nushell/crates/nu-plugin/README.md

nu-plugin

Updating Cap'n Proto schema

When modifying a protocol's struct that is used in plugins (such as Signature), you need to update the capnproto schema file and recompile it into the Rust source code. The steps are as follows:

1. Change src/serializers/capnp/schema/plugin.capnp as necessary
2. Install capnp tool (it's a C++ binary, commonly available in package managers)
3. Install Rust support for capnp called capnpc-rust:
   1. git clone https://github.com/capnproto/capnproto-rust somewhere
   2. cd capnproto-rust/capnpc
   3. cargo install --path=.
4. Then, call capnp compile -orust plugin.capnp (change path as necessary)
5. The result should be plugin_capnp.rs file: Use it to replace the old src/plugin_capnp.rs.
6. It needs to be autoformatted (cargo fmt --all)
7. Modify the serialize/deserialize functions. Check the following PRs for details:
   • https://github.com/nushell/nushell/pull/4980
   • https://github.com/nushell/nushell/pull/4920

Benchmark

Here is a simple benchmark for different protocol for encoding/decoding nushell table, with different rows and columns. You can simply run cargo bench to run benchmark.

The relative html report is in target/criterion/report/index.html.