Providers

Providers are typed resources stored on engines and factories.

Use them to attach external clients or custom resources without global state.

Provider Keys

Create keys with generics:

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var httpClientKey = puppetest.NewProviderKey[http.Client]()
var taggedKey = puppetest.NewTaggedProviderKey[sql.DB]("readonly")

Engine-Level Providers

Set and retrieve from an engine:

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var cfgKey = puppetest.NewProviderKey[MyConfig]()

cfg := &MyConfig{BaseURL: "http://localhost"}
_ = puppetest.SetProvider(engine, cfgKey, cfg, func(ctx context.Context, c *MyConfig) error {
	return nil
})

cfgPtr, ok := puppetest.Provider[MyConfig](engine, cfgKey)

Factory-Level Providers

Factory providers are stored once, then optionally bound to each newly-created engine.

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var factoryProviderKey = puppetest.NewProviderKey[MyProvider]()
var engineProviderKey = puppetest.NewProviderKey[MyProvider]()

err := puppetest.RegisterFactoryProvider(
	factory,
	factoryProviderKey,
	provider,
	func(ctx context.Context, e *puppetest.Engine, v *MyProvider) error {
		return puppetest.SetProvider(e, engineProviderKey, v, nil)
	},
	func(ctx context.Context, v *MyProvider) error {
		return v.Close(ctx)
	},
)

Resolution API

Any type implementing ProviderResolver can use:

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v, ok := puppetest.ResolveProvider[T](resolver, key)

This is used internally by both engine and factory retrieval helpers.