LibP2P Documentation

https://libp2p.io/docs/
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### Start Basic go-libp2p Node

Source: https://libp2p.io/docs/getting-started-go

Create a main.go file to start a libp2p node with default settings, print its listening addresses, and then shut it down. This is the foundational node setup.

```go
package main

import (
    "fmt"
    "github.com/libp2p/go-libp2p"
)

func main() {
    // start a libp2p node with default settings
    node, err := libp2p.New()
    if err != nil {
        panic(err)
    }

    // print the node's listening addresses
    fmt.Println("Listen addresses:", node.Addrs())

    // shut the node down
    if err := node.Close(); err != nil {
        panic(err)
    }
}
```

--------------------------------

### Clone the libp2p-webrtc-guide repository

Source: https://libp2p.io/docs/webrtc-browser-connectivity

Clone the repository to get started with the guide. This is the initial step to access the project files.

```bash
git clone https://github.com/libp2p/libp2p-webrtc-guide
```

--------------------------------

### Install npm dependencies

Source: https://libp2p.io/docs/webrtc-browser-connectivity

Navigate into the cloned repository and install the necessary npm dependencies for the project. This step is crucial before running any part of the guide.

```bash
cd libp2p-webrtc-guide
npm install
```

--------------------------------

### Install go-libp2p Dependencies

Source: https://libp2p.io/docs/webrtc-browser-connectivity

Navigate to the go-relay directory and install the necessary Go dependencies.

```bash
cd go-relay
go get .
```

--------------------------------

### Install libp2p Module

Source: https://libp2p.io/docs/getting-started-javascript

Install the core libp2p module to your project.

```bash
npm install libp2p
```

--------------------------------

### Install Dependencies on Windows (WSL)

Source: https://libp2p.io/docs/local-testing-strategies

Sets up the testing environment within WSL Ubuntu, including installing common utilities and yq. Assumes Docker Desktop integration or direct WSL Docker installation.

```bash
# Install WSL2 with Ubuntu
wsl --install -d Ubuntu

# Inside WSL Ubuntu
sudo apt update
sudo apt install -y bash docker.io git curl patch wget zip unzip

# Install yq
sudo wget https://github.com/mikefarah/yq/releases/download/v4.35.1/yq_linux_amd64 \
  -O /usr/local/bin/yq && sudo chmod +x /usr/local/bin/yq

# Configure Docker (ensure Docker Desktop WSL integration is enabled)
# Or install Docker in WSL directly

# Clone unified-testing
git clone https://github.com/libp2p/unified-testing.git
cd unified-testing
```

--------------------------------

### Start and Stop libp2p Node

Source: https://libp2p.io/docs/getting-started-javascript

Demonstrates the full lifecycle of a libp2p node, including starting it, logging listening addresses, and subsequently stopping it. Ensure you have configured transports, encryption, and stream multiplexers before starting.

```javascript
import { createLibp2p } from 'libp2p'
import { tcp } from '@libp2p/tcp'
import { noise } from '@chainsafe/libp2p-noise'
import { yamux } from '@chainsafe/libp2p-yamux'

const main = async () => {
  const node = await createLibp2p({
    addresses: {
      // add a listen address (localhost) to accept TCP connections on a random port
      listen: ['/ip4/127.0.0.1/tcp/0']
    },
    transports: [tcp()],
    connectionEncrypters: [noise],
    streamMuxers: [yamux()]
  })

  // start libp2p
  await node.start()
  console.log('libp2p has started')

  // print out listening addresses
  console.log('listening on addresses:')
  node.getMultiaddrs().forEach((addr) => {
    console.log(addr.toString())
  })

  // stop libp2p
  await node.stop()
  console.log('libp2p has stopped')
}

main().then().catch(console.error)

```

--------------------------------

### Start a Listening libp2p Node

Source: https://libp2p.io/docs/getting-started-go

Run this command in a terminal to start a libp2p node that listens for incoming connections. No command-line arguments are needed.

```bash
./libp2p-node
lbp2p node address: /ip4/192.0.2.0/tcp/61790/ipfs/QmZKjsGJ6ukXVRXVEcExx9GhiyWoJC97onYpzBwCHPWqpL
```

--------------------------------

### Install TCP Transport Module

Source: https://libp2p.io/docs/getting-started-javascript

Install the @libp2p/tcp module for establishing network connections.

```bash
npm install @libp2p/tcp
```

--------------------------------

### Start Frontend Development Server

Source: https://libp2p.io/docs/webrtc-browser-connectivity

Execute this command to launch the frontend development server for the browser peer.

```bash
npm run start
```

--------------------------------

### Check Go Version

Source: https://libp2p.io/docs/getting-started-go

Verify that your Go installation is version 1.20 or higher. This is a prerequisite for the tutorial.

```bash
$ go version
go version go1.20 darwin/arm64
```

--------------------------------

### Install Noise Connection Encryption Module

Source: https://libp2p.io/docs/getting-started-javascript

Install the @chainsafe/libp2p-noise module for encrypting connections.

```bash
npm install @chainsafe/libp2p-noise
```

--------------------------------

### Install yq from GitHub Releases

Source: https://libp2p.io/docs/local-testing-strategies

Install the `yq` command-line YAML processor by downloading the binary directly from GitHub releases. This ensures you are using the correct version and avoids conflicts with snap packages.

```bash
sudo wget https://github.com/mikefarah/yq/releases/download/v4.35.1/yq_linux_amd64 \
  -O /usr/local/bin/yq && sudo chmod +x /usr/local/bin/yq
```

--------------------------------

### Build and Run go-libp2p Node

Source: https://libp2p.io/docs/getting-started-go

Compile the Go program into an executable and run it. This will start the libp2p node and display its listening addresses.

```bash
$ go build -o libp2p-node

$ ./libp2p-node
Listen addresses: [/ip6/::1/tcp/57666 /ip4/192.0.2.0/tcp/57665 /ip4/198.51.100.0/tcp/57665]
```

--------------------------------

### Configure libp2p Node with Yamux

Source: https://libp2p.io/docs/getting-started-javascript

Initialize a libp2p node with TCP transport, Noise encryption, and Yamux stream multiplexing. This setup is a common starting point for libp2p applications.

```javascript
import { createLibp2p } from 'libp2p'
import { tcp } from '@libp2p/tcp'
import { noise } from '@chainsafe/libp2p-noise'
import { yamux } from '@chainsafe/libp2p-yamux'

const node = await createLibp2p({
  transports: [tcp()],
  connectionEncrypters: [noise()],
  streamMuxers: [yamux()]
})
```

--------------------------------

### Start Node.js Relay

Source: https://libp2p.io/docs/webrtc-browser-connectivity

Run this command in your terminal to start the Node.js relay server.

```bash
npm run start:relay
```

--------------------------------

### Install Dependencies for Ping Pong

Source: https://libp2p.io/docs/getting-started-javascript

Install the necessary packages for multiaddr parsing and the libp2p ping service.

```bash
npm install multiaddr @libp2p/ping
```

--------------------------------

### Test Metadata Example

Source: https://libp2p.io/docs/write-a-perf-test-app

The `perf/lib/run-signle-test.sh` script adds metadata to the results file. This example shows the format of the metadata, including test details, transport, and status.

```yaml
test: rust-v0.56 x rust-v0.56 (quic-v1)
dialer: rust-v0.56
listener: rust-v0.56
transport: quic-v1
secureChannel: null
muxer: null
status: pass
```

--------------------------------

### Install Dependencies on macOS

Source: https://libp2p.io/docs/local-testing-strategies

Installs required tools using Homebrew and verifies the bash version. Includes cloning the unified-testing repository and running a check with the Homebrew bash executable.

```bash
# Using Homebrew
brew install bash docker yq git

# Start Docker Desktop
open -a Docker

# Verify bash version (must be 4.0+)
/opt/homebrew/bin/bash --version

# Clone unified-testing
git clone https://github.com/libp2p/unified-testing.git
cd unified-testing

# Run with Homebrew bash (macOS ships with bash 3.x)
/opt/homebrew/bin/bash perf/run.sh --check-deps
```

--------------------------------

### Install Yamux Stream Multiplexer

Source: https://libp2p.io/docs/getting-started-javascript

Install the Yamux stream multiplexer package using npm. This is a recommended step for efficient connection management in libp2p.

```bash
npm install @chainsafe/libp2p-yamux
```

--------------------------------

### Install Dependencies on Linux (Debian 13)

Source: https://libp2p.io/docs/local-testing-strategies

Installs necessary packages like bash, docker, git, and yq on Debian-based systems. Includes steps for adding the user to the docker group and cloning the unified-testing repository.

```bash
# Ubuntu/Debian
sudo apt update
sudo apt install -y bash docker.io git curl patch wget zip unzip

# Install yq
sudo wget https://github.com/mikefarah/yq/releases/download/v4.35.1/yq_linux_amd64 \
  -O /usr/local/bin/yq && sudo chmod +x /usr/local/bin/yq

# Install Docker Compose v2 (if not included with docker.io)
sudo apt install docker-compose-plugin

# Add user to docker group
sudo usermod -aG docker $USER
newgrp docker

# Clone unified-testing
git clone https://github.com/libp2p/unified-testing.git
cd unified-testing
```

--------------------------------

### Dependency Checker Output

Source: https://libp2p.io/docs/local-testing-strategies

Example output from the `./run.sh --check-deps` command, showing successful verification of versioned tools, required utilities, Docker services, and optional dependencies.

```text
                        ╔╦╦╗  ╔═╗
▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁ ║╠╣╚╦═╬╝╠═╗ ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁
═══════════════════════ ║║║║║║║╔╣║║ ════════════════════════
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ ╚╩╩═╣╔╩═╣╔╝ ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
                            ╚╝  ╚╝

╲ Checking dependencies...
 ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  → Checking versioned tools...
    → bash...              [OK] 5.2
    → docker...            [OK] 29.1.5
    → yq...                [OK] 4.48.1
    → git...               [OK] 2.47.3

  → Checking required utilities...
    → patch...             [OK] 
    → wget...              [OK] 
    → zip...               [OK] 
    → unzip...             [OK] 
    → cut...               [OK] 
    → bc...                [OK] 
    → sha256sum...         [OK] 
    → timeout...           [OK] 
    → flock...             [OK] 
    → tar...               [OK] 
    → gzip...              [OK] 
    → awk...               [OK] 
    → sed...               [OK] 
    → grep...              [OK] 
    → sort...              [OK] 
    → head...              [OK] 
    → tail...              [OK] 
    → wc...                [OK] 
    → tr...                [OK] 
    → paste...             [OK] 
    → cat...               [OK] 
    → mkdir...             [OK] 
    → cp...                [OK] 
    → mv...                [OK] 
    → rm...                [OK] 
    → chmod...             [OK] 
    → find...              [OK] 
    → xargs...             [OK] 
    → basename...          [OK] 
    → dirname...           [OK] 
    → mktemp...            [OK] 
    → date...              [OK] 
    → sleep...             [OK] 
    → uname...             [OK] 
    → hostname...          [OK] 
    → ps...                [OK] 

  → Checking Docker services...
    → docker daemon...     [OK] 
    → docker compose...    [OK] using 'docker compose' 

  → Checking optional dependencies...
    → gnuplot...           [OK] 6.0
    → pandoc...            [OK] 

  ✓ All required dependencies are satisfied
```

--------------------------------

### WebSocket Upgrade Request Example

Source: https://libp2p.io/docs/browser-connectivity

This is an example of an HTTP request used to initiate a WebSocket upgrade. The browser sends this request to the server to establish a WebSocket connection.

```http
GET /chat HTTP/1.1
Host: server.example.com
Upgrade: websocket
Connection: Upgrade

```

--------------------------------

### Example Generated docker-compose.yaml

Source: https://libp2p.io/docs/write-a-transport-test-app

This is an example of a docker-compose.yaml file generated by the transport test suite. It defines the services for a listener and a dialer, including their Docker images, container names, network configurations, and environment variables.

```yaml
name: rust-v0_56_x_rust-v0_56__quic-v1_ 

networks:
  transport-network:
    external: true

services:
  listener:
    image: transport-rust-v0.56
    container_name: rust-v0_56_x_rust-v0_56__quic-v1__listener
    init: true
    networks:
      - transport-network
    environment:
      - IS_DIALER=false
      - REDIS_ADDR=transport-redis:6379
      - TEST_KEY=a5b50d5e
      - TRANSPORT=quic-v1
      - LISTENER_IP=0.0.0.0
      - DEBUG=false

  dialer:
    image: transport-rust-v0.56
    container_name: rust-v0_56_x_rust-v0_56__quic-v1__dialer
    depends_on:
      - listener
    networks:
      - transport-network
    environment:
      - IS_DIALER=true
      - REDIS_ADDR=transport-redis:6379
      - TEST_KEY=a5b50d5e
      - TRANSPORT=quic-v1
      - LISTENER_IP=0.0.0.0
      - DEBUG=false
```

--------------------------------

### Run Libp2p Node Without Arguments

Source: https://libp2p.io/docs/getting-started-javascript

Execute the script without any arguments to start a libp2p node that listens for incoming connections and logs its listening addresses. This is the first step in establishing peer communication.

```bash
> node src/index.js
```

--------------------------------

### Verify Dependencies with run.sh

Source: https://libp2p.io/docs/local-testing-strategies

Executes the dependency checker script for the unified-testing framework. This command verifies that all necessary tools and services are correctly installed and configured.

```bash
cd perf
./run.sh --check-deps
```

--------------------------------

### Configure Bootstrap Peer for Relay

Source: https://libp2p.io/docs/webrtc-browser-connectivity

Configure js-libp2p to automatically connect to the relay peer by adding it to the bootstrap list. Replace the example multiaddr with your actual relay multiaddr.

```javascript
import { bootstrap } from '@libp2p/bootstrap'

const libp2p = await createLibp2p({
  addresses: {
    listen: [
      '/p2p-circuit',
    ],
  },
  transports: [
    webSockets(),
    webTransport(),
    webRTC(),
    circuitRelayTransport(),
  ],
  connectionEncrypters: [noise()],
  streamMuxers: [yamux()],
  connectionGater: {
    // Allow private addresses for local testing
    denyDialMultiaddr: async () => false,
  },
  peerDiscovery: [
      bootstrap({
        // replace with your relay multiaddr
        list: ['/ip4/127.0.0.1/tcp/9001/ws/p2p/12D3KooWQtCgYCZ7JZQoe7Ao6KP5CDMnmEiURqMoarfBgJwbnCPQ'],
      }),
  ],
  services: {
    identify: identify(),
  },
})
```

--------------------------------

### Example Generated Docker Compose Configuration

Source: https://libp2p.io/docs/write-a-perf-test-app

This configuration defines the services, networks, and environment variables for running libp2p performance tests using Docker Compose. It sets up listener and dialer services with specified images and network configurations.

```yaml
name: rust-v0_56_x_rust-v0_56__quic-v1_ 

networks:
  perf-network:
    external: true

services:
  listener:
    image: perf-rust-v0.56
    container_name: rust-v0_56_x_rust-v0_56__quic-v1__listener
    init: true
    networks:
      - perf-network
    environment:
      - IS_DIALER=false
      - REDIS_ADDR=perf-redis:6379
      - TEST_KEY=a5b50d5e
      - TRANSPORT=quic-v1
      - LISTENER_IP=0.0.0.0

  dialer:
    image: perf-rust-v0.56
    container_name: rust-v0_56_x_rust-v0_56__quic-v1__dialer
    depends_on:
      - listener
    networks:
      - perf-network
    environment:
      - IS_DIALER=true
      - REDIS_ADDR=perf-redis:6379
      - TEST_KEY=a5b50d5e
      - TRANSPORT=quic-v1
      - UPLOAD_BYTES=1073741824
      - DOWNLOAD_BYTES=1073741824
      - UPLOAD_ITERATIONS=null
      - DOWNLOAD_ITERATIONS=null
      - LATENCY_ITERATIONS=100
      - DURATION=20

```

--------------------------------

### Create and Initialize npm Project

Source: https://libp2p.io/docs/getting-started-javascript

Create a new directory for your project, initialize it as an npm project, and set the entry point to src/index.js.

```bash
mkdir hello-libp2p
mkdir hello-libp2p/src
cd hello-libp2p
git init .
npm init es6
```

--------------------------------

### Circuit Relay Multiaddress Example

Source: https://libp2p.io/docs/addressing

This multiaddress demonstrates a circuit relay setup, combining multiple peer identities and transport addresses.

```plaintext
/ip4/198.51.100.0/tcp/4242/p2p/QmRelay/p2p-circuit/p2p/QmRelayedPeer
```

--------------------------------

### Initialize Go Module

Source: https://libp2p.io/docs/getting-started-go

Create a new directory and initialize it as a Go module. This sets up the project structure for your libp2p application.

```bash
mkdir -p /tmp/go-libp2p-tutorial
cd /tmp/go-libp2p-tutorial
go mod init github.com/user/go-libp2p-tutorial
```

--------------------------------

### Navigate to Project Directory

Source: https://libp2p.io/docs/webrtc-browser-connectivity

Change to the cloned repository directory to access project files.

```bash
cd libp2p-webrtc-guide
```

--------------------------------

### List Available Implementations

Source: https://libp2p.io/docs/local-testing-strategies

Displays a list of all available implementations that can be used for testing.

```bash
# List available implementations
./run.sh --list-images
```

--------------------------------

### Import go-libp2p Module

Source: https://libp2p.io/docs/getting-started-go

Add the go-libp2p module to your project dependencies. This command fetches the necessary library.

```bash
go get github.com/libp2p/go-libp2p
```

--------------------------------

### Run go-libp2p Relay

Source: https://libp2p.io/docs/webrtc-browser-connectivity

Compile and run the go-libp2p relay from the go-relay folder. The output will display the PeerID and listening multiaddrs.

```bash
go run .
```

--------------------------------

### Import libp2p Packages

Source: https://libp2p.io/docs/getting-started-go

Import necessary packages for libp2p functionality, including the core library and the ping protocol.

```go
import (
    ...

    "github.com/libp2p/go-libp2p"
    "github.com/libp2p/go-libp2p/p2p/protocol/ping"
)
```

--------------------------------

### Performance Test Results Schema Example

Source: https://libp2p.io/docs/write-a-perf-test-app

This is an example of a valid results report that your test application must print to stdout in YAML format. It includes measurements for upload, download, and latency tests, along with raw samples.

```yaml
# Measurements from dialer
upload:
  iterations: 10
  min: 2.04
  q1: 2.05
  median: 2.06
  q3: 2.06
  max: 2.07
  outliers: [2.02]
  samples: [2.02, 2.04, 2.05, 2.05, 2.05, 2.06, 2.06, 2.06, 2.06, 2.07]
  unit: Gbps
download:
  iterations: 10
  min: 2.05
  q1: 2.06
  median: 2.06
  q3: 2.07
  max: 2.08
  outliers: []
  samples: [2.05, 2.05, 2.06, 2.06, 2.06, 2.06, 2.07, 2.07, 2.08, 2.08]
  unit: Gbps
latency:
  iterations: 100
  min: 0.523
  q1: 0.609
  median: 0.634
  q3: 0.671
  max: 0.754
  outliers: [0.473, 0.784, 0.803]
  samples: [0.473, 0.523, 0.551, 0.572, 0.576, 0.577, 0.581, 0.584, 0.589, 0.590, 0.590, 0.592, 0.593, 0.593, 0.594, 0.595, 0.598, 0.598, 0.602, 0.603, 0.604, 0.606, 0.606, 0.607, 0.607, 0.610, 0.610, 0.611, 0.611, 0.612, 0.614, 0.615, 0.616, 0.616, 0.617, 0.618, 0.619, 0.619, 0.621, 0.623, 0.625, 0.625, 0.625, 0.625, 0.626, 0.626, 0.627, 0.627, 0.629, 0.633, 0.635, 0.635, 0.636, 0.637, 0.638, 0.639, 0.640, 0.640, 0.640, 0.641, 0.645, 0.647, 0.647, 0.651, 0.651, 0.651, 0.654, 0.654, 0.660, 0.660, 0.660, 0.661, 0.667, 0.667, 0.670, 0.673, 0.674, 0.676, 0.677, 0.681, 0.684, 0.687, 0.690, 0.691, 0.692, 0.695, 0.695, 0.699, 0.700, 0.704, 0.707, 0.709, 0.714, 0.714, 0.720, 0.733, 0.740, 0.754, 0.784, 0.803]
  unit: ms
```

--------------------------------

### Example IPv4 and UDP Multiaddress

Source: https://libp2p.io/docs/addressing

This multiaddress combines IPv4 addressing with a UDP port.

```plaintext
/ip4/192.0.2.0/udp/1234
```

--------------------------------

### Rebuild and Run Configured Node

Source: https://libp2p.io/docs/getting-started-go

Recompile the application after configuring the listen address and run it. The output will show the explicitly configured listening address.

```bash
$ go build -o libp2p-node

$ ./libp2p-node
Listening addresses: [/ip4/192.0.2.0/tcp/2000]
```

--------------------------------

### Compare Multiple Implementation Versions

Source: https://libp2p.io/docs/local-testing-strategies

Run tests that compare two or more libp2p implementation versions.

```bash
./run.sh --impl-select "rust-v0.55|rust-v0.56"
```

--------------------------------

### Example Peer Identity Multiaddress

Source: https://libp2p.io/docs/addressing

This multiaddress identifies a libp2p node using its Peer ID.

```plaintext
/p2p/QmYyQSo1c1Ym7orWxLYvCrM2EmxFTANf8wXmmE7DWjhx5N
```

--------------------------------

### Example Peer ID String

Source: https://libp2p.io/docs/peers

A Peer ID is represented as a base58-encoded multihash string. This format is standard for libp2p.

```text
QmYyQSo1c1Ym7orWxLYvCrM2EmxFTANf8wXmmE7DWjhx5N
```

--------------------------------

### Example TCP/IP Multiaddress

Source: https://libp2p.io/docs/listen-and-dial

This multiaddress specifies an IPv4 address and a TCP port. It is a common format for network communication.

```plaintext
/ip4/198.51.100.0/tcp/6543
```

--------------------------------

### Import Peer and Multiaddr Packages

Source: https://libp2p.io/docs/getting-started-go

Import packages for handling peer information and multiaddr for network address manipulation.

```go
import (
    ...

    "github.com/libp2p/go-libp2p"
    peerstore "github.com/libp2p/go-libp2p/core/peer"
    "github.com/libp2p/go-libp2p/p2p/protocol/ping"
    multiaddr "github.com/multiformats/go-multiaddr"
)
```

--------------------------------

### Clone and Checkout Implementation Repository

Source: https://libp2p.io/docs/local-testing-strategies

Clones the source repository for an implementation and checks out a specific version to prepare for local modifications.

```bash
cd images/rust/v0.55
git clone https://github.com/libp2p/rust-libp2p .
git checkout v0.55.0
```

--------------------------------

### Test Metadata Example

Source: https://libp2p.io/docs/write-a-hole-punch-test-app

The hole-punch script prepends metadata to the dialer's stdout results. This includes test configuration and status.

```yaml
test: rust-v0.56 x rust-v0.56 (tcp, noise, yamux) [dr: linux, rly: rust-v0.56, lr: linux]
dialer: rust-v0.56
listener: rust-v0.56
dialerRouter: linux
listenerRouter: linux
relay: rust-v0.56
transport: tcp
secureChannel: noise
muxer: yamux
status: pass
```

--------------------------------

### Display Go Module File

Source: https://libp2p.io/docs/getting-started-go

View the contents of the go.mod file after initialization. It shows the module name and the Go version being used.

```bash
$ cat go.mod
module github.com/user/go-libp2p-tutorial

go 1.20
```

--------------------------------

### Example Multiaddress with PeerId

Source: https://libp2p.io/docs/listen-and-dial

This multiaddress includes a PeerId, which uniquely identifies the remote peer. This is used for establishing secure communication channels.

```plaintext
/ip4/192.0.2.0/tcp/4321/p2p/QmcEPrat8ShnCph8WjkREzt5CPXF2RwhYxYBALDcLC1iV6
```

--------------------------------

### Initialize libp2p Node with Custom Ping Handler

Source: https://libp2p.io/docs/getting-started-go

Configure a libp2p node to listen on a random local TCP port and disable the default ping protocol to manually set up a custom ping service.

```go
func main() {
    ...

    // start a libp2p node that listens on a random local TCP port,
    // but without running the built-in ping protocol
    node, err := libp2p.New(
        libp2p.ListenAddrStrings("/ip4/192.0.2.0/tcp/0"),
        libp2p.Ping(false),
    )
    if err != nil {
        panic(err)
    }

    // configure our own ping protocol
    pingService := &ping.PingService{Host: node}
    node.SetStreamHandler(ping.ID, pingService.PingHandler)

    ...
}
```

--------------------------------

### Listener Environment Variable Example

Source: https://libp2p.io/docs/write-a-transport-test-app

When running in listener mode, the test application receives specific environment variables. LISTENER_IP is always set to '0.0.0.0' to bind to all interfaces.

```bash
LISTENER_IP=0.0.0.0
```

--------------------------------

### Configure and Run Libp2p Ping Pong Service

Source: https://libp2p.io/docs/getting-started-javascript

This script sets up a libp2p node with TCP transport, noise encryption, and yamux stream multiplexing. It includes the ping service and can optionally ping a remote peer provided as a command-line argument.

```javascript
import process from 'node:process'
import { createLibp2p } from 'libp2p'
import { tcp } from '@libp2p/tcp'
import { noise } from '@chainsafe/libp2p-noise'
import { yamux } from '@chainsafe/libp2p-yamux'
import { multiaddr } from 'multiaddr'
import { ping } from '@libp2p/ping'

const node = await createLibp2p({
  addresses: {
    // add a listen address (localhost) to accept TCP connections on a random port
    listen: ['/ip4/127.0.0.1/tcp/0']
  },
  transports: [tcp()],
  connectionEncrypters: [noise()],
  streamMuxers: [yamux()],
  services: {
    ping: ping({
      protocolPrefix: 'ipfs', // default
    }),
  },
})

// start libp2p
await node.start()
console.log('libp2p has started')

// print out listening addresses
console.log('listening on addresses:')
node.getMultiaddrs().forEach((addr) => {
  console.log(addr.toString())
})

// ping peer if received multiaddr
if (process.argv.length >= 3) {
  const ma = multiaddr(process.argv[2])
  console.log(`pinging remote peer at ${process.argv[2]}`)
  const latency = await node.services.ping.ping(ma)
  console.log(`pinged ${process.argv[2]} in ${latency}ms`)
} else {
  console.log('no remote peer address given, skipping ping')
}

const stop = async () => {
  // stop libp2p
  await node.stop()
  console.log('libp2p has stopped')
  process.exit(0)
}

process.on('SIGTERM', stop)
process.on('SIGINT', stop)

```
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