nerdbank-streams/src/QualifiedChannelId.ts

Multiplexing of streams

export interface QualifiedChannelId {
	/**  Gets the channel ID. */
	readonly id: number

	/** Gets a value indicating where the channel originated. */
	readonly source: ChannelSource
}

/**
 * An enumeration of the possible sources of a channel.
 * @description The ordinal values are chosen so as to make flipping the perspective as easy as negating the value,
 * while leaving the Seeded value unchanged.
 */
export enum ChannelSource {
	/** The channel was offered by this MultiplexingStream instance to the other party. */
	// eslint-disable-next-line @typescript-eslint/naming-convention
	Local = 1,

	/** The channel was offered to this MultiplexingStream instance by the other party. */
	// eslint-disable-next-line @typescript-eslint/naming-convention
	Remote = -1,

	/**
	 * The channel was seeded during construction via the Options.SeededChannels collection.
	 * This channel is to be accepted by both parties.
	 */
	// eslint-disable-next-line @typescript-eslint/naming-convention
	Seeded = 0,
}

// tslint:disable-next-line: no-namespace
export namespace QualifiedChannelId {
	export function toString(id: QualifiedChannelId): string {
		const sourceName =
			id.source === ChannelSource.Local
				? 'local'
				: id.source === ChannelSource.Remote
				? 'remote'
				: id.source === ChannelSource.Seeded
				? 'seeded'
				: 'unknown'
		return `${id.id} (${sourceName})`
	}
}