利用 Spring Boot & Redis 实现短链接服务

准备工作

Spring Boot 2.1.0+

Redis

Lombok

Guava 28.0

Common Validator 1.6

添加依赖项

pom.xml

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<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>

<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

<dependency>
<groupId>commons-validator</groupId>
<artifactId>commons-validator</artifactId>
</dependency>

<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
</dependency>
</dependencies>

application.yml

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spring:
# Redis Config
redis:
url: 127.0.0.1
port: 6379
password: your_password

logging:
level:
io.github.y0ngb1n.*: debug

核心代码

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/**
* URL Shortener Resource
*
* @author yangbin
*/
@Slf4j
@RestController
@RequestMapping(path = "/v1")
public class UrlShortenerController {

@Autowired
StringRedisTemplate redisTemplate;

@GetMapping(path = "/{id}")
public String getUrl(@PathVariable String id) {
+ String url = redisTemplate.opsForValue().get(id);
log.debug("URL Retrieved: {}", url);
return url;
}

@PostMapping
public String create(@RequestBody String url) {
UrlValidator urlValidator = new UrlValidator(
new String[]{"http", "https"}
);
if (urlValidator.isValid(url)) {
- String id = Hashing.murmur3_32().hashString(url, StandardCharsets.UTF_8).toString();
log.debug("URL Id generated: {}", id);
+ redisTemplate.opsForValue().set(id, url);
return id;
}
throw new RuntimeException("URL Invalid: " + url);
}
}

使用方式

Step 0: 安装并启动 Redis

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# on Windows
scoop install redis
redis-server

# on Mac
brew install redis
redis-server

Step 1: 启动 url-shortener 服务

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$ mvn install
...
[INFO] BUILD SUCCESS
...
$ mvn spring-boot:run
...
2019-08-21 21:03:50.215 INFO 10244 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path ''
2019-08-21 21:03:50.219 INFO 10244 --- [ main] i.g.y.s.u.UrlShortenerApplication : Started UrlShortenerApplication in 6.01 seconds (JVM running for 12.165)

Step 2: 生成短链

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$ curl -X POST http://127.0.0.1:8080/v1 \
-H 'Content-Type: text/plain' \
-d https://y0ngb1n.github.io
515bbe2b

Step 3: 还原短链

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$ curl -X GET http://127.0.0.1:8080/v1/515bbe2b
https://y0ngb1n.github.io

查看日志

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...
2019-08-21 21:42:26.788 DEBUG 10244 --- [nio-8080-exec-2] i.g.y.s.u.c.UrlShortenerController : URL Id generated: 515bbe2b
2019-08-21 21:42:40.748 DEBUG 10244 --- [nio-8080-exec-3] i.g.y.s.u.c.UrlShortenerController : URL Retrieved: https://y0ngb1n.github.io

参考资料

https://youtu.be/Zr0E2VP24w8

https://en.wikipedia.org/wiki/MurmurHash

https://github.com/google/guava/wiki/HashingExplained

https://www.flyml.net/2016/09/05/cassandra-tutorial-murmurhash/

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