daemon-cli

A streaming daemon-client framework for Rust with automatic lifecycle management and stdin/stdout streaming.

Features

• Auto-spawning daemons with mtime-based version synchronization
• Streaming stdin/stdout interface
• Ctrl+C cancellation support
• Custom exit codes (0-255) for command results
• Generic payload support for passing custom data from client to daemon
• Cross-platform (Linux, macOS, Windows)

Installation

[dependencies]
daemon-cli = "0.9.0"

Usage

Implement a handler:

use daemon_cli::prelude::*;use tokio::io::{AsyncWrite,AsyncWriteExt};#[derive(Clone)]structMyHandler;#[async_trait]implCommandHandlerforMyHandler{asyncfnhandle(&self,command:&str,ctx:CommandContext,mutoutput:implAsyncWrite + Unpin + Send,cancel:CancellationToken,) -> Result<i32>{// Access terminal info via ctx.terminal_info
output.write_all(format!("Received: {}\n", command).as_bytes()).await?;Ok(0)// Return exit code (0 = success)}}

Run daemon:

let root_path = "/path/to/project";let(server, _handle) = DaemonServer::new(root_path,MyHandler,StartupReason::default());
server.run().await?;

Run client:

let root_path = "/path/to/project";letmut client = DaemonClient::connect(root_path).await?;let exit_code = client.execute_command(command).await?;
std::process::exit(exit_code);

Custom Payload

Pass custom data from client to daemon using PayloadCollector:

use daemon_cli::prelude::*;#[derive(Serialize,Deserialize,Clone,Default)]structMyPayload{cwd:String,user:Option<String>,}#[async_trait]implPayloadCollectorforMyPayload{asyncfncollect() -> Self{Self{cwd: std::env::current_dir().map(|p| p.display().to_string()).unwrap_or_default(),user: std::env::var("USER").ok(),}}}// Handler receives payload in ctx.payload#[async_trait]implCommandHandler<MyPayload>forMyHandler{asyncfnhandle(&self,command:&str,ctx:CommandContext<MyPayload>,mutoutput:implAsyncWrite + Unpin + Send,cancel:CancellationToken,) -> Result<i32>{println!("CWD: {}", ctx.payload.cwd);Ok(0)}}// Client with payloadlet client = DaemonClient::<MyPayload>::connect(root_path).await?;

Exit Codes

Handlers return custom exit codes (0-255):

• Ok(0) - Success
• Ok(1-255) - Application-specific error codes
• Err(e) - Unrecoverable error (becomes exit code 1)

Example

See examples/cli.rs for a complete working example:

cargo run --example cli -- daemon
echo"status"| cargo run --example cli

Platform

Cross-platform: Linux, macOS, Windows. Uses Unix domain sockets on Unix and named pipes on Windows.