at-container-registry/pkg/billing/tier_resolution_testmode_test.go

//go:build billing && testmode

package billing

import (
	"encoding/json"
	"fmt"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"atcr.io/pkg/testpds"
	"github.com/bluesky-social/indigo/atproto/atcrypto"
	"github.com/stripe/stripe-go/v84"
)

// managedHoldServer starts an httptest server standing in for a managed hold
// and returns it with the did:web the tier fan-out resolves back to it. The
// server serves its own DID document at /.well-known/did.json; handler gets
// every other request. Resolving a loopback did:web needs a `-tags testmode`
// build, which this file's build constraint guarantees.
func managedHoldServer(t *testing.T, handler http.HandlerFunc) (*httptest.Server, string) {
	t.Helper()
	mux := http.NewServeMux()
	mux.HandleFunc("/.well-known/did.json", func(w http.ResponseWriter, r *http.Request) {
		base := "http://" + r.Host
		testpds.HoldDIDDocumentHandler(testpds.DIDWebForURL(base), base)(w, r)
	})
	mux.Handle("/", handler)
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)
	return srv, testpds.DIDWebForURL(srv.URL)
}

// TestHandleSubscriptionChange_GrandfatheredSubscriberKeepsTier runs the same
// property through the real webhook path, so it covers the payload shape too:
// Stripe sends price.product as a bare ID string, and this fails if that is
// ever read wrongly.
//
// It asserts on the rank the managed hold is actually asked to apply. An
// earlier draft asserted that the event was recorded as processed, and passed
// against price-only resolution — because an unresolved tier ALSO records the
// event and returns nil. That is the defect itself, so any assertion it
// satisfies cannot be measuring the fix.
func TestHandleSubscriptionChange_GrandfatheredSubscriberKeepsTier(t *testing.T) {
	const secret = "whsec_grandfather_test"
	m, _ := newTestManager(t, secret)
	m.cfg.Tiers = tierTestConfig().Tiers

	stripeAPIReturning(t, http.StatusOK,
		`{"id":"cus_gf","object":"customer","metadata":{"user_did":"did:plc:grandfathered"}}`)

	type tierPush struct {
		UserDID  string `json:"userDid"`
		TierRank int    `json:"tierRank"`
	}
	pushes := make(chan tierPush, 4)
	_, holdDID := managedHoldServer(t, func(w http.ResponseWriter, r *http.Request) {
		var got tierPush
		_ = json.NewDecoder(r.Body).Decode(&got)
		pushes <- got
		w.WriteHeader(http.StatusOK)
	})
	m.managedHolds = []string{holdDID}

	priv, err := atcrypto.GeneratePrivateKeyP256()
	if err != nil {
		t.Fatalf("generate key: %v", err)
	}
	m.privateKey = priv

	// price_supporter_v1_retired appears nowhere in the config. Only its
	// product does — this is the subscriber a price change left behind.
	payload := fmt.Sprintf(`{
		"id": "evt_grandfathered",
		"object": "event",
		"api_version": %q,
		"type": "customer.subscription.updated",
		"created": %d,
		"data": {"object": {
			"id": "sub_gf",
			"object": "subscription",
			"status": "active",
			"customer": "cus_gf",
			"items": {"object":"list","data":[{"price":{
				"id":"price_supporter_v1_retired",
				"product":"prod_supporter"
			}}]}
		}}
	}`, stripe.APIVersion, time.Now().Unix())

	if err := postWebhook(t, m, secret, []byte(payload)); err != nil {
		t.Fatalf("webhook: %v", err)
	}

	select {
	case got := <-pushes:
		if got.TierRank != 1 {
			t.Errorf("hold was asked for tierRank %d, want 1 (supporter)", got.TierRank)
		}
		if got.UserDID != "did:plc:grandfathered" {
			t.Errorf("hold was asked to update %q, want did:plc:grandfathered", got.UserDID)
		}
	case <-time.After(2 * time.Second):
		t.Fatal("no tier push reached the hold — the grandfathered subscriber's tier was never applied")
	}
}