nginx 配置文件中的 location 有什么问题？

我已经使用 dockerfile 创建并启动了带有 echo 模块的 nginx：

FROM nginx:1.16.1-alpine AS builder

RUN wget "http://nginx.org/download/nginx-${NGINX_VERSION}.tar.gz" -O nginx.tar.gz && \
  wget "https://github.com/openresty/echo-nginx-module/archive/v0.62.tar.gz" -O echo-   nginx-module-0.62.tar.gz

RUN apk add --no-cache --virtual .build-deps \
    gcc \
    libc-dev \
    make \
    openssl-dev \
    pcre-dev \
    zlib-dev \
    linux-headers \
    libxslt-dev \
    gd-dev \
    geoip-dev \
    perl-dev \
    libedit-dev \
    mercurial \
    bash \
    alpine-sdk \
    findutils

SHELL ["/bin/ash", "-eo", "pipefail", "-c"]

RUN rm -rf /usr/src/nginx && mkdir -p /usr/src/nginx /usr/src/echo-nginx-module-0.62 && \
    tar -zxC /usr/src/nginx -f nginx.tar.gz && \
    tar -xzC /usr/src/echo-nginx-module-0.62 -f echo-nginx-module-0.62.tar.gz

WORKDIR /usr/src/nginx/nginx-${NGINX_VERSION}

RUN CONFARGS=$(nginx -V 2>&1 | sed -n -e 's/^.*arguments: //p') &&  \
    sh -c "./configure --with-compat $CONFARGS --add-dynamic-module=/usr/src/echo-nginx-module-0.62/*" && \
make modules

FROM nginx:1.16.1-alpine

COPY --from=builder /usr/src/nginx/nginx-${NGINX_VERSION}/objs/*_module.so /etc/nginx/modules/

COPY nginx.conf /etc/nginx/nginx.conf

CMD ["nginx", "-g", "daemon off;"]

此外，我有一个合适(我猜)的 nginx.conf:

worker_processes 1;

load_module /etc/nginx/modules/ngx_http_echo_module.so;

events {
    worker_connections  1024;
}

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    access_log  off;
    sendfile        on;
    tcp_nopush      on;

    keepalive_timeout  65;

    include /etc/nginx/conf.d/*.conf;

    server {
        listen       80;
        server_name  myhost.com;

        location /echo_after_sleep {
        default_type text/plain;
            echo_sleep 1.234;
            echo "resumed!";
        }
    }
}

我正在尝试访问 http://localhost/echo\_after\_sleep，期望得到一个延迟响应 "resumed!"，但是有些东西出了问题... 有人能帮我弄清楚我做错了什么吗？