java 39 lines · 6 steps

Swapping payment gateways by profile in Spring

One config class defines three PaymentGateway beans, and the active Spring profile picks exactly which one loads.

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Spring Intermediate dependency-injection profiles configuration environment-config beans
1package com.example.payments.config;
2 
3import com.stripe.StripeClient;
4import org.springframework.beans.factory.annotation.Value;
5import org.springframework.context.annotation.Bean;
6import org.springframework.context.annotation.Configuration;
7import org.springframework.context.annotation.Profile;
8 
9@Configuration
10public class PaymentGatewayConfig {
11 
12 @Bean
13 @Profile("local")
14 public PaymentGateway sandboxPaymentGateway() {
15 return new StubPaymentGateway();
16 }
17 
18 @Bean
19 @Profile("staging")
20 public PaymentGateway stagingPaymentGateway(
21 @Value("${stripe.test-key}") String testKey) {
22 StripeClient client = StripeClient.builder()
23 .setApiKey(testKey)
24 .build();
25 return new StripePaymentGateway(client, false);
26 }
27 
28 @Bean
29 @Profile("production")
30 public PaymentGateway livePaymentGateway(
31 @Value("${stripe.live-key}") String liveKey,
32 @Value("${stripe.webhook-secret}") String webhookSecret) {
33 StripeClient client = StripeClient.builder()
34 .setApiKey(liveKey)
35 .setConnectTimeout(5_000)
36 .build();
37 return new StripePaymentGateway(client, true, webhookSecret);
38 }
39}
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1Binding beans to profiles lets one interface resolve to different implementations per environment without conditional code.
  2. 2Injecting secrets through @Value keeps keys out of source and scoped to the environment that needs them.
  3. 3A stub implementation for local development removes any dependency on live external services.

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