camel-component-file

File component for rust-camel

Overview

The File component provides file system integration for rust-camel. It can read files from directories (consumer) and write files to directories (producer), supporting various file handling strategies.

Features

• Consumer: Poll directories for new files
• Producer: Write files with various strategies
• File filtering: Include/exclude patterns (regex)
• Post-processing: Delete, move, or no-op after processing
• Recursive directory scanning
• Atomic writes: Temp file prefix support
• Streaming: Zero-copy file reading via ReaderStream (lazy evaluation)
• Security: Path traversal protection

Installation

Add to your Cargo.toml:

[dependencies]
camel-component-file = "0.2"

URI Format

file:directoryPath[?options]

Consumer Options

Producer Options

Usage

Consumer: Read Files

use camel_builder::RouteBuilder;
use camel_component_file::FileComponent;

let route = RouteBuilder::from("file:/data/input?noop=true")
    .log("Processing file", camel_processor::LogLevel::Info)
    .to("mock:processed")
    .build()?;

Consumer: Delete After Processing

let route = RouteBuilder::from("file:/data/inbox?delete=true")
    .process(|ex| async move {
        // Process file content
        Ok(ex)
    })
    .build()?;

Consumer: Move After Processing

let route = RouteBuilder::from("file:/data/inbox?move=.done")
    .to("direct:process")
    .build()?;

Consumer: Filter by Pattern

// Only process .csv files
let route = RouteBuilder::from("file:/data/input?include=.*\\.csv")
    .to("mock:csv-files")
    .build()?;

Producer: Write Files

let route = RouteBuilder::from("timer:tick?period=1000")
    .set_body("Generated content")
    .set_header("CamelFileName", Value::String("output.txt".into()))
    .to("file:/data/output")
    .build()?;

Producer: Append Mode

let route = RouteBuilder::from("direct:logs")
    .set_header("CamelFileName", Value::String("app.log".into()))
    .to("file:/var/log?fileExist=Append")
    .build()?;

Producer: Atomic Writes

let route = RouteBuilder::from("direct:data")
    .set_header("CamelFileName", Value::String("data.json".into()))
    .to("file:/data/output?tempPrefix=.tmp")
    .build()?;

Exchange Headers

Consumer Headers

Producer Headers

Example: File Pipeline

use camel_builder::RouteBuilder;
use camel_component_file::FileComponent;
use camel_core::CamelContext;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut ctx = CamelContext::new();
    ctx.register_component("file", Box::new(FileComponent::new()));

    // Process files from input, write to output
    let route = RouteBuilder::from("file:/data/input?move=.processed&delay=1000")
        .process(|ex| async move {
            // Transform content
            let body = ex.input.body.as_text().unwrap_or("").to_uppercase();
            let mut ex = ex;
            ex.input.body = Body::Text(body);
            Ok(ex)
        })
        .set_header_fn("CamelFileName", |ex| {
            let original = ex.input.header("CamelFileNameOnly")
                .and_then(|v| v.as_str())
                .unwrap_or("output");
            Value::String(format!("processed_{}", original))
        })
        .to("file:/data/output")
        .build()?;

    ctx.add_route(route).await?;
    ctx.start().await?;

    tokio::signal::ctrl_c().await?;
    ctx.stop().await?;

    Ok(())
}

Streaming & Memory Management

The File component uses lazy evaluation—files are not loaded into memory until the body is accessed. A default 10MB materialization limit prevents out-of-memory conditions when processing large files. This design allows handling files of any size (tested with 150MB+). Users can explicitly materialize with custom limits if needed.

Security

The File component includes protection against path traversal attacks. Attempts to write files outside the configured directory (e.g., using ../ in the filename) will be rejected with an error.

• Memory limits: Default 10MB limit prevents unbounded memory consumption

Documentation

• API Documentation
• Repository

License

Apache-2.0

Contributing

Contributions are welcome! Please see the main repository for details.