MinIO server allows selectively specify WORM for specific objects or configuring a bucket with default object lock configuration that applies default retention mode and retention duration to all incoming objects. Essentially, this makes objects in the bucket immutable i.e. delete and overwrite are not allowed till stipulated time specified in the bucket's object lock configuration or object retention.
Object locking requires locking to be enabled on a bucket at the time of bucket creation. In addition, a default retention period and retention mode can be configured on a bucket to be
WORM on a bucket is enabled by setting object lock configuration. This configuration is applied to existing and new objects in the bucket. Below is an example sets `Governance` mode and one day retention time from object creation time of all objects in `mybucket`.
PutObject API allows setting per object retention mode and retention duration using `x-amz-object-lock-mode` and `x-amz-object-lock-retain-until-date` headers. This takes precedence over any bucket object lock configuration w.r.t retention.
- When global WORM is enabled by `MINIO_WORM` environment variable or `worm` field in configuration file supersedes bucket level WORM and `PUT object lock configuration` REST API is disabled.
- global WORM and objects in `Compliance` mode can never be overwritten
- Currently `Governance` mode does not allow overwriting an existing object as versioning is not
available in MinIO. To that extent `Governance` mode is similar to `Compliance`. However,
if user has requisite `Governance` bypass permissions, an object in `Governance` mode can be overwritten.
- Once object lock configuration is set to a bucket, new objects inherit the retention settings of the bucket object lock configuration (if set) or the retention headers set in the PUT request
