feat(examples): add subscriptions package #4931

MikaelVallenet · 2025-12-01T17:49:23Z

a package that handle subscriptions either with native coins or grc20 coins.
a public API with a way to create service where users can subscribe and top up their account.
Services owners can check the status of a user subscription to give access or not to a service.

The coins part is from payrolls realm available here: #3432
I added unit test for the coins handling part that is the most "critical" one.

⚠️ This realm is set to private to allow upgrade without proxy pattern and is meant to be an example of what is possible not developed in a production goal, for now at least

Gno2D2 · 2025-12-01T17:49:58Z

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codecov · 2025-12-01T18:01:04Z

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…net/gno into mikael/feat/subscription-pkg

Davphla

I think we should:

Add a README for explaining what the realm is about + main public function
Add a dashboard in the UI to explain how to use the service (Exemple: add subscription)
(I can do a PR for this additions)
You should add events for important operation
There's some inconsistency, when sometime you use panic(...) and sometimes panic(errors.New(...))

Davphla · 2025-12-06T08:01:32Z

examples/gno.land/r/samcrew/subscriptions/coins.gno

+// XXX: this part is 100% from payrolls realm from N0izN0iz <3
+// Payrolls realm: https://github.com/gnolang/gno/pull/3432
+
+// Coins transforms coins into subscriptions coins, prefixing their denom them with their type. Examples: "ugnot" -> "/native/ugnot", "gno.land/r/demo/foo20" -> "/grc20/gno.land/r/demo/foo20"


I think this should be move to its own standalone package
/p/samcrew/coins/normalizedCoins.gno
Or something like that

Davphla · 2025-12-06T08:20:03Z

examples/gno.land/r/samcrew/subscriptions/coins.gno

+
+func sendCoins(dst address, coins chain.Coins) {
+	if len(coins) == 0 {
+		return


Instead of returning silently, we should return an error, a status or a panic

Davphla · 2025-12-06T08:25:04Z

examples/gno.land/r/samcrew/subscriptions/render.gno

+	return ""
+}
+
+func humanDuration(d time.Duration) string {


This should be moved to its own package. This may be useful in other situations.
Maybe we can create /p/samcrew/renderutils, and add more later on.

Davphla · 2025-12-06T08:33:15Z

examples/gno.land/r/samcrew/subscriptions/coins.gno

+		out[j].Amount = coin.Amount
+		out[j].Denom = "/grc20/" + coin.Denom
+	}
+	return out, nil


error is always == to nil
If both len == 0, we should return an error

Davphla · 2025-12-06T08:36:38Z

examples/gno.land/r/samcrew/subscriptions/coins.gno

+// Payrolls realm: https://github.com/gnolang/gno/pull/3432
+
+// Coins transforms coins into subscriptions coins, prefixing their denom them with their type. Examples: "ugnot" -> "/native/ugnot", "gno.land/r/demo/foo20" -> "/grc20/gno.land/r/demo/foo20"
+func Coins(cur realm, native chain.Coins, grc20 chain.Coins) (chain.Coins, error) {


Suggested change

func Coins(cur realm, native chain.Coins, grc20 chain.Coins) (chain.Coins, error) {

func PrefixCoins(cur realm, native chain.Coins, grc20 chain.Coins) (chain.Coins, error) {

Or NormalizeCoins, FormatCoins

Davphla · 2025-12-07T06:53:23Z