球童无法识别环境变量

Question

我在 docker 中使用 caddy 服务器来反向代理到我的 Nodejs 服务器。我正在传递

UPSTREAMS

env var，如Here所述。但 UPSTREAMS 不被球童认可。如果我在 Caddyfile 中对 UPSTREAMS 进行硬编码，reverse_proxy 就可以正常工作。

Dockerfile

# https://caddyserver.com/docs/build#docker

FROM caddy:2.8.4-builder AS builder

RUN xcaddy build \
    --with github.com/mholt/caddy-ratelimit

FROM caddy:2.8.4

COPY --from=builder /usr/bin/caddy /usr/bin/caddy

docker-compose.yaml

services:
  # https://caddyserver.com/docs/running#setup
  caddy:
    build:
      context: .
      dockerfile: Dockerfile.caddy
    container_name: caddy
    restart: unless-stopped
    environment:
      - DOMAIN=${DOMAIN:-http://localhost:80}
      - CERT_EMAIL=$CERT_EMAIL
      - UPSTREAMS="node-server-1:5000 node-server-2:5000"
    volumes:
      - ./Caddyfile:/etc/caddy/Caddyfile
      - ./caddy_data:/data
      - ./caddy_config:/config
    ports:
      - 80:80
      - 443:443

还有我的 Caddyfile

{
    email {$CERT_EMAIL}
    # https://github.com/mholt/caddy-ratelimit?tab=readme-ov-file#caddyfile-config
    order rate_limit before basicauth

    log {
        level ERROR
    }
}

{$DOMAIN} {
    rate_limit {
        zone myzone {
            key {remote_ip}
            events 20
            window 1m
        }
    }

    handle {
        reverse_proxy {
            # THIS WORKS
            # to node-server-1:5000 node-server-2:5000


            # THIS DOESN'T WORK
                to {$UPSTREAMS}


            # https://caddyserver.com/docs/caddyfile/directives/reverse_proxy#load-balancing
            lb_policy round_robin

            lb_try_duration 1s
        }
    }

    # https://caddyserver.com/docs/caddyfile/directives/handle_errors#examples
    handle_errors 429 {
        respond "You're being rate limited. Please try again in 1 minute."
    }
}

Answer 1

提示位于您链接的 Caddy 文档中...

这种形式的环境变量在 Caddyfile 解析开始之前被替换

您需要将它们设置为 Dockerfile 或构建参数中的

ENV

 条目。

但是...

如果您想将环境变量的替换

推迟到运行时，您可以使用 标准 {env.*} 占位符

尝试用这个代替

to {env.UPSTREAMS}