feature: adds server for host machine

update_server.py

@@ -0,0 +1,103 @@
+#!/usr/bin/env python
+import json
+import logging
+import os
+import subprocess
+import time
+
+RCSTACK_PATH_NAME = "RCSTACK_PATH"
+RCSTACK_PATH = os.environ.get(RCSTACK_PATH_NAME)
+RCSTACK_LOG = os.environ.get("RCSTACK_LOG", "./rcstack_status.log")
+
+try:
+    # Py3
+    from http.server import BaseHTTPRequestHandler, HTTPServer
+except ImportError:
+    # Py2
+    from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
+
+
+log = logging.getLogger("mini-server")
+
+
+class RcstackUpdater(BaseHTTPRequestHandler):
+    def __init__(self, request, client_address, server):
+        super().__init__(request, client_address, server)
+
+    def _send_json_ok(self):
+        body = json.dumps({"status": "ok"}).encode("utf-8")
+        self.send_response(200)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(body)))
+        self.end_headers()
+        self.wfile.write(body)
+
+    def do_GET(self):
+        if self.path == "/health":
+            return self._send_json_ok()
+        elif self.path == "/update-rcstack":
+            ok, err_msg = self.spawn_rcstack_status()
+            if not ok:
+                self._send_http_error(err_msg.encode("utf-8"), status_code=500)
+                return
+
+        self._send_http_error(b"not found", status_code=404)
+
+    def spawn_rcstack_status(self):
+        if not RCSTACK_PATH:
+            return False, f"{RCSTACK_PATH_NAME} env variable not set"
+
+        if not os.path.exists(RCSTACK_PATH) or not os.path.isfile(RCSTACK_PATH):
+            return False, f"{RCSTACK_PATH} does not exist"
+
+        rcstack = os.path.expanduser(RCSTACK_PATH)
+
+        # Append mode; don't use PIPE unless you read it.
+        out = open(RCSTACK_LOG, "ab")
+
+        stamp = time.strftime("%Y-%m-%d %H:%M:%S").encode("utf-8")
+        out.write(b"[" + stamp + b"] spawn: " + rcstack.encode("utf-8") + b" status\n")
+        out.flush()
+
+        # Detach from the request handler process group/session.
+        # start_new_session=True is Py3; preexec_fn=os.setsid works in Py2/3 on Unix.
+        try:
+            rcstack_dir = os.path.dirname(rcstack)
+
+            subprocess.Popen(
+                [rcstack, "status"],
+                cwd=rcstack_dir,
+                stdout=out,
+                stderr=out,
+                close_fds=True,
+                preexec_fn=os.setsid,  # Unix only
+            )
+        finally:
+            out.close()
+
+        return True, None
+
+    def _send_http_error(self, msg, status_code):
+        self.send_response(status_code)
+        self.send_header("Content-Type", "text/plain")
+        self.end_headers()
+        self.wfile.write(msg)
+
+    def log_message(self, fmt, *args):
+        log.info("%s - %s", self.address_string(), fmt % args)
+
+
+def main():
+    logging.basicConfig(
+        level=logging.INFO,
+        format="%(asctime)s %(levelname)s %(name)s: %(message)s",
+    )
+    host = "127.0.0.1"  # allow only run within the system, no external connections allowed
+    port = 10025
+    httpd = HTTPServer((host, port), RcstackUpdater)
+    log.info("listening on http://%s:%d", host, port)
+    httpd.serve_forever()
+
+
+if __name__ == "__main__":
+    main()