Refatoring: Moved .py files into src folder. Unified some file names

src/socket_control.py

@@ -0,0 +1,146 @@
+import globals as g
+from user_interface import ui_print
+import cage_func as cage_controls
+
+from threading import Thread
+import socket
+import numpy as np
+
+# --- Definition of TCP interface ---
+#
+# Clients should by default initialize a TCP connection to port 6677
+# The commands shown must be terminated with a single \n (newline) char
+# Commands may be split across multiple packets.
+# Before useful commands can be sent, declare_api_version must be called.
+#
+# A description of the TCP api (safety limits are always enforced):
+#
+# set_raw_field [X comp.] [Y comp.] [Z comp.]
+#   Returns: 0 or 1 for success
+#   Accepts decimal point formatted floats, with or without scientific notation. The float() cast must understand it.
+#   The field units are Tesla
+#   This causes an additional field of the given strength to be generated, without regard for the pre-existing
+#   geomagnetic/external fields.
+#
+# set_compensated_field [X comp.] [Y comp.] [Z comp.]
+#   Returns: 0 or 1 for success
+#   Accepts decimal point formatted floats, with or without scientific notation. The float() cast must understand it.
+#   The field units are Tesla
+#   This causes a field of exactly the given magnitude to be generated by compensating external factors such as the
+#   geomagnetic field.
+#
+# set_coil_currents [X comp.] [Y comp.] [Z comp.]
+#   Returns: 0 or 1 for success
+#   Accepts decimal point formatted floats, with or without scientific notation. The float() cast must understand it.
+#   The field units are Ampere
+#   This establishes the requested current in the individual coils.
+#
+# get_api_version
+#   Returns: a string uniquely identifying each API version.
+#   This function can be called before declare_api_version.
+#   Please dont put
+#
+# declare_api_version [version]
+#   Returns: 0 or 1 (terminated with newline)
+#   Declare the api version the client application was programmed for. It must be compatible with the current
+#   API version. This prevents unexpected behaviour by forcing programmers to specify which API they are expecting.
+#   This function must be called before sending HW commands.
+
+
+SOCKET_INTERFACE_API_VERSION = "1"
+
+
+class ClientConnectionThread(Thread):
+    def __init__(self, client_socket, address):
+        Thread.__init__(self)
+        self.client_socket = client_socket
+        self.client_address = address
+
+        self.api_compat = False  # Indicates whether the client has a compatible API version
+
+    def run(self):
+        msg = ''
+        while True:
+            raw_msg = self.client_socket.recv(2048).decode()
+            for char in raw_msg:
+                if char == '\n':
+                    msg = msg.rstrip()  # Some systems will try to send \r characters... looking at you windows O_O
+                    try:
+                        response = self.handle_msg(msg)
+                    except Exception as e:
+                        ui_print("An error occurred while processing a client message")
+                        ui_print("Msg: {}".format(msg))
+                        ui_print(e)
+                        response = "err"
+                    self.client_socket.sendall((response + '\n').encode('utf-8'))
+                    msg = ''
+                else:
+                    msg += char
+
+    def handle_msg(self, message):
+        """ Executes command logic and returns string response (for client). """
+        tokens = message.split(" ")
+        if tokens[0] == "get_api_version":
+            return SOCKET_INTERFACE_API_VERSION
+        elif tokens[0] == "declare_api_version":
+            if tokens[1] == SOCKET_INTERFACE_API_VERSION:
+                self.api_compat = True
+                return "1"
+            else:
+                ui_print("Declared socket API version ({}) is incompatible with current version ({})!".format(tokens[1], SOCKET_INTERFACE_API_VERSION))
+                return "0"
+        else:
+            # api_compat indicates we have checked the api version and are ready to accept commands
+            if self.api_compat:
+                if tokens[0] == "set_raw_field":
+                    x = float(tokens[1])
+                    y = float(tokens[2])
+                    z = float(tokens[3])
+                    field_vec = np.array([x, y, z], dtype=np.float32)
+                    # uncompensated
+                    cage_controls.set_field_simple(field_vec)
+                    return "1"
+                elif tokens[0] == "set_compensated_field":
+                    x = float(tokens[1])
+                    y = float(tokens[2])
+                    z = float(tokens[3])
+                    field_vec = np.array([x, y, z], dtype=np.float32)
+                    # compensated
+                    cage_controls.set_field(field_vec)
+                    return "1"
+                elif tokens[0] == "set_coil_currents":
+                    x = float(tokens[1])
+                    y = float(tokens[2])
+                    z = float(tokens[3])
+                    current_vec = np.array([x, y, z], dtype=np.float32)
+                    cage_controls.set_current_vec(current_vec)
+                    return "1"
+                else:
+                    # The message given is unknown. The programmer probably did not intend for this, so display an error
+                    # even if is not inherently problematic.
+                    raise Exception("The command '{}' is unknown".format(tokens[0]))
+            else:
+                raise Exception("The command '{}' may not be called before 'declare_api_version'".format(tokens[0]))
+
+
+class SocketInterfaceThread(Thread):
+    def __init__(self):
+        Thread.__init__(self)
+        self.server_socket = None
+
+        # Can throw exception, which should be passed on to the instantiator of this class
+        self.configure_tcp_port()
+
+    def run(self):
+        while True:
+            (client_socket, address) = self.server_socket.accept()
+            new_thread = ClientConnectionThread(client_socket, address)
+            new_thread.start()
+            ui_print("Accepted connection from {}".format(address))
+
+    def configure_tcp_port(self):
+        # Creates and configures the listening port
+        self.server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.server_socket.bind(('', g.SOCKET_PORT))
+        self.server_socket.listen(5)  # Limit to max. 5 simultaneous connections
+        ui_print("Listening for TCP connections on port {}".format(g.SOCKET_PORT))