nullable-request-body-custom-commands

name: nullable-request-body-custom-commands description: How to author custom commands for the nullable-request-body CLI using the co-generated SDK.

Custom Commands for nullable-request-body

Overview

The nullable-request-body CLI supports user-authored custom commands that are compiled into the binary alongside the auto-generated API commands. Custom commands get a fully-wired SDK client that inherits the CLI's auth, retries, TLS, base URL, and global headers — zero configuration required.

Architecture

cli/nullable-request-body/custom.rs    ← Your command handlers (protected by .fernignore)
cli/nullable-request-body/sdk.rs       ← Generated bridge: client() + block_on()
cli/nullable-request-body/main.rs      ← Generated entrypoint (calls custom::register)
nullable-request-body-sdk/             ← Co-generated typed SDK crate
nullable-request-body-types/           ← Co-generated typed model crate

Adding a Custom Command

1. Edit cli/nullable-request-body/custom.rs

This file is protected by .fernignore — fern generate will never overwrite it. Register commands in the register() function:

use nullable_request_body_sdk::api::*;

pub fn register(app: CliApp) -> CliApp {
    let app = app.command(
        clap::Command::new("test-method-name")
            .about("Post Nullable Request Body")
            .arg(clap::Arg::new("path_param").required(true))
        ,
        |matches, ctx| {
            let path_param = matches.get_one::<String>("path_param").unwrap();
            let client = super::sdk::client(ctx);
            let result = super::sdk::block_on(
                client.test_group.test_method_name(path_param),
            )?;
            println!("{}", serde_json::to_string_pretty(&result).unwrap());
            Ok(())
        },
    );
    app
}

Then build and test:

cargo build
nullable-request-body test-method-name <path_param>

2. Available SDK Clients

The super::sdk::client(ctx) call returns a nullable_request_body_sdk::api::Client with the following sub-clients:

3. Key Patterns

Get the SDK client (execution-sharing, fully authenticated):

let client = super::sdk::client(ctx);

Run an async SDK call from a sync handler:

let result = super::sdk::block_on(
    client.some_resource.some_method(args),
)?;

Use typed models for request/response serialization:

use nullable_request_body_sdk::api::*;

Regeneration Safety

After running fern generate, your custom.rs is preserved. All generated code (SDK, types, glue, main.rs) is updated to match the latest API spec. If the SDK surface changes (renamed methods, new sub-clients), update your custom.rs to match.

Build & Test

# Build the CLI (includes custom commands)
cargo build

# Run your custom command
nullable-request-body <your-command> [args]

# Run with verbose output for debugging
RUST_LOG=debug nullable-request-body <your-command> [args]