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.
The interface will be automatically built by PlatformIO before it builds the firmware. The project can be configured to serve the interface from either SPIFFS or PROGMEM as your project requires. The default configuration is to serve the content from SPIFFS which requires an additional upload step which is documented below.
If service content from SPIFFS (default), build the project first. Then the compiled interface may be uploaded to the device by pressing the "Upload File System image" button:
You can configure the project to serve the interface from PROGMEM by uncommenting the -D PROGMEM_WWW build flag in ['platformio.ini'](platformio.ini) then re-building and uploading the firmware to the device.
Be aware that this will consume ~150k of program space which can be especially problematic if you already have a large build artefact or if you have added large javascript dependencies to the interface. The ESP32 binaries are large already, so this will be a problem if you are using one of these devices and require this type of setup.
A method for working around this issue can be to reduce the amount of space allocated to SPIFFS by configuring the device to use a differnt strategy partitioning. If you don't require SPIFFS other than for storing config one approach might be to configure a minimal SPIFFS partition.
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'](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:
```bash
cd interface
```
Install the npm dependencies, if required and start the development server:
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:
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.
The settings file ['platformio.ini'](platformio.ini) configures the supported environments. Modify these, or add new environments for the devides you need to support. The default environments are as follows:
If you want to build for a different device, all you need to do is re-configure ['platformio.ini'](platformio.ini) and select an alternative environment by modifying the default_envs variable. Building for the common esp32 "node32s" board for example:
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:
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:
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):
Alternatively you can extend [AdminSettingsService.h](lib/framework/AdminSettingsService.h) and optionally override `getAuthenticationPredicate()` to secure an endpoint.
It is recommend that you explore the framework code to gain a better understanding of how to use it's features. The framework provides APIs so you can add your own services or features or, if required, directly configure or observe changes to core framework features. Some of these capabilities are detailed below.
### Adding a service with persistant settings
The following code demonstrates how you might extend the framework with a feature which requires a username and password to be configured to drive an unspecified feature.
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(). You can also provide a "loop" function in order to allow your service class continuously perform an action, calling this from the main loop.
getSecurityManager() | The security manager - detailed above
getSecuritySettingsService() | Configures the users and other security settings
getWiFiSettingsService() | Configures and manages the WiFi network connection
getAPSettingsService() | Configures and manages the Access Point
getNTPSettingsService() | Configures and manages the network time
getOTASettingsService() | Configures and manages the Over-The-Air update feature
These can be used to observe changes to settings. They can also be used to fetch or update settings directly via objects, JSON strings and JsonObjects. Here are some examples of how you may use this.