JIP-1: Debug message host call

A host call for passing a debugging message from the service/authorizer to the hosting environment for logging to the node operator.

Host-call specification

Index: 100
Name: log
Gas usage: 0
Input registers:

${\omega }_{7\cdots +5}$
Output registers:

$\{\}$

• level =
  ${\omega }_7$
• target =
  $\{\begin{array}{ll}\varnothing & \text{when }{\omega }_8=0\wedge {\omega }_9=0\\ {\mu }_{{\omega }_8\cdots +{\omega }_9}& \text{otherwise}\end{array}$
• message =
  ${\mu }_{{\omega }_{10}\cdots +{\omega }_{11}}$

Side-effects

No side-effects if memory access is invalid.

Otherwise, express a message to user according to the user-agent.

Suggestions & examples

Levels definition

• 0: User agent displays as fatal error ⛔️
• 1: User agent displays as warning ⚠️
• 2: User agent displays as important information ℹ️
• 3: User agent displays as helpful information 💁
• 4: User agent displays as pedantic information 🪡

Display format for console logging

Note that <CORE> is assumed to be the integer index of the core on which the PVM is executing, which may not exist (e.g. in the On-Transfer logic).

Note that <SERVICE_ID> is assumed to be the integer index of the service for which the PVM is executing, which may not exist (e.g. in the Is-Authorized logic).

<YYYY-MM-DD hh-mm-ss> <LEVEL>[@<CORE>]?[#<SERVICE_ID>]? [<TARGET>]? <MESSAGE>

Example log item

2025/01/01 12:10:42 DEBUG@1#42 bootstrap-refine Hello world!

Format for JSON logging

{
    "time": "<YYYY-MM-DD hh-mm-ss>",
    "level": "<LEVEL>",
    "message": "<MESSAGE>",
    "target": "<TARGET>" | null
    "service": "<SERVICE_ID>" | null
    "core": "<CORE>" | null
}