Merge pull request #12 from os2display/feature/screen-status

Added screen status documentation

Author: tuj

content_structure/screen-status.md

@@ -0,0 +1,86 @@
+---
+layout: default
+title: Screen status
+parent: Content Structure
+nav_order: 8
+---
+
+# Screen status
+
+## Preamble
+
+Screen status consists of 2 elements. Tracking latest request from a screen client.
+This data is collected and exposed through the API.
+
+The other part is in the admin where the data can be exposed to the user.
+
+## Setup
+
+### API
+
+Enable tracking latest requests from the screen clients in the API by setting the following values in `.env.local`:
+
+```dotenv
+TRACK_SCREEN_INFO=true
+# Data will only be updated with this interval:
+TRACK_SCREEN_INFO_UPDATE_INTERVAL_SECONDS=300
+```
+
+In the infrastructure files these variables can be set by the environment variables:
+
+```dotenv
+APP_TRACK_SCREEN_INFO=true
+APP_TRACK_SCREEN_INFO_UPDATE_INTERVAL_SECONDS=300
+```
+
+### Admin
+
+Set the following value in public/config.json to enable showing screen status information in the Admin.
+
+```json
+{
+  "showScreenStatus": true
+}
+```
+
+In the infrastructure files this variable can be set by the environment variable:
+
+```dotenv
+APP_SHOW_SCREEN_STATUS=true
+```
+
+##  List view
+
+In the list view of screens, there is a column called "Status".
+
+This column shows the status of the connection of a "screen" in the administration and an
+actual "machine" running the screen data. 
+
+This status can be:
+
+* "+ Tilkobl": The screen is not connected to a machine.
+* ✓ (green):  The machine is connected and running the latest code.
+* i (yellow circle): The machine is not running the newest released code.
+* ! (red triangle): The machine has not called the API within the last hour or the access token is expired.
+
+## Screen edit view
+
+In the screen edit view, the "Tilkobling" section shows the status of the connection between the
+screen entity and a machine running the screen data.
+
+The status can be:
+
+* "Skærmen er tilkoblet" (green): The machine is connected and running the latest code.
+* "Skærmen kører ikke seneste udgivelse" (yellow circle): The machine is not running the newest released code.
+* "Skærmen har ikke kommunikeret i mere end en time" (red triangle): The machine has not called the API the latest hour.
+
+Furthermore, the section "Tilkobling" will show the following data:
+
+```text
+* Seneste kommunikation: 14/12 2024 11:35
+* Version: 1.0.9
+* Kodeudgivelsestidspunkt: 17/6 2024 17:26
+```
+
+This shows when the latest communication has occured, what client version the machine is running,
+and the time of client code release.