Object Lifecycle Management

Object lifecycle management allows you to define rules that automatically transition objects between storage classes or delete them based on conditions like age, storage class, or version status. This is essential for cost optimisation and data governance — ensuring that data moves to cheaper storage as it ages and is deleted when no longer needed.

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How Lifecycle Rules Work

Lifecycle rules are configured at the bucket level. Each rule consists of:

1. Conditions — when the rule should apply (e.g., age > 90 days)
2. Action — what to do (SetStorageClass or Delete)

Cloud Storage evaluates lifecycle rules once per day (asynchronously). Changes are not instantaneous — there may be a delay of up to 24 hours.

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Actions

SetStorageClass

Transitions an object to a different (colder) storage class:

{
  "lifecycle": {
    "rule": [
      {
        "action": { "type": "SetStorageClass", "storageClass": "NEARLINE" },
        "condition": { "age": 30 }
      },
      {
        "action": { "type": "SetStorageClass", "storageClass": "COLDLINE" },
        "condition": { "age": 90 }
      },
      {
        "action": { "type": "SetStorageClass", "storageClass": "ARCHIVE" },
        "condition": { "age": 365 }
      }
    ]
  }
}

Note: You can only transition to a colder class (Standard to Nearline to Coldline to Archive). To move to a warmer class, you must manually rewrite the object or use Autoclass.

Delete

Permanently removes the object:

{
  "action": { "type": "Delete" },
  "condition": { "age": 730 }
}

AbortIncompleteMultipartUpload

Cleans up incomplete multipart uploads:

{
  "action": { "type": "AbortIncompleteMultipartUpload" },
  "condition": { "age": 7 }
}

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Conditions

Condition	Description
age	Number of days since the object was created
createdBefore	Object was created before this date
isLive	true for live (current) versions; false for non-current versions
numNewerVersions	Number of newer versions that exist (for versioned buckets)
matchesStorageClass	Object is currently in the specified class(es)
matchesPrefix	Object name starts with the specified string
matchesSuffix	Object name ends with the specified string
daysSinceNoncurrentTime	Days since the object became non-current
daysSinceCustomTime	Days since a custom time was set on the object

You can combine multiple conditions in a single rule — all conditions must be true for the action to trigger (AND logic).

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Configuring Lifecycle Rules

Using gsutil