Adding mDNS logic to manually resolve .local hostnames. This is added…

… for a few reasons, but mostly to make the system more robust.

.github/workflows/pylint.yml

@@ -23,6 +23,7 @@ jobs:
         pip install octoflatbuffers
         pip install pillow
         pip install certifi
+        pip install dnspython
         pip install rsa
         pip install sentry-sdk
         pip install octoprint

.vscode/settings.json

@@ -17,6 +17,7 @@
         "deps",
         "DGRAM",
         "didnt",
+        "dnspython",
         "filamentchange",
         "firewalled",
         "firstlayerdone",
@@ -37,6 +38,7 @@
         "levelname",
         "localauth",
         "localip",
+        "mdns",
         "mjpeg",
         "mjpegstreamer",
         "Mjpg",
@@ -74,6 +76,8 @@
         "Pursa",
         "Pylint",
         "pythoncompat",
+        "rdataclass",
+        "rdclass",
         "referer",
         "repeattimer",
         "requestsutils",

devnotes.md

@@ -19,7 +19,7 @@
 
 
 ## Install Other Branches:
-    - https://github.com/QuinnDamerell/OctoPrint-OctoEverywhere/archive/pip.zip
+    - https://github.com/QuinnDamerell/OctoPrint-OctoEverywhere/archive/mdns.zip
 
 ## Before checking in:
 - Run in py2 env

octoprint_octoeverywhere/WebStream/octowebstreamwshelper.py

@@ -9,6 +9,7 @@
 from octoprint_octoeverywhere.sentry import Sentry
 
 from ..octohttprequest import OctoHttpRequest
+from ..mdns import MDns
 from ..octostreammsgbuilder import OctoStreamMsgBuilder
 from ..localip import LocalIpHelper
 from ..websocketimpl import Client
@@ -38,6 +39,7 @@ def __init__(self, streamId, logger, webStream, webStreamOpenMsg, openedTime):
         self.OpenedTime = openedTime
         self.Ws = None
         self.FirstWsMessageSentToLocal = False
+        self.ResolvedLocalHostnameUrl = None
 
         # These vars indicate if the actual websocket is opened or closed.
         # This is different from IsClosed, which is tracking if the webstream closed status.
@@ -128,14 +130,41 @@ def AttemptConnection(self):
                 self.Logger.info(self.getLogMsgPrefix()+" failed to connect to relative path and has nothing else to try.")
                 return False
         elif pathType is PathTypes.PathTypes.Absolute:
-            # If the path is absolute, we only have this one path to try.
-            if self.ConnectionAttempt != 0:
-                # Report the issue and return False to indicate we aren't trying to connect.
-                self.Logger.info(self.getLogMsgPrefix()+" failed to connect to absolute path and has nothing else to try.")
-                return False
-
-            # Make an absolute path
-            uri = path
+            # If this is an absolute path, there are two options:
+            #   1) If the path is a local hostname, we will try to manually resolve the hostname and then try that connection directly.
+            #      This is to mitigate mDNS problems, which are described in octohttprequest, in the PathTypes.Absolute handling logic.
+            #      Basically, mDNS is flakey and it's not supported on some OSes, so doing it ourselves fixes some of that.
+            #        - If this is the case, we will try our manually resolved url first, and the OG second.
+            #   2) If the url isn't a local hostname or it fails to resolve manually, we just use the absolute URL directly.
+
+            # Try to see if this is a local hostname, if we don't already have a result.
+            if self.ResolvedLocalHostnameUrl is None:
+                # This returns None if the URL doesn't contain a local hostname or it fails to resolve.
+                self.ResolvedLocalHostnameUrl = MDns.Get().TryToResolveIfLocalHostnameFound(path)
+
+            if self.ResolvedLocalHostnameUrl is None:
+                # If self.ResolvedLocalHostnameUrl is None, there's no local hostname or it failed to resolve.
+                # Thus we will just try the absolute URL and nothing else.
+                if self.ConnectionAttempt != 0:
+                    # Report the issue and return False to indicate we aren't trying to connect.
+                    self.Logger.info(self.getLogMsgPrefix()+" failed to connect to absolute path and has nothing else to try.")
+                    return False
+
+                # Use the raw absolute path.
+                uri = path
+            else:
+                # We have a local hostname url resolved in our string.
+                if self.ConnectionAttempt == 0:
+                    # For the first attempt, try using our manually resolved URL. Since it's already resolved and might be from a cache, it's going to be faster.
+                    uri = self.ResolvedLocalHostnameUrl
+                elif self.ConnectionAttempt == 1:
+                    # For the second attempt, it means the manually resolved URL failed, so we just try the original path with no modification.
+                    self.Logger.info(self.getLogMsgPrefix()+" failed to connect with the locally resoled hostname ("+self.ResolvedLocalHostnameUrl+"), trying the raw URL. " + path)
+                    uri = path
+                else:
+                    # We tired both, neither worked. Give up.
+                    self.Logger.info(self.getLogMsgPrefix()+" failed to connect to manually resolved local hostname and the absolute path.")
+                    return False
         else:
             raise Exception("Web stream ws helper got a open message with an unknown path type "+str(pathType))
 

octoprint_octoeverywhere/__init__.py

@@ -22,6 +22,7 @@
 from .octopingpong import OctoPingPong
 from .slipstream import Slipstream
 from .sentry import Sentry
+from .mdns import MDns
 from .smartpause import SmartPause
 
 
@@ -164,6 +165,9 @@ def on_startup(self, host, port):
         # Init the ping helper
         OctoPingPong.Init(self._logger, self.get_plugin_data_folder(), printerId)
 
+        # Init the mdns helper
+        MDns.Init(self._logger, self.get_plugin_data_folder())
+
         # Create the notification object now that we have the logger.
         self.NotificationHandler = NotificationsHandler(self._logger, self._printer)
         self.NotificationHandler.SetPrinterId(printerId)

octoprint_octoeverywhere/__main__.py

@@ -12,6 +12,7 @@
 from .octopingpong import OctoPingPong
 from .slipstream import Slipstream
 from .sentry import Sentry
+from .mdns import MDns
 from .notificationshandler import NotificationsHandler
 #from .threaddebug import ThreadDebug
 
@@ -36,6 +37,9 @@
 PrinterId = "0QVGBOO92TENVOVN9XW5T3KT6LV1XV8ODFUEQYWQ"
 PrivateKey = "uduuitfqrsstnhhjpsxhmyqwvpxgnajqqbhxferoxunusjaybodfotkupjaecnccdxzwmeajqqmjftnhoonusnjatqcryxfvrzgibouexjflbrmurkhltmsd"
 
+# Defines a place we can write files
+PluginFilePathRoot = "C:\\Users\\quinn"
+
 # A mock of the popup UI interface.
 class UiPopupInvokerStub():
     def __init__(self, logger):
@@ -100,6 +104,10 @@ def GeneratePrinterId():
     # Init Sentry, but it won't report since we are in dev mode.
     Sentry.Init(logger, "dev", True)
 
+    # Init the mdns client
+    MDns.Init(logger, PluginFilePathRoot)
+    #MDns.Get().Test()
+
     # This is a tool to help track stuck or leaked threads.
     #threadDebugger = ThreadDebug()
     #threadDebugger.Start(logger, 30)
@@ -129,7 +137,7 @@ def GeneratePrinterId():
     LocalAuth.Get().SetApiKeyForTesting("SuperSecureApiKey")
 
     # Init the ping pong helper.
-    OctoPingPong.Init(logger, "C:\\Users\\quinn", PrinterId)
+    OctoPingPong.Init(logger, PluginFilePathRoot, PrinterId)
     # If we are using a local dev connection, disable this or it will overwrite.
     if OctoEverywhereWsUri.startswith("ws://"):
         OctoPingPong.Get().DisablePrimaryOverride()