beremiz

Conform to pep8 and pylint :

2019-04-07, Edouard Tisserant
8fb5c6eddc72
Conform to pep8 and pylint :

pep8 version: 2.3.1
./ConfigTreeNode.py:130:49: E231 missing whitespace after ','
./editors/Viewer.py:643:24: E128 continuation line under-indented for visual indent
./editors/Viewer.py:670:12: E221 multiple spaces before operator
./editors/Viewer.py:671:13: E221 multiple spaces before operator
./editors/Viewer.py:2138:52: E203 whitespace before ':'
./editors/Viewer.py:2139:66: W291 trailing whitespace
./controls/VariablePanel.py:154:25: E231 missing whitespace after ','
./controls/LocationCellEditor.py:88:1: W293 blank line contains whitespace
./controls/LocationCellEditor.py:191:25: E221 multiple spaces before operator
./controls/LocationCellEditor.py:200:17: E128 continuation line under-indented for visual indent

pylint 1.8.3,
************* Module controls.LocationCellEditor
controls/LocationCellEditor.py:200: [C0330(bad-continuation), ] Wrong continued indentation (add 9 spaces).
_("Selected location is identical to previous one"))
^ |
************* Module controls.VariablePanel
controls/VariablePanel.py:154: [E1601(print-statement), VariableTable.SetValue] print statement used
************* Module editors.Viewer
editors/Viewer.py:643: [C0330(bad-continuation), ] Wrong continued indentation (add 1 space).
self.GetAddMenuCallBack(self.AddNewComment))
^|
editors/Viewer.py:598: [W0612(unused-variable), Viewer.AddDivergenceMenuItems] Unused variable 'add_branch'
editors/Viewer.py:1655: [E0602(undefined-variable), Viewer.PopupConnectionMenu] Undefined variable 'variable_type'
editors/Viewer.py:1649: [W0612(unused-variable), Viewer.PopupConnectionMenu] Unused variable 'connection_type'
************* Module connectors.PYRO.PSK_Adapter
Beremiz and Beremiz_service connectors
======================================
To connect a PLC, Beremiz provides 2 types of connectors :
* a Pyro connector
* a WAMP connector
To configure the connection, you have to set the *URI_location* in your project Config tab according to this documentation.
The Pyro connector
----------------------------
Pyro is an advanced and powerful Distributed Object Technology system written entirely in Python.
Beremiz_service spawns a Pyro server, serving a PLCObject (see runtime/PLCObject.py). Therefore, Beremiz acts as a Pyro client.
TODO:: link to PLCObject API documentation
URI_location :
* LOCAL:// is a facility that starts the PLC service locally and connect Beremiz to it via Pyro.
This is intended for use in development stage.
* PYRO://<ip:port> normal connection to a remote PLC. PLC default port is 3000.
* PYROS://<ip:port> SSL connection to a remote PLC, see below.
more information about Pyro can be found on http://pythonhosted.org//Pyro/1-intro.html
===========================
Setup a Pyro SSL connection
===========================
Pyro v3 has a limited TLS/SSL support based on m2crypto. Pyro v4 had dropped it.
In order to have a full and reliable SSL, we recommand to use a TLS/SSL wrapper as nginx, stub or stunnel.
--------------------
TLS-PSK with stunnel
--------------------
In this example, we setup a simple TLS-PSK connection according to rfc4279.
This ciphersuite avoid the need for public key operations and certificate management.
It is perfect for a performance-constrained environments with limited CPU power as a PLC.
Needed :
* stunnel >= 5.09
verify openssl support for PSK cipher::
openssl ciphers -v 'PSK'
----------------------
Client setup (Beremiz)
----------------------
You need to choose an identity for your client, here *client1*.
generate a valid and strong key::
$ echo client1:$(openssl rand -base64 48) > pskclient1.txt
write a stunnel client configuration file *stunnel-client.conf*::
output = stunnel-client.log
client = yes
[beremiz]
accept = 3002
connect = [PLC]:3001
PSKidentity = client1
PSKsecrets = pskclient1.txt
start stunnel client side::
stunnel stunnel-client.conf
You could now connect beremiz with classic URI_location = PYRO://127.0.0.1:3002
--------------------
Server setup (PLC)
--------------------
import the client key in a keyfile psk.txt, concatening all client key.
write a stunnel server configuration file *stunnel-server.conf*::
output = stunnel-server.log
[beremiz]
accept = 3001
connect = 127.0.0.1:3000
PSKsecrets = psk.txt
start stunnel server side::
stunnel stunnel-server.conf
more documentation on stunnel http://www.stunnel.org/docs.html
The WAMP connector
------------------
WAMP is an open standard WebSocket subprotocol that provides two application messaging
patterns in one unified protocol: Remote Procedure Calls + Publish & Subscribe.
Beremiz WAMP connector implementation uses Autobahn and crossbar.
URI_location :
* WAMP://127.0.0.1:8888#Automation#2534667845
more information about WAMP can be found on http://wamp.ws/