
概述
線上項目釋出一般有以下幾種方案:
- 停機釋出
- 藍綠部署
- 滾動部署
- 灰階釋出
這種釋出一般在夜裡或者進行大版本更新的時候釋出,因為需要停機,是以現在大家都在研究
Devops
方案。
藍綠部署需要準備兩個相同的環境。一個環境新版本,一個環境舊版本,通過負載均衡進行切換與復原,目的是為了減少服務停止時間。
滾動部署就是在更新過程中,并不一下子啟動所有新版本,是先啟動一台新版本,再停止一台老版本,然後再啟動一台新版本,再停止一台老版本,直到更新完成。基于
k8s
的更新方案預設就是滾動部署。
灰階釋出也叫金絲雀釋出,灰階釋出中,常常按照使用者設定路由權重,例如90%的使用者維持使用老版本,10%的使用者嘗鮮新版本。不同版本應用共存,經常與A/B測試一起使用,用于測試選擇多種方案。
上邊介紹的幾種釋出方案,主要是引出我們接下來介紹的
spring-cloud-gateway
動态路由,我們可以基于動态路由、負載均衡和政策加載去實作
灰階釋出
。當然現在有很多開源的架構可以實作
灰階釋出
,這裡隻是研究學習。
動态路由
spring-cloud-gateway
預設将路由加載在記憶體中。具體可以參見
InMemoryRouteDefinitionRepository
類的實作。
這裡我們基于
Redis
實作動态路由。基礎項目見 spring-cloud-gateway簡介
1. 将 actuator 的端點暴露出來。
management:
endpoints:
web:
exposure:
include: "*"
2. redis配置
@Configuration
public class RedisConfig {
@Bean(name = {"redisTemplate", "stringRedisTemplate"})
public StringRedisTemplate stringRedisTemplate(RedisConnectionFactory factory) {
StringRedisTemplate redisTemplate = new StringRedisTemplate();
redisTemplate.setConnectionFactory(factory);
return redisTemplate;
}
}
3. 将原記憶體路由持久化到redis
@Component
public class RedisRouteDefinitionRepository implements RouteDefinitionRepository {
/**
* hash存儲的key
*/
public static final String GATEWAY_ROUTES = "gateway_dynamic_route";
@Resource
private StringRedisTemplate redisTemplate;
/**
* 擷取路由資訊
* @return
*/
@Override
public Flux<RouteDefinition> getRouteDefinitions() {
List<RouteDefinition> routeDefinitions = new ArrayList<>();
redisTemplate.opsForHash().values(GATEWAY_ROUTES).stream()
.forEach(routeDefinition -> routeDefinitions.add(JSON.parseObject(routeDefinition.toString(), RouteDefinition.class)));
return Flux.fromIterable(routeDefinitions);
}
@Override
public Mono<Void> save(Mono<RouteDefinition> route) {
return route.flatMap(routeDefinition -> {
redisTemplate.opsForHash().put(GATEWAY_ROUTES, routeDefinition.getId(), JSONObject.toJSONString(routeDefinition));
return Mono.empty();
});
}
@Override
public Mono<Void> delete(Mono<String> routeId) {
return routeId.flatMap(id -> {
if (redisTemplate.opsForHash().hasKey(GATEWAY_ROUTES, id)) {
redisTemplate.opsForHash().delete(GATEWAY_ROUTES, id);
return Mono.empty();
}
return Mono.defer(() -> Mono.error(new NotFoundException("route definition is not found, routeId:" + routeId)));
});
}
}
4. 重寫動态路由服務
@Service
public class GatewayDynamicRouteService implements ApplicationEventPublisherAware {
@Resource
private RedisRouteDefinitionRepository redisRouteDefinitionRepository;
private ApplicationEventPublisher applicationEventPublisher;
/**
* 增加路由
* @param routeDefinition
* @return
*/
public int add(RouteDefinition routeDefinition) {
redisRouteDefinitionRepository.save(Mono.just(routeDefinition)).subscribe();
applicationEventPublisher.publishEvent(new RefreshRoutesEvent(this));
return 1;
}
/**
* 更新
* @param routeDefinition
* @return
*/
public int update(RouteDefinition routeDefinition) {
redisRouteDefinitionRepository.delete(Mono.just(routeDefinition.getId()));
redisRouteDefinitionRepository.save(Mono.just(routeDefinition)).subscribe();
applicationEventPublisher.publishEvent(new RefreshRoutesEvent(this));
return 1;
}
/**
* 删除
* @param id
* @return
*/
public Mono<ResponseEntity<Object>> delete(String id) {
return redisRouteDefinitionRepository.delete(Mono.just(id)).then(Mono.defer(() -> Mono.just(ResponseEntity.ok().build())))
.onErrorResume(t -> t instanceof NotFoundException, t -> Mono.just(ResponseEntity.notFound().build()));
}
@Override
public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
this.applicationEventPublisher = applicationEventPublisher;
}
}
5. 對外暴露接口
@RestController
@RequestMapping("/gateway")
public class GatewayDynamicRouteController {
@Resource
private GatewayDynamicRouteService gatewayDynamicRouteService;
@PostMapping("/add")
public String create(@RequestBody RouteDefinition entity) {
int result = gatewayDynamicRouteService.add(entity);
return String.valueOf(result);
}
@PostMapping("/update")
public String update(@RequestBody RouteDefinition entity) {
int result = gatewayDynamicRouteService.update(entity);
return String.valueOf(result);
}
@DeleteMapping("/delete/{id}")
public Mono<ResponseEntity<Object>> delete(@PathVariable String id) {
return gatewayDynamicRouteService.delete(id);
}
}
測試
測試前删除我們配置的靜态路由,因為靜态路由和redis動态路由同時存在時取并集。
- 通路 http://localhost:2000/actuator/gateway/routes , 可以看到隻有預設路由。
[
{
"route_id": "CompositeDiscoveryClient_consul",
"route_definition": {
"id": "CompositeDiscoveryClient_consul",
"predicates": [
{
"name": "Path",
"args": {
"pattern": "/consul/**"
}
}
],
"filters": [
{
"name": "RewritePath",
"args": {
"regexp": "/consul/(?<remaining>.*)",
"replacement": "/${remaining}"
}
}
],
"uri": "lb://consul",
"order": 0
},
"order": 0
},
{
"route_id": "CompositeDiscoveryClient_idc-gateway",
"route_definition": {
"id": "CompositeDiscoveryClient_idc-gateway",
"predicates": [
{
"name": "Path",
"args": {
"pattern": "/idc-gateway/**"
}
}
],
"filters": [
{
"name": "RewritePath",
"args": {
"regexp": "/idc-gateway/(?<remaining>.*)",
"replacement": "/${remaining}"
}
}
],
"uri": "lb://idc-gateway",
"order": 0
},
"order": 0
},
{
"route_id": "CompositeDiscoveryClient_idc-provider1",
"route_definition": {
"id": "CompositeDiscoveryClient_idc-provider1",
"predicates": [
{
"name": "Path",
"args": {
"pattern": "/idc-provider1/**"
}
}
],
"filters": [
{
"name": "RewritePath",
"args": {
"regexp": "/idc-provider1/(?<remaining>.*)",
"replacement": "/${remaining}"
}
}
],
"uri": "lb://idc-provider1",
"order": 0
},
"order": 0
},
{
"route_id": "CompositeDiscoveryClient_idc-provider2",
"route_definition": {
"id": "CompositeDiscoveryClient_idc-provider2",
"predicates": [
{
"name": "Path",
"args": {
"pattern": "/idc-provider2/**"
}
}
],
"filters": [
{
"name": "RewritePath",
"args": {
"regexp": "/idc-provider2/(?<remaining>.*)",
"replacement": "/${remaining}"
}
}
],
"uri": "lb://idc-provider2",
"order": 0
},
"order": 0
}
]
這個時候通路 http://192.168.124.5:2000/idc-provider1/provider1/1 根據結果可以推測能正确路由到
provider1
, 測試結果一緻。
- 建立
路由,将路徑設定為provider1
,測試是否生效。/p1/**
POST
請求 http://localhost:2000/gateway/add
{
"id":"provider1",
"predicates":[
{
"name":"Path",
"args":{
"_genkey_0":"/p1/**"
}
},
{
"name":"RemoteAddr",
"args":{
"_genkey_0":"192.168.124.5/16"
}
}
],
"filters":[
{
"name":"StripPrefix",
"args":{
"_genkey_0":"1"
}
}
],
"uri":"lb://idc-provider1",
"order":0
}
檢視
redis
存儲,或者請求 http://localhost:2000/actuator/gateway/routes , 都可以看到配置成功。
通路
curl http://localhost:2000/p1/provider1/1
結果輸出2001,與期望一緻。
由此可見動态路由已經生效。
結語
本文到此結束。感興趣的小夥伴後續可以通過加載配置檔案,基于權重進行灰階。歡迎大家關注公衆号【當我遇上你】。