ESP Web Tools

ESP Web Tools is a set of open source tools to allow working with ESP devices in the browser. The code is available on GitHub.

To try it out and install the ESPHome firmware, connect an ESP to your computer and hit the button:

Note, this only works in desktop Chrome and Edge. Android support should be possible but has not been implemented yet.

This works by combining Web Serial with a manifest which describes the firmware. It will automatically detect the type of the connected ESP device and find the right firmware files in the manifest.

Using ESP Web Tools on your website

To add this to your own website, create a manifest and add the button to your website. Make sure you update the manifest attribute to point at your manifest.

<script
  type="module"
  src="https://unpkg.com/esp-web-tools@1.0.3/dist/web/install-button.js?module"
></script>

<esp-web-install-button
  manifest="firmware_build/manifest.json"
></esp-web-install-button>

Your website needs to be served over https://. If your manifest is hosted on another server, make sure you configure the CORS-headers for your manifest and firmware files such that your website is allowed to fetch those files by adding the header Access-Control-Allow-Origin: https://domain-of-your-website.com.

Add the attribute erase-first if you want to first fully erase the ESP prior to installation.

ESP Web Tools can also be integrated in your projects by installing it via NPM:
npm install --save esp-web-tools

Creating your manifest

ESP Web Tools manifest describe the firmware that you want to install. It allows specifying different builds for the different types of ESP devices. Current supported devices are ESP8266, ESP32 and ESP32-S2. The correct build will be automatically selected based on the type of the ESP device we detect via the serial port.

{
  "name": "ESPHome",
  "builds": [
    {
      "chipFamily": "ESP32",
      "improv": true,
      "parts": [
        { "path": "bootloader.bin", "offset": 4096 },
        { "path": "partitions.bin", "offset": 32768 },
        { "path": "ota.bin", "offset": 57344 },
        { "path": "firmware.bin", "offset": 65536 }
      ]
    },
    {
      "chipFamily": "ESP8266",
      "parts": [
        { "path": "esp8266.bin", "offset": 0 }
      ]
    }
  ]
}

Each build contains a list of parts to be flashed to the ESP device. Each part consists of a path to the file and an offset on the flash where it should be installed. Part paths are resolved relative to the path of the manifest, but can also be URLs to other hosts.

Each build also allows you to specify if it supports the Improv WiFi standard. If it does, the user will be offered to configure the WiFi after flashing is done.

Customizing the look and feel

You can customize both the activation button and the message that is shown when the user uses an unsupported browser. This can be done using the activate and unsupported slots:

<esp-web-install-button
  manifest="firmware_build/manifest.json"
  erase-first
>
  <button slot="activate">Custom install button</button>
  <span slot="unsupported">Ah snap, your browser doesn't work!</span>
</esp-web-install-button>