Add documentation for the simple client-server example using the new SDK

Author: dieriver

examples/distributed/teleport/run.sh

@@ -2,7 +2,8 @@
 
 # Check if SimulaQron is already running
 if [ ! -f ~/.simulaqron_pids/simulaqron_network_default.pid ]; then
-    simulaqron start --nodes=Alice,Bob --network-config-file ./networkConfig.json
+    # If not, start simulaqron backend for both nodes
+    simulaqron start --nodes=Alice,Bob --network-config-file simulaqron_network.json
 fi
 
 python3 teleport-bob.py &

examples/new-sdk/classical-client-server/README.md

@@ -0,0 +1,76 @@
+# Classical Client-Server example
+
+Very simple example to demonstrate how to write client-server applications which exchange
+classical messages.
+
+
+# How to run
+
+There are two ways to run this example:
+
+
+## On a single machine
+
+The simplest way to run this example is on a single machine. To do this, you can use the
+provided bash script:
+
+```shell
+./run.sh
+```
+
+Alternatively, you can manually start the client and teh server in two different terminals.
+First, start the server on one terminal
+
+```shell
+python example_server_alice.py
+```
+
+which start the server and keeps listening for new incoming connections. Then start the client:
+
+```shell
+python example_client_bob.py
+```
+
+which will connect to the server and send a message that will be sent back by the server.
+
+
+## On different machines
+
+To run this example on different machines, it is necessary that both machines can reach each
+other via a network (or the internet). Additionally, you need to know the IP addresses of both
+machines.
+
+Assuming that the server (alice) will run on a machine with IP `192.168.0.1` and the client (bob)
+will run on the machine with IP `192.168.0.2`, modify the `simulaqron_network.json` file *on both*
+the server and the client to look like this:
+
+```json
+[
+    {
+        "name": "default",
+        "nodes":  [
+            {
+                "Alice": {
+                    "app_socket": ["192.168.0.1", 8821],
+                    "qnodeos_socket": ["192.168.0.1", 8822],
+                    "vnode_socket": ["192.168.0.1", 8823]
+                }
+            },
+            {
+                "Bob": {
+                    "app_socket": ["192.168.0.2", 9831],
+                    "qnodeos_socket": ["192.168.0.2", 9832],
+                    "vnode_socket": ["192.168.0.2", 9833]
+                }
+            }
+        ],
+        "topology": null
+    }
+]
+```
+
+Note that the `localhost` entries from Alice were changed to `192.168.0.1`. Similarly, the
+`localhost` entries from Bob were changed to `192.168.0.2`.
+
+After these modifications, start the server and client in their respective terminals as described
+before.

…lassical-client-server/example_client.py …ical-client-server/example_client_bob.pyexamples/new-sdk/classical-client-server/example_client.py renamed to examples/new-sdk/classical-client-server/example_client_bob.py examples/new-sdk/classical-client-server/example_client.py renamed to examples/new-sdk/classical-client-server/example_client_bob.py

@@ -9,12 +9,13 @@
 async def client_code(reader: StreamReader, writer: StreamWriter):
     data = "Hello World!".encode("utf-8")
     writer.write(data)
-    print(f"Sent message '{data.decode("utf-8")}'")
+    print(f"Client sent message '{data.decode("utf-8")}'")
     result = await reader.read(255)
-    print(f"Received message: '{result.decode("utf-8")}'")
+    print(f"Client received message: '{result.decode("utf-8")}'")
     writer.close()
 
 if __name__ == "__main__":
+    # This is "Bob" - the client
     # Load the file network configuration file
     network_config_file = Path("simulaqron_network.json")
     network_config.read_from_file(network_config_file)

…lassical-client-server/example_server.py …al-client-server/example_server_alice.pyexamples/new-sdk/classical-client-server/example_server.py renamed to examples/new-sdk/classical-client-server/example_server_alice.py examples/new-sdk/classical-client-server/example_server.py renamed to examples/new-sdk/classical-client-server/example_server_alice.py

@@ -8,11 +8,13 @@
 
 async def connection_handler(reader: StreamReader, writer: StreamWriter):
     result = await reader.read(255)
-    print(f"Received message: '{result.decode("utf-8")}'")
+    print(f"Server received message: '{result.decode("utf-8")}'")
     writer.write(result)
+    print(f"Server send message: '{result.decode("utf-8")}'")
     writer.close()
 
 if __name__ == "__main__":
+    # This is "Alice" - the server
     # Load the file network configuration file
     network_config_file = Path("simulaqron_network.json")
     network_config.read_from_file(network_config_file)

examples/new-sdk/classical-client-server/run.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+# Running SimulaQron backend is not needed for this example.
+## Check if SimulaQron is already running
+#if [ ! -f ~/.simulaqron_pids/simulaqron_network_default.pid ]; then
+#    # If not, start simulaqron backend for both nodes
+#    simulaqron start --nodes=Alice,Bob --network-config-file simulaqron_network.json
+#fi
+
+# Run the server
+python3 example_server_alice.py &
+# Wait 1 second for the server to fully start
+sleep 1
+# Run the client
+python3 example_client_bob.py &