mesh-catalog/modules/mesh-self-check/cmd/mesh-self-check/main.go

// mesh-self-check: the holder of the seat mesh-self-check (novox/hq ADR 0564 §6). A Go bundle served by a runtime of
// its own, on its own bus account (`runs-as`), so that its account alone writes its buckets: `findings` (what it finds
// wrong now, which the condition keeper raises and clears conditions from), `verdict` (the last run) and `verdicts`
// (every run, kept a week). It runs the probes every five minutes and says `checked` at the end of each run. stdout is
// the MCP channel; what this module says, it says on stderr.
package main

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"time"

	stdio "git.novox.be/novox/mesh-sdk/go"
)

func logf(format string, a ...any) { fmt.Fprintf(os.Stderr, format+"\n", a...) }

// runtimeStore is the bus, through the runtime that launched this bundle.
type runtimeStore struct{}

func (runtimeStore) Get(state, key string) ([]byte, bool, error) {
	e, err := stdio.State(state).Get(key)
	if err != nil || e == nil {
		return nil, false, err
	}
	return e.Value, true, nil
}

func (runtimeStore) Put(state, key string, value any) error {
	_, err := stdio.State(state).Put(key, value)
	return err
}

func (runtimeStore) Delete(state, key string) error { return stdio.State(state).Delete(key) }

func (runtimeStore) Keys(state string) ([]string, error) { return stdio.State(state).Keys() }

// NewChecker is the self-check over the runtime.
func NewChecker() *Checker {
	return &Checker{Store: runtimeStore{}, Registry: Registry(), Now: time.Now, Logf: logf, Host: os.Getenv("MESH_NODE"),
		Enabled: enabledProbes,
		Ask:     func(key string, body any) (json.RawMessage, error) { return stdio.Ask(key, body) },
		Publish: stdio.SeatPublish}
}

func main() {
	c := NewChecker()
	go func() {
		<-stdio.Served()
		c.Keep(context.Background())
	}()
	if err := stdio.Serve("", Tools(c)); err != nil {
		logf("%v", err)
		os.Exit(1)
	}
}

// enabledProbes is the setting `probes`, read at each run so a change applies at the next; with it unreadable, the
// default list.
func enabledProbes() []string {
	raw, err := stdio.Config("probes")
	if err != nil {
		logf("the setting probes cannot be read (%v); the default list runs", err)
		return DefaultProbes
	}
	var list []string
	if json.Unmarshal(raw, &list) != nil {
		logf("the setting probes is not a list of probe ids (%s); the default list runs", raw)
		return DefaultProbes
	}
	return list
}