admins.gno

 1// Package admins lets a fixed set of addresses change a realm's gnotif
 2// triggers. The realm passes the handle gnotif.Open returned straight to New,
 3// keeps the *Admins unexported, and on each call gives its gnotif identity,
 4// minted in the crossing function the admin called.
 5package admins
 6
 7import (
 8	"chain/runtime"
 9	"strings"
10
11	"gno.land/p/nym-gfanton001/gnotif/trigger/v0"
12)
13
14// Handle is the method set of the registry's *Handle.
15type Handle interface {
16	Set(cur realm, name string, t trigger.Trigger) string
17	Remove(cur realm, name string)
18}
19
20// Admins holds a realm's handle and the addresses allowed to use it.
21type Admins struct {
22	h      Handle
23	admins map[address]bool
24}
25
26// New returns an Admins over the handle h. It panics with no admin.
27func New(h Handle, addrs ...address) *Admins {
28	if len(addrs) == 0 {
29		panic("at least one admin")
30	}
31	a := &Admins{h: h, admins: make(map[address]bool, len(addrs))}
32	for _, addr := range addrs {
33		if !addr.IsValid() {
34			panic("invalid admin address " + addr.String())
35		}
36		// A caller's address is lower case; bech32 also allows upper case.
37		a.admins[address(strings.ToLower(string(addr)))] = true
38	}
39	return a
40}
41
42// Set stores t under name and returns its id, when the realm's caller is an
43// admin. me is the realm's gnotif identity, cur.Sub(gnotif.Subpath), and its
44// Previous is the caller.
45func (a *Admins) Set(_ int, me realm, name string, t trigger.Trigger) string {
46	a.mustAdmin(0, me)
47	return a.h.Set(cross(me), name, t)
48}
49
50// Remove removes the trigger under name, when the realm's caller is an admin.
51func (a *Admins) Remove(_ int, me realm, name string) {
52	a.mustAdmin(0, me)
53	a.h.Remove(cross(me), name)
54}
55
56func (a *Admins) mustAdmin(_ int, me realm) {
57	if !me.IsCurrent() {
58		panic("me is not current: mint it in the crossing function the admin called")
59	}
60	if _, _, _, isSession := runtime.GetSessionInfo(); isSession {
61		panic("sign with your own key, not a session key")
62	}
63	if caller := me.Previous().Address(); !a.admins[caller] {
64		panic(caller.String() + " is not an admin")
65	}
66}