Module log 

Span-tree logging for Jan cron scripts and agent pipelines.

Spans live under logs/ in the store root. Each span is a JSON file logs/<id>.json; log events are embedded in the span they belong to. Reading back a span tree walks the directory and reconstructs parent→child relationships in memory.

Layout:

logs/
  <uuid>.json    # one file per span

Span JSON schema:

{
  "id":         "<uuid>",
  "name":       "fetch-prices",
  "parent_id":  "<uuid> | null",
  "started_at": "<rfc3339>",
  "ended_at":   "<rfc3339> | null",
  "fields":     { "key": "value", ... },
  "events":     [
    { "message": "...", "fields": {...}, "timestamp": "<rfc3339>" }
  ]
}

Structs

LogEvent

A single log event embedded in a span.

Span

A tracing span. Persisted as logs/<id>.json.

Functions

load_all_spans

Load every span from logs/.

log_event

Add a log event to a span.

parse_fields

Parse key=value pairs from a slice of strings.

render_tree

Render a span tree as indented text, starting from roots (or the given span).

span_end

End a span (record ended_at).

span_set_fields

Set key/value fields on an existing span.

span_start

Start a new span, optionally nested under parent_id. Returns the new span’s UUID.