From 01b3a6a23476d2b34a67e418cd5b0977166f9541 Mon Sep 17 00:00:00 2001
From: Robert Goldmann <deadlocker@gmx.de>
Date: Sun, 31 Oct 2021 00:32:51 +0200
Subject: [PATCH] #9 - documented cleanup
---
README.md | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/README.md b/README.md
index 1396c2f..babf42b 100644
--- a/README.md
+++ b/README.md
@@ -7,6 +7,43 @@ An interactive OpenAPI Swagger documentation can be accessed by opening the serv
- temperature
- humidity
+## Automatic database cleanup
+Collecting data from many sensors in short time intervals will eventually lead to an increased database size.
+The total number of measurements and the size on disk can be retrieved via the API: GET [http://localhost:10003/database/databaseInfo](http://localhost:10003/database/databaseInfo)
+
+StorageLeaf provides an automatic cleanup procedure that deletes old measurements based on retention policies.``
+
+### Settings
+All cleanup settings are specified in the database section in `settings.json`.
+```json
+"cleanup": {
+ "forceBackupAfterCleanup": false,
+ "retentionPolicies": [
+ {
+ "numberOfMeasurementsPerDay": 24,
+ "ageInDays": 30
+ }
+ ],
+ "retentionPolicies": {
+ "enable": true,
+ "cronSchedule": "* * * * *"
+ }
+}
+```
+
+- `forceBackupAfterCleanup` - If true, a backup is enforced after cleanup (instead of waiting for configured number of modifications).
+- `automatic` - The cleanup process can run automatically.
+ - `enable` - Enables the scheduling of automatic cleanup.
+ - `cronSchedule` - Specifies the schedule for the automatic cleanup in cron syntax. (Note: If a cleanup is still running when the next cron trigger fires, the running cleanup is not aborted and the trigger discarded.)
+- `retentionPolicies` - Specifies how the measurements are cleaned.
+ - `ageInDays` - All measurements older than this number of days will be affected by this retention policy.
+ - `numberOfMeasurementsPerDay` - While running the cleanup process all measurements are grouped by date. Each retention policy specifies how many measurements are kept at most for every day. To determine which measurements should be kept, the date is divided into equally spaced time points. For every time point the closest measurement will be kept.
+
+
+**Note:** The initial cleanup of an existing database can take a considerable amount of time to complete!
+
+The cleanup can also be triggered manually via API: POST [http://localhost:10003/database/databaseCleanup](http://localhost:10003/database/databaseCleanup)
+The status is available via GET [http://localhost:10003/database/databaseCleanup](http://localhost:10003/database/databaseCleanup)
## Credits
--
GitLab