Composable Atmosphere Constellation#

Composable Atmosphere Constellation is a Swift package for reading ATProtocol backlinks from Constellation.

It provides typed request and response models for blue.microcosm.links.getBacklinks, plus helpers that hydrate linked records from the author's PDS. Higher-level packages can use it to discover references across the network without coupling their own domain models to Constellation's raw response shape.

Product#

• ComposableAtmosphereConstellation: Constellation backlink lexicon models, XRPC request helpers, typed record hydration, and small in-flight request coalescing utilities.

Installation#

Add the package to Package.swift:

.package(
  url: "https://source.woody.fm/composable-atmosphere-constellation",
  branch: "main"
)

Then depend on the library product:

.product(
  name: "ComposableAtmosphereConstellation",
  package: "composable-atmosphere-constellation"
)

This package depends on the base ATProto and XRPCClient products from swift-composable-atmosphere and explicitly opts out of its default TCA26 trait.

Usage#

Build a Constellation source from a collection and path:

import ATProto
import ComposableAtmosphereConstellation

let source = Constellation.BacklinkSource(
  collection: "sh.tangled.repo.pull",
  path: "target.repo"
)

Fetch backlinks for a DID or record URI:

import XRPCClient

guard let repo = DID("did:plc:repo") else {
  return
}

let backlinks = try await XRPC.Client.liveValue.constellationGetBacklinks(
  subject: repo,
  source: source,
  limit: 25
)

For typed record hydration, conform the referenced record value to Constellation.BacklinkedRecordValue and call constellationGetBacklinkedRecords.

Development#

Run the package checks with:

swift build && swift test