Module common 

Helper types that can be used by launchers.

Launch Context Type System

The node launch process uses a type-state pattern to ensure correct initialization order at compile time. Methods are only available when their prerequisites are met.

Core Types

• LaunchContext: Base context with executor and data directory
• LaunchContextWith<T>: Context with an attached value of type T
• Attached<L, R>: Pairs values, preserving both previous (L) and new (R) state

Helper Attachments

• WithConfigs: Node config + TOML config
• WithMeteredProvider: Provider factory with metrics
• WithMeteredProviders: Provider factory + blockchain provider
• WithComponents: Final form with all components

Method Availability

Methods are implemented on specific type combinations:

• impl<T> LaunchContextWith<T>: Generic methods available for any attachment
• impl LaunchContextWith<WithConfigs>: Config-specific methods
• impl LaunchContextWith<Attached<WithConfigs, DB>>: Database operations
• impl LaunchContextWith<Attached<WithConfigs, ProviderFactory>>: Provider operations
• etc.

This ensures correct initialization order without runtime checks.

Structs

Attached

Joins two attachments together, preserving access to both values.

LaunchContext

Reusable setup for launching a node.

LaunchContextWith

A LaunchContext along with an additional value.

WithComponents

Helper container to bundle the metered providers container and NodeAdapter.

WithConfigs

Helper container type to bundle the initial NodeConfig and the loaded settings from the reth.toml config

WithMeteredProvider

Helper container type to bundle the ProviderFactory and the metrics sender.

WithMeteredProviders

Helper container to bundle the ProviderFactory, FullNodeTypes::Provider and a metrics sender.