Config

The Config engine reads a program's settings as one typed value: a declaration of every setting and its default, then files and the environment in the order you write them. Secrets print as ***, required settings must be given, and settings marked live change while the program runs, for every process of the store at once.

const config = await store.config('chat', [
	{ port: 8080, model: { api_key: secret(String), max_tokens: live(1024) } },
	file('chat.toml', { optional: true }),
	env('CHAT', { vars: { port: 'PORT' } }),
])

config.value.model.max_tokens // read on every request
await config.update({ model: { max_tokens: 2048 } }) // every process sees it
console.table(config.explain()) // each setting, its value and where it came from

config = await store.config("chat", [
    Settings,
    file("chat.toml", optional=True),
    env("CHAT", vars={"port": "PORT"}),
])

config.value.model.max_tokens
await config.update({"model": {"max_tokens": 2048}})
for line in config.explain():
    print(line)

config, err := tinystore.OpenConfig(ctx, store, "chat", defaults,
	tinystore.File("chat.toml", tinystore.Optional()),
	tinystore.Env("CHAT", tinystore.Var("port", "PORT")))

config.Get().Model.MaxTokens
err = config.Update(ctx, func(s *Settings) { s.Model.MaxTokens = 2048 })
for _, line := range config.Explain() {
	fmt.Println(line)
}

let config = store
    .config("chat", Settings::default())
    .file(File::optional("chat.toml"))
    .env(Env::prefix("CHAT").var("port", "PORT"))
    .open()?;

let max_tokens = *config.get().model.max_tokens;
config.update(|s| *s.model.max_tokens = 2048)?;
println!("{}", config.explain());

What it guarantees

The layers are read in the order written, and for each setting the last layer that gives it wins.
A config opens with every layer read, or fails with one error that lists every problem, naming the file or the variable.
Only a live setting changes while the program runs; a change is kept over every layer until reset, and every process sharing the store sees it.
A secret prints as *** everywhere and is never kept in the store.
A key or a variable that names no setting is said, with its nearest name, never silently ignored.

In these guides

Page	Covers
Layers and files	objects, TOML, YAML and JSON files, the environment
Secrets and required settings	`secret`, `required`, `_FILE` variables
Live settings	`live`, `update`, `reset`, `ifVersion`
Watching	`watch` in this process and others
Explain and validate	where a value came from, the program's own checks

New to Config? Settings in the Handbook declares a chat's settings and turns its replies off live.

Reference

Bun and Node · Python · Go · Rust

#What it guarantees

#In these guides

#Reference

What it guarantees

In these guides

Reference