Layr8.Mediation (layr8 v0.3.3)

Store-and-forward for an agent that is not always connected, against a DIDComm mediator (layr8/mediator): coordinate-mediation/3.0 enrolment, messagepickup/3.0 collection, and the cloud-node's mediator declaration.

The cloud-node deposits any message that arrives while this agent's plugin is offline with the mediator the agent has declared on its node (PUT /api/v1/dids/:did/mediator, cloud-node ADR 0005). What the mediator holds is the original ciphertext, so collecting it means posting each attachment back to this agent's own node at /didcomm, where it is unpacked, sender-bound and authorized exactly like a first arrival, and then delivered to this client's handlers. Nothing here ever decrypts.

Zero-config use

Give the client a mediator and it does the rest on every (re)connect:

Layr8.Client.start_link(%{mediator: "did:web:node.example:agents:mediator"})

(or LAYR8_MEDIATOR_DID). The client then, in the background:

enroll/3 — mediate-request, then recipient-update adding its own DID;
declare/3 — tells its node to route offline messages to the mediator;
pickup/3 — pulls everything queued, re-injects it, acknowledges;
live/4 — turns live delivery on (unless mediator_live: false), so later forwards are pushed as delivery messages, which the client re-injects and acknowledges the same way.

Every step is also callable by hand, and none of them raises.

Grants

The agent needs protocol grants on the mediator resource for coordinate-mediation/3.0 and messagepickup/3.0 (issued in the portal). Forwards to the mediator, including the ones the node builds, are open deposits and need no grant.

Summary

Types

client()

Functions

bootstrap(client, mediator, opts \\ [])

enroll/3 → declare/3 → pickup/3 → live/4 (when opts[:live], default true), logging and stopping at the first failure. Never raises.

collect(client, mediator, attachments, opts \\ [])

Re-injects attachments through this agent's node and acknowledges the ones that went in. Returns {:ok, count, :complete | :partial}.

declare(client, mediator, opts \\ [])

Declares mediator as this agent's mediator on its own cloud-node, so the node deposits messages there while the agent is offline and the DID document advertises it as routingKeys.

delivery_type()

The message type the client handles for live pushes.

enroll(client, mediator, opts \\ [])

Requests mediation and registers this agent's DID (plus opts[:recipients]) with mediator.

live(client, mediator, flag, opts \\ [])

Turns live delivery on or off. Returns the mediator's status body.

pickup(client, mediator, opts \\ [])

Drains the mediator: repeats delivery-request (opts[:limit], default 10) until a status reply, re-injecting every attachment through this agent's node and acknowledging what was re-injected.

protocol_bases()

Protocol bases a mediated client subscribes to.

reinject(client, attachments, opts \\ [])

Posts each attachment's ciphertext (data.base64, base64url) to this agent's node at /didcomm. Returns {re-injected ids, failed ids}. Attachments without ciphertext are counted as failed and never acknowledged.

status(client, mediator, opts \\ [])

Asks the mediator how many messages are waiting.

undeclare(client, opts \\ [])

Removes this agent's mediator declaration on its node.

Types

client()

@type client() :: pid()

Functions

bootstrap(client, mediator, opts \\ [])

@spec bootstrap(client(), String.t(), keyword()) :: :ok | {:error, {atom(), term()}}

enroll/3 → declare/3 → pickup/3 → live/4 (when opts[:live], default true), logging and stopping at the first failure. Never raises.

collect(client, mediator, attachments, opts \\ [])

@spec collect(client(), String.t(), [Layr8.Attachment.t()], keyword()) ::
  {:ok, non_neg_integer(), :complete | :partial}

Re-injects attachments through this agent's node and acknowledges the ones that went in. Returns {:ok, count, :complete | :partial}.

declare(client, mediator, opts \\ [])

@spec declare(client(), String.t(), keyword()) :: :ok | {:error, term()}

Declares mediator as this agent's mediator on its own cloud-node, so the node deposits messages there while the agent is offline and the DID document advertises it as routingKeys.

delivery_type()

@spec delivery_type() :: String.t()

The message type the client handles for live pushes.

enroll(client, mediator, opts \\ [])

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

Requests mediation and registers this agent's DID (plus opts[:recipients]) with mediator.

Returns {:ok, %{routing_did: [..], updated: [..]}}. Idempotent: a second call re-receives the grant and gets no_change on the registrations. {:error, :mediate_denied} when the mediator refuses; {:error, {:recipient_update, entries}} when the agent's own DID could not be registered (someone else's routing key, or the mediator's keylist policy).

live(client, mediator, flag, opts \\ [])

@spec live(client(), String.t(), boolean(), keyword()) ::
  {:ok, map()} | {:error, term()}

Turns live delivery on or off. Returns the mediator's status body.

pickup(client, mediator, opts \\ [])

@spec pickup(client(), String.t(), keyword()) ::
  {:ok, non_neg_integer()} | {:error, term()}

Drains the mediator: repeats delivery-request (opts[:limit], default 10) until a status reply, re-injecting every attachment through this agent's node and acknowledging what was re-injected.

Returns {:ok, count} of messages re-injected. An attachment whose re-injection failed is left queued (not acknowledged) and the loop stops, so nothing is lost and nothing is retried forever.

protocol_bases()

@spec protocol_bases() :: [String.t()]

Protocol bases a mediated client subscribes to.

reinject(client, attachments, opts \\ [])

@spec reinject(client(), [Layr8.Attachment.t()], keyword()) ::
  {[String.t()], [String.t()]}

status(client, mediator, opts \\ [])

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

Asks the mediator how many messages are waiting.

undeclare(client, opts \\ [])

@spec undeclare(
  client(),
  keyword()
) :: :ok | {:error, term()}

Removes this agent's mediator declaration on its node.