ZIP Splitter

The ZIP Splitter is a specialized Splitter from Hohpe and Woolf. It decomposes a multi-entry ZIP archive into one exchange per entry. Each entry flows through the route as its own message.

    let route = camel_builder::RouteBuilder::from("timer:zip-marshal?period=3000&repeatCount=2")
        .route_id("zip-marshal-route")
        .set_body("payload for ZIP compression")
        .log("Route 3: Original body", LogLevel::Info)
        .marshal("zip")?
        .log("Route 3: After marshal to ZIP", LogLevel::Info)
        .unmarshal("zip")?
        .log(
            "Route 3: After unmarshal from ZIP (round-trip!)",
            LogLevel::Info,
        )
        .to("log:zip-result?showBody=true")
        .error_handler(ErrorHandlerConfig::log_only())
        .build()?;

- id: zip-marshal-route
  from: timer:zip-marshal?period=3000&repeatCount=2
  error_handler: {}
  steps:
    - set_body: "payload for ZIP compression"
    - log: "Route 3: Original body"
    - marshal: zip
    - log: "Route 3: After marshal to ZIP"
    - unmarshal: zip
    - log: "Route 3: After unmarshal from ZIP (round-trip!)"
    - to: log:zip-result?showBody=true

The included route runs a timer that fires twice. The .marshal("zip") step compresses the body into a single-entry archive. The .unmarshal("zip") step decompresses it back. The route logs the byte sizes at each step. A reader can watch the body shrink during compression and grow during decompression.

The actual split happens through the zip_splitter expression and the StreamingSplitterService. The expression reads the ZIP central directory and emits one exchange per entry. Each exchange carries the entry body plus headers: CAMEL_ZIP_ENTRY_NAME, CAMEL_ZIP_ENTRY_PATH, CAMEL_ZIP_ENTRY_SIZE, and CAMEL_ZIP_ENTRY_INDEX. The ZipSplitConfig struct caps the entry count, the per-entry size, and the total decompressed size.

The ZIP Splitter is format-specific. It knows how to parse the ZIP archive structure. The Streaming Splitter is the generic alternative. It splits any byte stream through a codec that the content type selects. Use the ZIP Splitter when the input is a ZIP archive and you need per-entry headers. Use the Streaming Splitter for NDJSON, log lines, or raw byte chunks.

Per ADR-0001, the splitter compiles into a Service<Exchange> step in the Tower middleware pipeline. The per-entry sub-pipeline compiles into child steps on the same route channel. The processor contract is documented in camel-processor/CONTEXT.md.

The example source is at examples/zip-splitter.