How can I use environment variables passed from deployment file in nginx.conf-CodePudding

Below is the logic in my docker file. I am using nginx to build the application.

FROM node:14-alpine as builder

COPY package.json ./
RUN npm install && mkdir /app && mv ./node_modules ./app
WORKDIR /app

COPY . .

RUN npm run build


FROM nginx:1.16.0-alpine
COPY --from=builder /app/build /usr/share/nginx/html
RUN rm /etc/nginx/conf.d/default.conf
COPY nginx.conf /etc/nginx/conf.d

EXPOSE 3000

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

Below is the nginx.conf file

server {
   listen 3000;
      
   location / {
     root /usr/share/nginx/html;
     index index.html index.htm;
     try_files $uri $uri/ /index.html =404;
   }
  
   location /api {
    #  rewrite /api/api(.*) /$1 break;
     proxy_pass http://${backend_host}:${backend_port}/api;
   }
      
   include /etc/nginx/extra-conf.d/*.conf;
}

backend_host and backend_port in the proxy_pass URL will be provided while deploying the image using Deployment file.

Is this possible? If not is there any alternative way for this?

CodePudding user response：

If you want to dynamically mount the nginx.conf I would suggest using the config map with your deployment.yaml

So this way you re-use your docker image multiple times without recreating it and pass the config map to update it.

You docker file will be

FROM node:14-alpine as builder
COPY package.json ./
RUN npm install && mkdir /app && mv ./node_modules ./app
WORKDIR /app
COPY . .
RUN npm run build


FROM nginx:1.16.0-alpine
COPY --from=builder /app/build /usr/share/nginx/html
RUN rm /etc/nginx/conf.d/default.conf
EXPOSE 3000
CMD ["nginx", "-g", "daemon off;"]

Example configmap

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-config
data:
  default.conf: |-
    server {
            listen 80 default_server;
            root /var/www/html;
            server_name  _;
            index index.php;
            location / {
                try_files $uri $uri/ /index.php?$args;
            }
            location ~ \.php$ {
                fastcgi_split_path_info ^(. \.php)(/. )$;
                fastcgi_pass 127.0.0.1:9000;
                fastcgi_index index.php;
                include fastcgi_params;
                fastcgi_param   PATH_INFO       $fastcgi_path_info;
                fastcgi_param   SCRIPT_FILENAME $document_root$fastcgi_script_name;
            }
        }

Mount the config map to deployment

apiVersion: apps/v1
kind: Deployment
metadata:
  name: app
  labels:
    app: app
spec:
  selector:
    matchLabels:
      app: app
  replicas: 1
  template:
    metadata:
      labels:
        app: app
    spec:
      containers:
        - name: app
          image: app-image
          ports:
          - containerPort: 80
          volumeMounts:
            - name: nginx-config
              mountPath: /etc/nginx/nginx.conf
              subPath: nginx.conf
      volumes:
        - name: nginx-config
          configMap:
            name: confnginx

For more details read at : https://blog.meain.io/2020/dynamic-reverse-proxy-kubernetes/