ProtoRune.Atproto.Sync (proto_rune v0.5.1)

Low-level com.atproto.sync read operations.

These are public PDS endpoints: no session and no auth headers are involved. Every function takes the base URL of the origin PDS as its first argument (the bare URL or the /xrpc-suffixed one; it is normalized internally), so the caller explicitly targets the PDS that hosts the repository.

get_repo/2 returns the repository as a CAR (Content Addressable aRchive) file. Use parse_car/1 to decode it into a map of ProtoRune.CID => decoded block, and ProtoRune.MST to enumerate the records it contains.

Trust model

Checkouts are trusted against the source PDS: no commit or signature verification is performed. If you cannot trust the PDS you are reading from, verify the commit chain yourself before consuming the data.

Examples

{:ok, %{content_type: _, body: car}} =
  Sync.get_repo("https://pds.example.com", "did:plc:ewvi7nxzyoun6zhxrhs64oiz")

{:ok, blocks} = Sync.parse_car(car)

Summary

Functions

describe_repo(pds_url, repo)

Get information about an account's repository, including its current head commit. repo is a handle or a DID. Does not require auth, implemented by PDS.

get_blob(pds_url, did, cid)

Get a single blob from a repository, for example an image attached to a record. Does not require auth, implemented by PDS.

get_repo(pds_url, did)

Download a repository checkout as a CAR file. Does not require auth, implemented by PDS.

parse_car(data)

Decodes a repository CAR into its blocks.

Functions

describe_repo(pds_url, repo)

@spec describe_repo(String.t(), String.t()) :: {:ok, map()} | {:error, term()}

Get information about an account's repository, including its current head commit. repo is a handle or a DID. Does not require auth, implemented by PDS.

https://docs.bsky.app/docs/api/com-atproto-sync-describe-repo

get_blob(pds_url, did, cid)

@spec get_blob(String.t(), String.t(), String.t()) ::
  {:ok, %{content_type: String.t() | nil, body: binary()}} | {:error, term()}

Get a single blob from a repository, for example an image attached to a record. Does not require auth, implemented by PDS.

Returns {:ok, %{content_type: content_type, body: body}} with the raw blob bytes and the content type reported by the server (nil when the response carries no content-type header).

https://docs.bsky.app/docs/api/com-atproto-sync-get-blob

get_repo(pds_url, did)

@spec get_repo(String.t(), String.t()) ::
  {:ok, %{content_type: String.t() | nil, body: binary()}} | {:error, term()}

Download a repository checkout as a CAR file. Does not require auth, implemented by PDS.

Returns {:ok, %{content_type: content_type, body: car}} where car is the raw CAR byte string; decode it with parse_car/1.

https://docs.bsky.app/docs/api/com-atproto-sync-get-repo

parse_car(data)

@spec parse_car(binary() | {:ok, %{body: binary()}}) ::
  {:ok, %{required(ProtoRune.CID.t()) => term()}} | {:error, atom() | tuple()}

Decodes a repository CAR into its blocks.

Accepts either the raw CAR binary or the {:ok, %{body: car}} tuple returned by get_repo/2, and returns {:ok, blocks} where blocks is a map of ProtoRune.CID => DAG-CBOR decoded block. CID links inside decoded blocks keep their raw {:tag, 42, bytes} form and can be turned into ProtoRune.CID values with ProtoRune.CID.from_link/1.

The CAR header's root CIDs (which identify the signed commit block) are not part of the returned map; read them with ProtoRune.CAR.read/1 when needed. Pass the commit block's data CID to ProtoRune.MST.entries/2 to enumerate the records of the checkout.