Add support for prorated stripe subs

keycloak/keycloak.go

@@ -3,6 +3,7 @@ package keycloak
 import (
 	"context"
 	"encoding/csv"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -143,6 +144,23 @@ func (k *Keycloak) GetUser(ctx context.Context, userID string) (*User, error) {
 	user.StripeCancelationTime, _ = strconv.ParseInt(safeGetAttr(kcuser, "stripeCancelationTime"), 10, 0)
 	user.StripeETag = safeGetAttr(kcuser, "stripeETag")
 
+	if js := safeGetAttr(kcuser, "paypalMigrationMetadata"); js != "" {
+		s := struct {
+			Price       float64
+			TimeRFC3339 string
+		}{}
+		err := json.Unmarshal([]byte(js), &s)
+		if err != nil {
+			return nil, err
+		}
+
+		user.LastPaypalTransactionPrice = s.Price
+		user.LastPaypalTransactionTime, err = time.Parse(time.RFC3339, s.TimeRFC3339)
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	kuserlogins, err := k.Client.GetUserFederatedIdentities(ctx, token.AccessToken, k.env.KeycloakRealm, *kcuser.ID)
 	if err != nil {
 		return nil, err
@@ -245,6 +263,9 @@ func (k *Keycloak) UpdateUserStripeInfo(ctx context.Context, customer *stripe.Cu
 		return nil
 	}
 
+	// Always clean up any old paypal metadata
+	attr["paypalMigrationMetadata"] = []string{sub.ID}
+
 	if active {
 		attr["stripeID"] = []string{customer.ID}
 		attr["stripeSubscriptionID"] = []string{sub.ID}
@@ -410,6 +431,9 @@ type User struct {
 	StripeSubscriptionID  string
 	StripeCancelationTime int64
 	StripeETag            string
+
+	LastPaypalTransactionPrice float64
+	LastPaypalTransactionTime  time.Time
 }
 
 func safeGetAttrs(kcuser *gocloak.User) map[string][]string {

main.go

@@ -238,7 +238,8 @@ func newStripeCheckoutHandler(env *conf.Env, kc *keycloak.Keycloak, pc *stripeut
 				Quantity: stripe.Int64(1),
 			}}
 			checkoutParams.SubscriptionData = &stripe.CheckoutSessionSubscriptionDataParams{
-				Metadata: map[string]string{"etag": etag},
+				Metadata:           map[string]string{"etag": etag},
+				BillingCycleAnchor: calculateBillingCycleAnchor(user),
 			}
 		}
 		s, err := session.New(checkoutParams)
@@ -388,6 +389,21 @@ func calculateDiscount(user *keycloak.User, priceID string, pc *stripeutil.Price
 	return nil
 }
 
+func calculateBillingCycleAnchor(user *keycloak.User) *int64 {
+	if user.LastPaypalTransactionPrice == 0 {
+		return nil
+	}
+
+	// Annual
+	if user.LastPaypalTransactionPrice > 41 {
+		ts := user.LastPaypalTransactionTime.Add(time.Hour * 24 * 365).Unix()
+		return &ts
+	}
+
+	ts := user.LastPaypalTransactionTime.Add(time.Hour * 24 * 30).Unix()
+	return &ts
+}
+
 // getUserID allows the oauth2proxy header to be overridden for testing.
 func getUserID(r *http.Request) string {
 	user := r.Header.Get("X-Forwarded-Preferred-Username")

templates/profile.html

@@ -45,6 +45,16 @@ <h3 class="panel-title">Payment</h3>
               <a href="/profile/cancel" role="button" class="btn btn-default">Cancel Membership</a>
             </div>
             {{- end }} {{- else }}
+            {{- if .user.LastPaypalTransactionTime }}
+            <div class="alert alert-info" role="alert">
+              We found a Paypal payment associated with your email address from {{
+              .user.LastPaypalTransactionTime.Format "01/02/2006" }}. Your account will be prorated accordingly when
+              signing up with Stripe.<br><br>
+              After signing up, you can cancel your existing Paypal subscription using a link in your latest Paypal
+              receipt
+              email.
+            </div>
+            {{- end }}
             <div class="btn-group" role="group" aria-label="...">
               {{- range .prices }}
               <a href="/profile/stripe?price={{ .ID }}" role="button" class="btn btn-default">{{ .ButtonText }}</a>