docker: allow to control import/export rate limiting parameters

The newly introduces environment variables are IMPORT_EXPORT_RATE_LIMIT_WINDOW
and IMPORT_EXPORT_MAX_REQ_PER_IP.

doc/docker.md

@@ -73,6 +73,8 @@ Available options:
 * `USER_PASSWORD`: the password for the first user `user` (leave unspecified if you do not want to create it)
 * `TRUST_PROXY`: set to `true` if you are using a reverse proxy in front of Etherpad (for example: Traefik for SSL termination via Let's Encrypt). This will affect security and correctness of the logs if not done
 * `IMPORT_MAX_FILE_SIZE`: maximum allowed file size when importing a pad, in bytes. Default: 52428800 (50 MB)
+* `IMPORT_EXPORT_MAX_REQ_PER_IP`: maximum number of import/export calls per IP. Default: 10
+* `IMPORT_EXPORT_RATE_LIMIT_WINDOW`: the call rate for import/export requests will be estimated in this time window (in milliseconds). Default: 90000 ms
 * `LOGLEVEL`: valid values are `DEBUG`, `INFO`, `WARN` and `ERROR`
 
 ### Examples

settings.json.docker

@@ -415,10 +415,10 @@
  */
  "importExportRateLimiting": {
  // duration of the rate limit window (milliseconds)
- "windowMs": 90000,
+ "windowMs": "${IMPORT_EXPORT_RATE_LIMIT_WINDOW:90000}",
 
  // maximum number of requests per IP to allow during the rate limit window
- "max": 10
+ "max": "${IMPORT_EXPORT_MAX_REQ_PER_IP:10}"
  },
 
  /*