Question

在nginx的docker构建过程中，我将REST API的端点作为env变量传递，并花了6个小时尝试了大多数建议，我已经没有足够的东西/耐心尝试了。

我要替换的

nginx conf：

location /my-api/ {
    proxy_pass  ${api_url}/;
}

我正在docker构建期间传递此值：

#base_url comes from system env 
docker build --build-arg base_api_url=$base_url

我在Dockerfile中得到了这个值：

ARG base_api_url
ENV  api_url=$base_api_url

# This prints the value
RUN echo "api_url= ${api_url}" . 

COPY package.json /usr/src/app/package.json
RUN npm install
COPY . /usr/src/app
RUN npm run build

FROM nginx:1.15.8-alpine
COPY --from=builder /usr/src/app/build /usr/share/nginx/html
EXPOSE 80

# this works
COPY nginx.conf /etc/nginx/nginx.conf.template

# Initially following code was building and deploying docker image and url was hard coded. it was working
# COPY nginx.conf /etc/nginx/conf.d/default.conf 
# Below will start the image but no REST endpoint configured
# CMD ["nginx", "-g", "daemon off;"]

# To substitute the api url few of the many things I have tried.
# Non of the below, have been able to replace the env api_url with its value 
# Actually I don't know -- since /etc/nginx/conf.d/default.conf is not replaced at all

# CMD /bin/bash -c "envsubst < nginx.conf > /etc/nginx/conf.d/default.conf && exec nginx -g 'daemon off;'"
# CMD /bin/sh -c "envsubst < nginx.conf > /etc/nginx/conf.d/default.conf && nginx -g 'daemon off;' || cat /etc/nginx/nginx.conf"

# Last status
CMD envsubst < /etc/nginx/nginx.conf.template > /etc/nginx/conf.d/default.conf && exec nginx -g 'daemon off;'

/etc/nginx/conf.d/default.conf应该替换为api_url：

location /my-api/ {
    proxy_pass http://theApiURL;
}

我也尝试过专门传递环境变量，例如：

CMD envsubst ${api_url} < /etc/nginx/nginx.conf.template > /etc/nginx/conf.d/default.conf && exec nginx -g 'daemon off;'

以及使用tee之类的变体。

感谢任何帮助/指导来解决此问题。

Answer 1

我通常在sed的部署脚本中，在Dockerfile之外执行此操作。

这是一个例子：

 #!/usr/bin/env bash
 # Deploys locally for dev work

 set -e
 export API_URL=www.theapiurl.com

 sed "s/api_url/${API_URL}/" nginx.conf.template > nginx.conf
 ...

 # run docker
 docker-compose build --no-cache
 docker-compose up -d

您当然可以设置环境变量，但是对于您的用例来说很有意义。我发现这种方法比Docker提供的任何方法都要灵活得多。

无法替换Dockerfile中的Nginx环境变量

1 个答案: