acme-versioned-custom-commands
DevelopmentHow to author custom commands for the acme-versioned CLI using the co-generated SDK.
How to use this skill
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Custom Commands for acme-versioned
Overview
The acme-versioned 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/acme-versioned/custom.rs ← Your command handlers (protected by .fernignore)
cli/acme-versioned/sdk.rs ← Generated bridge: client() + block_on()
cli/acme-versioned/main.rs ← Generated entrypoint (calls custom::register)
acme-versioned-sdk/ ← Co-generated typed SDK crate
acme-versioned-types/ ← Co-generated typed model crate
Adding a Custom Command
1. Edit cli/acme-versioned/custom.rs
This file is protected by .fernignore — fern generate will never
overwrite it. Register commands in the register() function:
use acme_versioned_sdk::api::*;
pub fn register(app: CliApp) -> CliApp {
let app = app.command(
clap::Command::new("my-command")
.about("Description of your command")
.arg(clap::Arg::new("id").required(true)),
|matches, ctx| {
let id = matches.get_one::<String>("id").unwrap();
let client = super::sdk::client(ctx);
let result = super::sdk::block_on(
client.v1.get(id),
)?;
println!("{}", serde_json::to_string_pretty(&result).unwrap());
Ok(())
},
);
app
}
2. Available SDK Clients
The super::sdk::client(ctx) call returns a acme_versioned_sdk::api::Client
with the following sub-clients:
| Field | Type | Description |
|---|---|---|
client.v1 | acme_versioned_sdk::api::V1Client | v1 operations |
client.v2 | acme_versioned_sdk::api::V2Client | v2 operations |
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 acme_versioned_sdk::api::*;
4. Authentication
Custom commands automatically inherit the CLI's authentication. The following auth schemes are configured:
- bearerAuth (bearer): env
ACME_VERSIONED_TOKEN
No manual auth wiring is needed in custom command handlers.
Regeneration Safety
| File | Regenerated? | Notes |
|---|---|---|
cli/acme-versioned/custom.rs | No | Protected by .fernignore |
cli/acme-versioned/sdk.rs | Yes | Bridges AppContext → SDK client |
cli/acme-versioned/main.rs | Yes | Calls custom::register(app) |
acme-versioned-sdk/ | Yes | Co-generated typed SDK crate |
acme-versioned-types/ | Yes | Co-generated typed models |
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
acme-versioned <your-command> [args]
# Run with verbose output for debugging
RUST_LOG=debug acme-versioned <your-command> [args]