Update examples to use dynamic host IP instead of hardcoded localhost

examples/doc-examples/example_encryption_insecure.py

@@ -1,6 +1,5 @@
 import secrets
 
-import multiaddr
 import trio
 
 from libp2p import (
@@ -9,9 +8,10 @@ from libp2p import (
 from libp2p.crypto.secp256k1 import (
     create_new_key_pair,
 )
-from libp2p.security.insecure.transport import (
-    PLAINTEXT_PROTOCOL_ID,
-    InsecureTransport,
+from libp2p.security.insecure.transport import PLAINTEXT_PROTOCOL_ID, Transport
+from libp2p.utils.address_validation import (
+    get_available_interfaces,
+    get_optimal_binding_address,
 )
 
 
@@ -21,7 +21,7 @@ async def main():
     key_pair = create_new_key_pair(secret)
 
     # Create an insecure transport (not recommended for production)
-    insecure_transport = InsecureTransport(
+    insecure_transport = Transport(
         # local_key_pair: The key pair used for libp2p identity
         local_key_pair=key_pair,
         # secure_bytes_provider: Optional function to generate secure random bytes
@@ -38,17 +38,19 @@ async def main():
     # Create a host with the key pair and insecure transport
     host = new_host(key_pair=key_pair, sec_opt=security_options)
 
-    # Configure the listening address
+    # Configure the listening address using the new paradigm
     port = 8000
-    listen_addr = multiaddr.Multiaddr(f"/ip4/127.0.0.1/tcp/{port}")
+    listen_addrs = get_available_interfaces(port)
+    optimal_addr = get_optimal_binding_address(port)
 
     # Start the host
-    async with host.run(listen_addrs=[listen_addr]):
+    async with host.run(listen_addrs=listen_addrs):
         print(
             "libp2p has started with insecure transport "
             "(not recommended for production)"
         )
         print("libp2p is listening on:", host.get_addrs())
+        print(f"Optimal address: {optimal_addr}")
         # Keep the host running
         await trio.sleep_forever()
 

examples/doc-examples/example_encryption_noise.py

@@ -1,6 +1,5 @@
 import secrets
 
-import multiaddr
 import trio
 
 from libp2p import (
@@ -13,6 +12,10 @@ from libp2p.security.noise.transport import (
     PROTOCOL_ID as NOISE_PROTOCOL_ID,
     Transport as NoiseTransport,
 )
+from libp2p.utils.address_validation import (
+    get_available_interfaces,
+    get_optimal_binding_address,
+)
 
 
 async def main():
@@ -39,14 +42,16 @@ async def main():
     # Create a host with the key pair and Noise security
     host = new_host(key_pair=key_pair, sec_opt=security_options)
 
-    # Configure the listening address
+    # Configure the listening address using the new paradigm
     port = 8000
-    listen_addr = multiaddr.Multiaddr(f"/ip4/127.0.0.1/tcp/{port}")
+    listen_addrs = get_available_interfaces(port)
+    optimal_addr = get_optimal_binding_address(port)
 
     # Start the host
-    async with host.run(listen_addrs=[listen_addr]):
+    async with host.run(listen_addrs=listen_addrs):
         print("libp2p has started with Noise encryption")
         print("libp2p is listening on:", host.get_addrs())
+        print(f"Optimal address: {optimal_addr}")
         # Keep the host running
         await trio.sleep_forever()
 

examples/doc-examples/example_encryption_secio.py

@@ -1,6 +1,5 @@
 import secrets
 
-import multiaddr
 import trio
 
 from libp2p import (
@@ -13,6 +12,10 @@ from libp2p.security.secio.transport import (
     ID as SECIO_PROTOCOL_ID,
     Transport as SecioTransport,
 )
+from libp2p.utils.address_validation import (
+    get_available_interfaces,
+    get_optimal_binding_address,
+)
 
 
 async def main():
@@ -32,14 +35,16 @@ async def main():
     # Create a host with the key pair and SECIO security
     host = new_host(key_pair=key_pair, sec_opt=security_options)
 
-    # Configure the listening address
+    # Configure the listening address using the new paradigm
     port = 8000
-    listen_addr = multiaddr.Multiaddr(f"/ip4/127.0.0.1/tcp/{port}")
+    listen_addrs = get_available_interfaces(port)
+    optimal_addr = get_optimal_binding_address(port)
 
     # Start the host
-    async with host.run(listen_addrs=[listen_addr]):
+    async with host.run(listen_addrs=listen_addrs):
         print("libp2p has started with SECIO encryption")
         print("libp2p is listening on:", host.get_addrs())
+        print(f"Optimal address: {optimal_addr}")
         # Keep the host running
         await trio.sleep_forever()
 

examples/doc-examples/example_net_stream.py

@@ -234,7 +234,7 @@ async def run_enhanced_demo(
 
 def main() -> None:
     example_maddr = (
-        "/ip4/127.0.0.1/tcp/8000/p2p/QmQn4SwGkDZKkUEpBRBvTmheQycxAHJUNmVEnjA2v1qe8Q"
+        "/ip4/[HOST_IP]/tcp/8000/p2p/QmQn4SwGkDZKkUEpBRBvTmheQycxAHJUNmVEnjA2v1qe8Q"
     )
 
     parser = argparse.ArgumentParser(

examples/doc-examples/example_peer_discovery.py

@@ -1,6 +1,5 @@
 import secrets
 
-import multiaddr
 import trio
 
 from libp2p import (
@@ -16,6 +15,10 @@ from libp2p.security.noise.transport import (
     PROTOCOL_ID as NOISE_PROTOCOL_ID,
     Transport as NoiseTransport,
 )
+from libp2p.utils.address_validation import (
+    get_available_interfaces,
+    get_optimal_binding_address,
+)
 
 
 async def main():
@@ -42,14 +45,16 @@ async def main():
     # Create a host with the key pair, Noise security, and mplex multiplexer
     host = new_host(key_pair=key_pair, sec_opt=security_options)
 
-    # Configure the listening address
+    # Configure the listening address using the new paradigm
     port = 8000
-    listen_addr = multiaddr.Multiaddr(f"/ip4/127.0.0.1/tcp/{port}")
+    listen_addrs = get_available_interfaces(port)
+    optimal_addr = get_optimal_binding_address(port)
 
     # Start the host
-    async with host.run(listen_addrs=[listen_addr]):
+    async with host.run(listen_addrs=listen_addrs):
         print("libp2p has started")
         print("libp2p is listening on:", host.get_addrs())
+        print(f"Optimal address: {optimal_addr}")
 
         # Connect to bootstrap peers manually
         bootstrap_list = [

examples/doc-examples/example_quic_transport.py

@@ -1,6 +1,5 @@
 import secrets
 
-import multiaddr
 import trio
 
 from libp2p import (
@@ -9,6 +8,10 @@ from libp2p import (
 from libp2p.crypto.secp256k1 import (
     create_new_key_pair,
 )
+from libp2p.utils.address_validation import (
+    get_available_interfaces,
+    get_optimal_binding_address,
+)
 
 
 async def main():
@@ -19,14 +22,24 @@ async def main():
     # Create a host with the key pair
     host = new_host(key_pair=key_pair, enable_quic=True)
 
-    # Configure the listening address
+    # Configure the listening address using the new paradigm
     port = 8000
-    listen_addr = multiaddr.Multiaddr(f"/ip4/127.0.0.1/udp/{port}/quic-v1")
+    listen_addrs = get_available_interfaces(port, protocol="udp")
+    # Convert TCP addresses to QUIC-v1 addresses
+    quic_addrs = []
+    for addr in listen_addrs:
+        addr_str = str(addr).replace("/tcp/", "/udp/") + "/quic-v1"
+        from multiaddr import Multiaddr
+        quic_addrs.append(Multiaddr(addr_str))
+
+    optimal_addr = get_optimal_binding_address(port, protocol="udp")
+    optimal_quic_str = str(optimal_addr).replace("/tcp/", "/udp/") + "/quic-v1"
 
     # Start the host
-    async with host.run(listen_addrs=[listen_addr]):
+    async with host.run(listen_addrs=quic_addrs):
         print("libp2p has started with QUIC transport")
         print("libp2p is listening on:", host.get_addrs())
+        print(f"Optimal address: {optimal_quic_str}")
         # Keep the host running
         await trio.sleep_forever()