我们在gateway服务
中,创建一个拦截器;在拦截器中,向后续服务传递自定义header头信息。
拦截器定义如下:
@Configuration
public class TestGlobalFilter implements GlobalFilter, Ordered {
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
// .....
// 封装需要向后续封装的header对象
LinkedHashMap<String, String> headerMap = new LinkedHashMap<>();
headerMap.put("header1", "1");
headerMap.put("header2", "2");
headerMap.put("header3", "3");
chainFilterAndSetHeaders(chain, exchange, headerMap);
// .....
//调用chain.filter继续向下游执行
return chain.filter(exchange);
}
/**
* 顺序,数值越小,优先级越高
*
* @return
*/
@Override
public int getOrder() {
return 1;
}
/**
* 设置向后传递的header
*
* @param chain
* @param exchange
* @param headerMap
*/
private Mono<Void> chainFilterAndSetHeaders(GatewayFilterChain chain, ServerWebExchange exchange, LinkedHashMap<String, String> headerMap) {
// 添加header
Consumer<HttpHeaders> httpHeaders = httpHeader -> {
for (Map.Entry<String, String> entry : headerMap.entrySet()) {
// 遍历Map设置header,向后传递
httpHeader.set(entry.getKey(), entry.getValue());
}
};
ServerHttpRequest newRequest = exchange.getRequest().mutate().headers(httpHeaders).build();
ServerWebExchange build = exchange.mutate().request(newRequest).build();
//将现在的request 变成 exchange对象
return chain.filter(build);
}
}
应用:
在下游服务的拦截器中,可以通过request.getHeader()
获取从gateway
。