Server
Pymodbus offers servers with transport protocols for
Serial (RS-485) typically using a dongle
TCP
TLS
UDP
possibility to add a custom transport protocol
communication in 2 versions:
synchronous server
,asynchronous server
using asyncio.
Remark All servers are implemented with asyncio, and the synchronous servers are just an interface layer allowing synchronous applications to use the server as if it was synchronous.
Server.
import external classes, to make them easier to use:
- class pymodbus.server.ModbusSerialServer(context, framer=Framer.RTU, identity=None, **kwargs)
Bases:
ModbusBaseServer
A modbus threaded serial socket server.
We inherit and overload the socket server so that we can control the client threads as well as have a single server context instance.
- class pymodbus.server.ModbusSimulatorServer(modbus_server: str = 'server', modbus_device: str = 'device', http_host: str = '0.0.0.0', http_port: int = 8080, log_file: str = 'server.log', json_file: str = 'setup.json', custom_actions_module: str | None = None)
Bases:
object
ModbusSimulatorServer.
- Parameters:
modbus_server – Server name in json file (default: “server”)
modbus_device – Device name in json file (default: “client”)
http_host – TCP host for HTTP (default: “localhost”)
http_port – TCP port for HTTP (default: 8080)
json_file – setup file (default: “setup.json”)
custom_actions_module – python module with custom actions (default: none)
if either http_port or http_host is none, HTTP will not be started. This class starts a http server, that serves a couple of endpoints:
“<addr>/” static files
“<addr>/api/log” log handling, HTML with GET, REST-API with post
“<addr>/api/registers” register handling, HTML with GET, REST-API with post
“<addr>/api/calls” call (function code / message) handling, HTML with GET, REST-API with post
“<addr>/api/server” server handling, HTML with GET, REST-API with post
Example:
from pymodbus.server import ModbusSimulatorServer async def run(): simulator = ModbusSimulatorServer( modbus_server="my server", modbus_device="my device", http_host="localhost", http_port=8080) await simulator.run_forever(only_start=True) ... await simulator.stop()
- action_add(params, range_start, range_stop)
Build list of registers matching filter.
- action_clear(_params, _range_start, _range_stop)
Clear register filter.
- action_monitor(params, range_start, range_stop)
Start monitoring calls.
- action_reset(_params, _range_start, _range_stop)
Reset call simulation.
- action_set(params, _range_start, _range_stop)
Set register value.
- action_simulate(params, _range_start, _range_stop)
Simulate responses.
- action_stop(_params, _range_start, _range_stop)
Stop call monitoring.
- build_html_calls(params, html)
Build html calls page.
- build_html_log(_params, html)
Build html log page.
- build_html_registers(params, html)
Build html registers page.
- build_html_server(_params, html)
Build html server page.
- build_json_calls(params, json_dict)
Build html calls page.
- build_json_log(params, json_dict)
Build json log page.
- build_json_registers(params, json_dict)
Build html registers page.
- build_json_server(params, json_dict)
Build html server page.
- async handle_html(request)
Handle html.
- async handle_html_static(request)
Handle static html.
- async handle_json(request)
Handle api registers.
- helper_build_html_submit(params)
Build html register submit.
- async run_forever(only_start=False)
Start modbus and http servers.
- server_request_tracer(request, *_addr)
Trace requests.
All server requests passes this filter before being handled.
- server_response_manipulator(response)
Manipulate responses.
All server responses passes this filter before being sent. The filter returns:
response, either original or modified
skip_encoding, signals whether or not to encode the response
- async start_modbus_server(app)
Start Modbus server as asyncio task.
- async stop()
Stop modbus and http servers.
- async stop_modbus_server(app)
Stop modbus server.
- class pymodbus.server.ModbusTcpServer(context, framer=Framer.SOCKET, identity=None, address=('', 502), ignore_missing_slaves=False, broadcast_enable=False, response_manipulator=None, request_tracer=None)
Bases:
ModbusBaseServer
A modbus threaded tcp socket server.
We inherit and overload the socket server so that we can control the client threads as well as have a single server context instance.
- class pymodbus.server.ModbusTlsServer(context, framer=Framer.TLS, identity=None, address=('', 502), sslctx=None, certfile=None, keyfile=None, password=None, ignore_missing_slaves=False, broadcast_enable=False, response_manipulator=None, request_tracer=None)
Bases:
ModbusTcpServer
A modbus threaded tls socket server.
We inherit and overload the socket server so that we can control the client threads as well as have a single server context instance.
- class pymodbus.server.ModbusUdpServer(context, framer=Framer.SOCKET, identity=None, address=('', 502), ignore_missing_slaves=False, broadcast_enable=False, response_manipulator=None, request_tracer=None)
Bases:
ModbusBaseServer
A modbus threaded udp socket server.
We inherit and overload the socket server so that we can control the client threads as well as have a single server context instance.
- async pymodbus.server.ServerAsyncStop()
Terminate server.
- pymodbus.server.ServerStop()
Terminate server.
- async pymodbus.server.StartAsyncSerialServer(context=None, identity=None, custom_functions=[], **kwargs)
Start and run a serial modbus server.
- Parameters:
context – The ModbusServerContext datastore
identity – An optional identify structure
custom_functions – An optional list of custom function classes supported by server instance.
kwargs – The rest
- async pymodbus.server.StartAsyncTcpServer(context=None, identity=None, address=None, custom_functions=[], **kwargs)
Start and run a tcp modbus server.
- Parameters:
context – The ModbusServerContext datastore
identity – An optional identify structure
address – An optional (interface, port) to bind to.
custom_functions – An optional list of custom function classes supported by server instance.
kwargs – The rest
- async pymodbus.server.StartAsyncTlsServer(context=None, identity=None, address=None, sslctx=None, certfile=None, keyfile=None, password=None, custom_functions=[], **kwargs)
Start and run a tls modbus server.
- Parameters:
context – The ModbusServerContext datastore
identity – An optional identify structure
address – An optional (interface, port) to bind to.
sslctx – The SSLContext to use for TLS (default None and auto create)
certfile – The cert file path for TLS (used if sslctx is None)
keyfile – The key file path for TLS (used if sslctx is None)
password – The password for for decrypting the private key file
custom_functions – An optional list of custom function classes supported by server instance.
kwargs – The rest
- async pymodbus.server.StartAsyncUdpServer(context=None, identity=None, address=None, custom_functions=[], **kwargs)
Start and run a udp modbus server.
- Parameters:
context – The ModbusServerContext datastore
identity – An optional identify structure
address – An optional (interface, port) to bind to.
custom_functions – An optional list of custom function classes supported by server instance.
kwargs –
- pymodbus.server.StartSerialServer(**kwargs)
Start and run a serial modbus server.
- pymodbus.server.StartTcpServer(**kwargs)
Start and run a serial modbus server.
- pymodbus.server.StartTlsServer(**kwargs)
Start and run a serial modbus server.
- pymodbus.server.StartUdpServer(**kwargs)
Start and run a serial modbus server.
- pymodbus.server.get_simulator_commandline(extras=None, cmdline=None)
Get command line arguments.