Redwood Cookbook - Getting OG and meta tags working with nginx, pre-render.io and docker

Dockerfile

# Multi-stage
# 1) Node image for building frontend assets
# 2) nginx stage to serve frontend assets
# Name the node stage "builder"

# Set your env variables here. 
FROM node:15 AS builder
ARG FIREBASE_API_KEY
ARG FIREBASE_PROJECT_ID
ENV FIREBASE_API_KEY=$FIREBASE_API_KEY
ENV FIREBASE_PROJECT_ID=$FIREBASE_PROJECT_ID

# Set working directory
WORKDIR /app
# Copy all files from current directory to working dir in image
COPY . .
# install node modules and build assets
RUN env
RUN yarn
ARG NODE_ENV
ENV NODE_ENV=$NODE_ENV
RUN yarn rw build web
# nginx state for serving content
FROM nginx:alpine
# Set working directory to nginx asset directory
WORKDIR /usr/share/nginx/html
# Remove default nginx static assets
RUN rm -rf ./*
# Copy static assets from builder stage
COPY nginx.conf /etc/nginx/conf.d/default.conf
COPY --from=builder /app/web/dist .
# Containers run nginx with global directives and daemon off
ENTRYPOINT ["nginx", "-g", "daemon off;"]

nginx.conf

server {
    listen 80;
    listen   [::]:80 default ipv6only=on;
    server_name _; # all hostnames

    root /usr/share/nginx/html;
    index  index.html;

    location / {
        try_files $uri @prerender;
    }

    location @prerender {
        proxy_set_header X-Prerender-Token YOUR_TOKEN_HERE;

        set $prerender 0;
        if ($http_user_agent ~* "googlebot|bingbot|yandex|baiduspider|twitterbot|facebookexternalhit|rogerbot|linkedinbot|embedly|quora link preview|showyoubot|outbrain|pinterest\/0\.|pinterestbot|slackbot|vkShare|W3C_Validator|whatsapp") {
            set $prerender 1;
        }
        if ($args ~ "_escaped_fragment_") {
            set $prerender 1;
        }
        if ($http_user_agent ~ "Prerender") {
            set $prerender 0;
        }
        if ($uri ~* "\.(js|css|xml|less|png|jpg|jpeg|gif|pdf|doc|txt|ico|rss|zip|mp3|rar|exe|wmv|doc|avi|ppt|mpg|mpeg|tif|wav|mov|psd|ai|xls|mp4|m4a|swf|dat|dmg|iso|flv|m4v|torrent|ttf|woff|svg|eot)") {
            set $prerender 0;
        }

        #resolve using Google's DNS server to force DNS resolution and prevent caching of IPs
        resolver 8.8.8.8;

        if ($prerender = 1) {

            #setting prerender as a variable forces DNS resolution since nginx caches IPs and doesnt play well with load balancing
            set $prerender "service.prerender.io";
            rewrite .* /https://$host$request_uri? break;
            proxy_pass http://$prerender;
        }
        if ($prerender = 0) {
            rewrite .* /index.html break;
        }
    }
}