pzp-dict/protospec.md

2.5 KiB

Feed tangle

(Lipmaa backlinks are not shown in the diagram below, but they should exist)

graph RL

R["(Feed root)"]
A[updates age]
B[updates name]
C[updates age]
D[updates name]
E[updates age & name]

C-->B-->A-->R
D--->A
E-->D & C
classDef default fill:#bbb,stroke:#fff0,color:#000

Reducing the tangle above in a topological sort allows you to build a dict (a JSON object) {age, name}.

Msg metadata domain

msg.metadata.domain MUST start with dict_v1__. E.g. dict_v1__profile.

Msg data

msg.data format:

interface MsgData {
  update: {
    [field in string]: any,
  },
  supersedes: Array<MsgHash>,
}

RECOMMENDED that the msg.data.update is as flat as possible (no nesting).

When you update a field in a dict, in the supersedes array you MUST point to the currently-known highest-depth msg that updated that field.

The set of not-transitively-superseded-by-anyone msgs comprise the "field roots" of the dict. To allow pruning the tangle, we can delete (or, if we want to keep metadata, "erase") all msgs preceding the field roots.

Suppose the tangle is grown in the order below, then the field roots are highlighted in blue.

graph RL

R["(Feed root)"]
A[updates age]:::blue
A-->R
classDef default fill:#bbb,stroke:#fff0,color:#000
classDef blue fill:#6af,stroke:#fff0,color:#000

graph RL

R["(Feed root)"]
A[updates age]:::blue
B[updates name]:::blue
B-->A-->R
classDef default fill:#bbb,stroke:#fff0,color:#000
classDef blue fill:#6af,stroke:#fff0,color:#000

graph RL

R["(Feed root)"]
A[updates age]
B[updates name]:::blue
C[updates age]:::blue

C-->B-->A-->R
C-- supersedes -->A

linkStyle 3 stroke-width:1px,stroke:#05f
classDef default fill:#bbb,stroke:#fff0,color:#000
classDef blue fill:#6af,stroke:#fff0,color:#000

graph RL

R["(Feed root)"]
A[updates age]
B[updates name]:::blue
C[updates age]:::blue
D[updates name]:::blue

C-->B-->A-->R
D--->A
C-- supersedes -->A

linkStyle 4 stroke-width:1px,stroke:#05f
classDef default fill:#bbb,stroke:#fff0,color:#000
classDef blue fill:#6af,stroke:#fff0,color:#000

graph RL

R["(Feed root)"]
A[updates age]
B[updates name]
C[updates age]
D[updates name]
E[updates age & name]:::blue

C-->B-->A-->R
C-- supersedes -->A
D-->A
E-->D & C
E-- supersedes -->C
E-- supersedes -->D

linkStyle 3,7,8 stroke-width:1px,stroke:#05f
classDef default fill:#bbb,stroke:#fff0,color:#000
classDef blue fill:#6af,stroke:#fff0,color:#000