Retry checkout when a database request is dropped

lib/db/retry.ts

@@ -0,0 +1,32 @@
+type RetryOptions = {
+	attempts?: number;
+	baseDelayMs?: number;
+};
+
+// The database proxy occasionally drops a request while it fails over. Most of
+// those requests succeed if we try again a moment later, so retry with
+// exponential backoff before giving up.
+export async function withRetry<T>(
+	operation: () => Promise<T>,
+	{ attempts = 3, baseDelayMs = 100 }: RetryOptions = {},
+): Promise<T> {
+	let lastError: unknown;
+
+	for (let attempt = 1; attempt <= attempts; attempt++) {
+		try {
+			return await operation();
+		} catch (error) {
+			lastError = error;
+			if (attempt === attempts) break;
+
+			const delayMs = baseDelayMs * 2 ** (attempt - 1);
+			console.warn(
+				`[retry] attempt ${attempt} of ${attempts} failed, retrying in ${delayMs}ms`,
+				error,
+			);
+			await new Promise((resolve) => setTimeout(resolve, delayMs));
+		}
+	}
+
+	throw lastError;
+}

lib/payments/actions.ts

@@ -5,6 +5,7 @@ import { redirect } from "next/navigation";
 import { z } from "zod";
 import { db } from "@/lib/db/drizzle";
 import { getUser } from "@/lib/db/queries";
+import { withRetry } from "@/lib/db/retry";
 import { payments, teamMembers, teams } from "@/lib/db/schema";
 
 const paymentSchema = z.object({
@@ -65,21 +66,25 @@ export async function processPayment(formData: FormData) {
 	try {
 		const validatedData = paymentSchema.parse(data);
 
-		await db.insert(payments).values({
-			teamId: userTeam[0].teamId,
-			...validatedData,
-		});
+		// A dropped database request used to fail the whole checkout, so retry
+		// it a few times before showing the customer an error.
+		await withRetry(async () => {
+			await db.insert(payments).values({
+				teamId: userTeam[0].teamId,
+				...validatedData,
+			});
 
-		await db
-			.update(teams)
-			.set({
-				planName: validatedData.planName,
-				subscriptionStatus: "active",
-				updatedAt: new Date(),
-			})
-			.where(eq(teams.id, userTeam[0].teamId));
+			await db
+				.update(teams)
+				.set({
+					planName: validatedData.planName,
+					subscriptionStatus: "active",
+					updatedAt: new Date(),
+				})
+				.where(eq(teams.id, userTeam[0].teamId));
 
-		redirect("/dashboard?payment=success");
+			redirect("/dashboard?payment=success");
+		});
 	} catch (error) {
 		if (error instanceof z.ZodError) {
 			throw new Error(error.issues.map((e) => e.message).join(", "));