[![Deploy to now](https://deploy.now.sh/static/button.svg)](https://deploy.now.sh/?repo=https://github.com/zeit/next.js/tree/master/examples/with-strict-csp) # Strict CSP example ## How to use ### Using `create-next-app` Execute [`create-next-app`](https://github.com/segmentio/create-next-app) with [Yarn](https://yarnpkg.com/lang/en/docs/cli/create/) or [npx](https://github.com/zkat/npx#readme) to bootstrap the example: ```bash npx create-next-app --example with-strict-csp with-strict-csp-app # or yarn create next-app --example with-strict-csp with-strict-csp-app ``` ### Download manually Download the example: ```bash curl https://codeload.github.com/zeit/next.js/tar.gz/canary | tar -xz --strip=2 next.js-canary/examples/with-strict-csp cd with-strict-csp ``` Install it and run: ```bash npm install npm run dev # or yarn yarn dev ``` Deploy it to the cloud with [now](https://zeit.co/now) ([download](https://zeit.co/download)) ```bash now ``` ## The idea behind the example If you want to implement a CSP, the most effective way is to follow the [strict CSP](https://csp.withgoogle.com/docs/strict-csp.html) approach. For it to work, we need to generate a nonce on every request. This example uses [Helmet](https://github.com/helmetjs/helmet) to configure the CSP and add the appropriate headers to all server responses. The nonce is generated with [uuid](https://github.com/kelektiv/node-uuid). Then we can pass the nonce to `` and `` in the custom ``.