1 files changed, 93 insertions, 0 deletions
diff --git a/klippy/extras/bulk_sensor.py b/klippy/extras/bulk_sensor.py
index 28aed48a..8f166ec8 100644
--- a/klippy/extras/bulk_sensor.py
+++ b/klippy/extras/bulk_sensor.py
@@ -5,6 +5,99 @@
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import threading
 
+API_UPDATE_INTERVAL = 0.500
+
+# Helper to periodically transmit data to a set of API clients
+class APIDumpHelper:
+    def __init__(self, printer, data_cb, startstop_cb=None,
+                 update_interval=API_UPDATE_INTERVAL):
+        self.printer = printer
+        self.data_cb = data_cb
+        if startstop_cb is None:
+            startstop_cb = (lambda is_start: None)
+        self.startstop_cb = startstop_cb
+        self.is_started = False
+        self.update_interval = update_interval
+        self.update_timer = None
+        self.clients = {}
+    def _stop(self):
+        self.clients.clear()
+        reactor = self.printer.get_reactor()
+        reactor.unregister_timer(self.update_timer)
+        self.update_timer = None
+        if not self.is_started:
+            return reactor.NEVER
+        try:
+            self.startstop_cb(False)
+        except self.printer.command_error as e:
+            logging.exception("API Dump Helper stop callback error")
+            self.clients.clear()
+        self.is_started = False
+        if self.clients:
+            # New client started while in process of stopping
+            self._start()
+        return reactor.NEVER
+    def _start(self):
+        if self.is_started:
+            return
+        self.is_started = True
+        try:
+            self.startstop_cb(True)
+        except self.printer.command_error as e:
+            logging.exception("API Dump Helper start callback error")
+            self.is_started = False
+            self.clients.clear()
+            raise
+        reactor = self.printer.get_reactor()
+        systime = reactor.monotonic()
+        waketime = systime + self.update_interval
+        self.update_timer = reactor.register_timer(self._update, waketime)
+    def add_client(self, web_request):
+        cconn = web_request.get_client_connection()
+        template = web_request.get_dict('response_template', {})
+        self.clients[cconn] = template
+        self._start()
+    def add_internal_client(self):
+        cconn = InternalDumpClient()
+        self.clients[cconn] = {}
+        self._start()
+        return cconn
+    def _update(self, eventtime):
+        try:
+            msg = self.data_cb(eventtime)
+        except self.printer.command_error as e:
+            logging.exception("API Dump Helper data callback error")
+            return self._stop()
+        if not msg:
+            return eventtime + self.update_interval
+        for cconn, template in list(self.clients.items()):
+            if cconn.is_closed():
+                del self.clients[cconn]
+                if not self.clients:
+                    return self._stop()
+                continue
+            tmp = dict(template)
+            tmp['params'] = msg
+            cconn.send(tmp)
+        return eventtime + self.update_interval
+
+# An "internal webhooks" wrapper for using APIDumpHelper internally
+class InternalDumpClient:
+    def __init__(self):
+        self.msgs = []
+        self.is_done = False
+    def get_messages(self):
+        return self.msgs
+    def finalize(self):
+        self.is_done = True
+    def is_closed(self):
+        return self.is_done
+    def send(self, msg):
+        self.msgs.append(msg)
+        if len(self.msgs) >= 10000:
+            # Avoid filling up memory with too many samples
+            self.finalize()
+
 # Helper class to store incoming messages in a queue
 class BulkDataQueue:
     def __init__(self, mcu, msg_name, oid):