The project is configured to upload over a serial connection by default. You can change this to use OTA updates by uncommenting the relevant lines in ['platformio.ini'](platformio.ini).
The interface has been configured with create-react-app and react-app-rewired so the build can customized for the target device. The large artefacts are gzipped and source maps and service worker are excluded from the production build. This reduces the production build to around ~200k, which easily fits on the device.
Change to the ['interface'](interface) directory with your bash shell (or Git Bash) and use the standard commands you would with any react app built with create-react-app:
> **Note**: The build command will also delete the previously built interface, in the ['data/www'](data/www) directory, replacing it with the freshly built one ready to upload to the device.
You can run a local development server to allow you preview changes to the front end without the need to upload a file system image to the device after each change. Change to the interface directory and run the following command:
The endpoint root path can be found in ['interface/.env.development'](interface/.env.development), defined as the environment variable 'REACT_APP_ENDPOINT_ROOT'. This needs to be the root URL of the device running the back end, for example:
You can enable CORS on the back end by uncommenting the -D ENABLE_CORS build flag in ['platformio.ini'](platformio.ini) then re-building and uploading the firmware to the device. The default settings assume you will be accessing the development server on the default port on [http://localhost:3000](http://localhost:3000) this can also be changed if required:
```
-D ENABLE_CORS
-D CORS_ORIGIN=\"http://localhost:3000\"
```
## Device Configuration
As well as containing the interface, the SPIFFS image (in the ['data'](data) folder) contains a JSON settings file for each of the configurable features. The config files can be found in the ['data/config'](data/config) directory:
File | Description
---- | -----------
[apSettings.json](data/config/apSettings.json) | Access point settings
It is recommended that you change the JWT secret and user credentials from their defaults protect your device. You can do this in the user interface, or by modifying [securitySettings.json](data/config/securitySettings.json) before uploading the file system image.
This project supports ESP8266 and ESP32 platforms. To support OTA programming, enough free space to upload the new sketch and file system image will be required. It is recommended that a board with at least 2mb of flash is used.
By default, the target device is "esp12e". This is a common ESP8266 variant with 4mb of flash:
![ESP12E](/media/esp12e.jpg?raw=true "ESP12E")
The settings file ['platformio.ini'](platformio.ini) configures the platform and board:
```
[env:esp12e]
platform = espressif8266
board = esp12e
```
If you want to build for an ESP32 device, all you need to do is re-configure ['platformio.ini'](platformio.ini) with your devices settings.
![ESP32](/media/esp32.jpg?raw=true "ESP32")
Building for the common esp32 "node32s" board for example requires the following configuration:
The app can be easily themed by editing the [MaterialUI theme](https://material-ui.com/customization/themes/). Edit the theme in ['interface/src/App.js'](interface/src/App.js) as you desire:
You can replace the app icon is located at ['interface/public/app/icon.png'](interface/public/app/icon.png) with one of your preference. A 256 x 256 PNG is recommended for best compatibility.
The app name displayed on the login page and on the menu bar can be modified by editing the REACT_APP_NAME property in ['interface/.env'](interface/.env)
There is also a manifest file which contains the app name to use when adding the app to a mobile device, so you may wish to also edit ['interface/public/app/manifest.json'](interface/public/app/manifest.json):
The back end is a set of REST endpoints hosted by a [ESPAsyncWebServer](https://github.com/me-no-dev/ESPAsyncWebServer) instance. The ['lib/framework'](lib/framework) directory contains the majority of the back end code. The framework contains of a number of useful utility classes which you can use when extending it. The project also comes with a demo project to give you some help getting started.
The framework's source is split up by feature, for example [WiFiScanner.h](lib/framework/WiFiScanner.h) implements the end points for scanning for available networks where as [WiFiSettingsService.h](lib/framework/WiFiSettingsService.h) handles configuring the WiFi settings and managing the WiFi connection.
The ['src/main.cpp'](src/main.cpp) file constructs the webserver and initializes the framework. You can add endpoints to the server here to support your IoT project. The main loop is also accessable so you can run your own code easily.
The following code creates the web server, esp8266React framework and the demo project instance:
Now in the `setup()` function the initialization is performed:
```cpp
void setup() {
// start serial and filesystem
Serial.begin(SERIAL_BAUD_RATE);
SPIFFS.begin();
// set up the framework
framework.init(&server);
// begin the demo project
demoProject.init(&server);
// start the server
server.begin();
}
```
Finally the loop calls the framework's loop function to service the frameworks features. You can add your own code in here, as shown with the demo project:
```cpp
void loop() {
// run the framework's loop function
framework.loop();
// run the demo project's loop function
demoProject.loop();
}
```
### Adding endpoints
There are some simple classes that support adding configurable services/features to the device:
Class | Description
----- | -----------
[SimpleService.h](lib/framework/SimpleService.h) | Exposes an endpoint to read and write settings as JSON. Extend this class and implement the functions which serialize the settings to/from JSON.
[SettingsService.h](lib/framework/SettingsService.h) | As above, however this class also handles persisting the settings as JSON to the file system.
[AdminSettingsService.h](lib/framework/AdminSettingsService.h) | Extends SettingsService to secure the endpoint to administrators only, the authentication predicate can be overridden if required.
The demo project shows how these can be used, explore the framework classes for more examples.
### Security features
The framework has security features to prevent unauthorized use of the device. This is driven by [SecurityManager.h](lib/framework/SecurityManager.h).
On successful authentication, the /rest/signIn endpoint issues a JWT which is then sent using Bearer Authentication. The framework come with built in predicates for verifying a users access level. The built in AuthenticationPredicates can be found in [SecurityManager.h](lib/framework/SecurityManager.h):
Predicate | Description
-------------------- | -----------
NONE_REQUIRED | No authentication is required.
IS_AUTHENTICATED | Any authentication is permitted.
IS_AUTHENTICATED | Any authentication is permitted.
You can use the security manager to wrap any web handler with an authentication predicate:
Alternatively you can extend [AdminSettingsService.h](lib/framework/AdminSettingsService.h) and optionally override `getAuthenticationPredicate()` to secure an endpoint.
There will now be a REST service exposed on "/exampleSettings" for reading and writing (GET/POST) the settings. Any modifications will be persisted in SPIFFS, in this case to "/config/exampleSettings.json"
Sometimes you need to perform an action when the settings are updated, you can achieve this by overriding the onConfigUpdated() function which gets called every time the settings are updated. You can also perform an action when the service starts by overriding the begin() function, being sure to call SettingsService::begin():