonymous'):
             uploaderID = config.get('uploaderID')

ntp.py

@@ -1,28 +0,0 @@
-from ntplib import NTPClient
-from tkMessageBox import showerror
-
-from config import applongname
-
-if __debug__:
-    from traceback import print_exc
-
-def NTPCheck(parent):
-
-    DRIFT_THRESHOLD = 3 * 60
-    TZ_THRESHOLD = 30 * 60
-    CLOCK_THRESHOLD = 12 * 60 * 60 + DRIFT_THRESHOLD
-
-    try:
-        response = NTPClient().request('pool.ntp.org')
-        if abs(response.offset) > DRIFT_THRESHOLD:
-            showerror(applongname,
-                      _('This app requires accurate timestamps.') + '\n' +	# Error message shown if system time is wrong
-                      (TZ_THRESHOLD < abs(response.offset) < CLOCK_THRESHOLD and
-                       _("Check your system's Time Zone setting.") or		# Error message shown if system time is wrong
-                       _("Check your system's Date and Time settings.")),	# Error message shown if system time is wrong
-                      parent = parent)
-            return False
-    except:
-        if __debug__: print_exc()
-
-    return True