Lab · Cross-Mesh Subscription

In this lab you will author a complete cross-mesh subscription, a DIDComm message envelope, and a family-channel comparison — then validate the YAML with the pico CLI.

Setup

mkdir -p scratch/mesh

Step 1 — Subscription configuration

Create scratch/mesh/subscription-a-b.yaml:

# scratch/mesh/subscription-a-b.yaml
subscription:
  initiator:
    id: oep.pico.alice
    did: did:webvh:https://engine-a.example.com/picos/alice
    peer: did:peer:rel-alice-bob
  recipient:
    id: oep.pico.bob
    did: did:webvh:https://engine-b.example.com/picos/bob
    peer: did:peer:rel-bob-alice
  handshake: didcomm-introduction-v1

Step 2 — DIDComm message envelope

Create scratch/mesh/message-a-to-b.yaml:

# scratch/mesh/message-a-to-b.yaml
message:
  from: did:peer:rel-alice-bob
  to: did:peer:rel-bob-alice
  type: pico/query
  body:
    query: get-status
    request-id: req-001

Step 3 — Family channel comparison

Create scratch/mesh/family-channel.yaml:

# scratch/mesh/family-channel.yaml
family:
  parent:
    id: oep.pico.root
    eci: eci:root-family
  child:
    id: oep.pico.alice
    eci: eci:alice-family
  transport: local

Step 4 — Validate all three

pico parse scratch/mesh/subscription-a-b.yaml --out /tmp/s1.json \
  && echo "OK: subscription parses"
pico parse scratch/mesh/message-a-to-b.yaml --out /tmp/s2.json \
  && echo "OK: DIDComm envelope parses"
pico parse scratch/mesh/family-channel.yaml --out /tmp/s3.json \
  && echo "OK: family channel parses"

Step 5 — Compare

Answer, using your files:

Which file uses a did:webvh, and for what purpose?
Which file uses did:peer, and why?
Which file uses an ECI, and what kind of relationship does it model?

What you will produce

A subscription config, a DIDComm envelope, and a family-channel config that together demonstrate the three identity/addressing mechanisms and the two relationship classes.

Continue with the Summary.