Strapi 3 custom middleware for partial content

config-environments-development-middleware.json

{
  "partial": {
    "enabled": true
   }
}

config-middleware.json

{
  "timeout": 100,
  "load": {
    "before": [
      "responseTime",
      "logger",
      "cors",
      "responses",
      "gzip"
    ],
    "order": [
      "partial", "public"
    ],
    "after": [
      "parser",
      "router"
    ]
  }
}

middlewares-partial-index.js

const koaPart = require('koa-partial-content');
const path = require('path');
const basePath = __dirname + '../../../public';
const part = new koaPart(basePath);

module.exports = strapi => {
  return {
    // can also be async
    initialize() {
      strapi.app.use(async (ctx, next) => {
        const absolutePath = path.join(basePath, ctx.path);
        if (!part.isMedia(absolutePath)) {
          return next();
        }
        try {
          await part.sendResponse(ctx);
        } catch (e) {
          console.log(e);
          return await next();
        }
      });
    },
  };
};