Object versioning in GCP - Step-by-Step Execution

Process Flow - Object versioning

Enable Versioning on Bucket

↓

Upload Object (v1)

↓

Upload Object (v2)

↓

List Object Versions

↓

Access Specific Version

↓

Delete Specific Version or All Versions

This flow shows enabling versioning on a storage bucket, uploading multiple versions of an object, listing versions, accessing specific versions, and deleting versions.

Execution Sample

GCP

gsutil versioning set on gs://my-bucket
 gsutil cp file.txt gs://my-bucket/file.txt
 gsutil cp file_v2.txt gs://my-bucket/file.txt
 gsutil ls -a gs://my-bucket/file.txt

Enable versioning on a bucket, upload two versions of the same file, then list all versions.

Process Table

Step	Action	Bucket Versioning State	Object Name	Version ID	Result
1	Enable versioning on bucket	Enabled	-	-	Bucket versioning enabled
2	Upload file.txt as file.txt	Enabled	file.txt	v1	Object uploaded as version v1
3	Upload file_v2.txt as file.txt	Enabled	file.txt	v2	New version v2 created, old version v1 retained
4	List all versions of file.txt	Enabled	file.txt	v1, v2	Both versions listed
5	Access version v1	Enabled	file.txt	v1	Version v1 content retrieved
6	Delete version v2	Enabled	file.txt	v2	Version v2 deleted, version v1 remains
7	Delete version v1	Enabled	file.txt	v1	Version v1 deleted, no versions remain
8	List all versions after deletions	Enabled	file.txt	-	No versions found
9	Upload new file.txt	Enabled	file.txt	v3	New version v3 created
10	Disable versioning on bucket	Suspended	-	-	Bucket versioning suspended
11	Upload file.txt again	Suspended	file.txt	-	Object overwritten, no versioning
12	List versions after suspension	Suspended	file.txt	v3	Only version v3 exists, no new versions created
13	End	-	-	-	Process complete

💡 Versioning stops creating new versions after suspension; existing versions remain until deleted.

Status Tracker

Variable	Start	After Step 2	After Step 3	After Step 6	After Step 7	After Step 9	After Step 10	After Step 11
Bucket Versioning State	Suspended	Enabled	Enabled	Enabled	Enabled	Enabled	Suspended	Suspended
file.txt Versions	None	v1	v1, v2	v1	None	v3	v3	v3

Key Moments - 3 Insights

Why do old versions remain after uploading a new version?

Because versioning is enabled (see steps 2 and 3), each upload creates a new version without deleting old ones.

What happens when versioning is suspended and a file is uploaded again?

No new versions are created; the existing object is overwritten (see steps 10 and 11).

How can you access a specific version of an object?

By specifying the version ID when accessing the object, as shown in step 5.

Visual Quiz - 3 Questions

Look at the execution table, what is the bucket versioning state after step 10?

A Suspended

B Enabled

C Disabled

D Unknown

💡 Hint

Check the 'Bucket Versioning State' column at step 10 in the execution table.

At which step are both versions v1 and v2 present?

A Step 2

B Step 3

C Step 6

D Step 7

💡 Hint

Look at the 'file.txt Versions' column in the variable tracker and execution table rows.

If versioning was never enabled, what would happen when uploading file.txt twice?

A Two versions would be created

B An error would occur

C Only the latest file would exist, overwriting the previous

D The file would be duplicated with different names

💡 Hint

Refer to steps 10 and 11 where versioning is suspended and uploads overwrite.

Concept Snapshot

Object Versioning in GCP Storage:
- Enable versioning on a bucket to keep old object versions.
- Each upload creates a new version with a unique ID.
- List versions with 'gsutil ls -a'.
- Access or delete specific versions by ID.
- Suspending versioning stops new versions but keeps old ones.

Full Transcript

Object versioning in Google Cloud Storage lets you keep multiple versions of the same file. First, you enable versioning on a bucket. Then, every time you upload a file with the same name, a new version is created instead of overwriting. You can list all versions and access or delete any specific version. If you suspend versioning, new uploads overwrite the existing file without creating new versions, but old versions remain until deleted. This helps protect against accidental deletion or overwrites by keeping history.

Practice

1. What is the main purpose of enabling Object Versioning in a Google Cloud Storage bucket?

easy

A. To keep multiple versions of an object to recover from accidental deletion or overwrite

B. To increase the storage capacity of the bucket automatically

C. To encrypt objects with a stronger encryption key

D. To restrict access to objects based on user roles

Solution

1. Step 1: Understand Object Versioning concept

   Object Versioning allows storing multiple versions of the same object in a bucket.

2. Step 2: Identify the main benefit

   This helps recover previous versions if an object is deleted or overwritten by mistake.

3. Final Answer:

   To keep multiple versions of an object to recover from accidental deletion or overwrite -> Option A

4. Quick Check:

   Object Versioning = Data recovery [OK]

Hint: Versioning means saving old copies to recover later [OK]

Common Mistakes:

• Confusing versioning with encryption
• Thinking versioning increases storage automatically
• Assuming versioning controls access permissions

2. Which of the following commands correctly enables Object Versioning on a Google Cloud Storage bucket named my-bucket?

easy

A. gsutil versioning set on my-bucket

B. gsutil versioning enable gs://my-bucket

C. gsutil versioning set enabled gs://my-bucket

D. gsutil versioning set on gs://my-bucket

Solution

1. Step 1: Recall gsutil syntax for enabling versioning

   The correct command is gsutil versioning set on gs://bucket-name.

2. Step 2: Match the command to the bucket name

   gsutil versioning set on gs://my-bucket matches the correct syntax and bucket name format.

3. Final Answer:

   gsutil versioning set on gs://my-bucket -> Option D

4. Quick Check:

   Enable versioning = gsutil versioning set on [OK]

Hint: Use 'gsutil versioning set on gs://bucket' to enable [OK]

Common Mistakes:

• Omitting 'gs://' prefix
• Using 'enable' instead of 'set on'
• Adding extra words like 'enabled'

3. Consider a bucket with Object Versioning enabled. If you upload a file named report.txt three times with different content, how many versions of report.txt will exist in the bucket?

medium

A. 3

B. 1

C. 2

D. 4

Solution

1. Step 1: Understand versioning behavior on multiple uploads

   Each upload creates a new version if versioning is enabled.

2. Step 2: Count versions after three uploads

   Uploading three times creates three distinct versions of the same object.

3. Final Answer:

   3 -> Option A

4. Quick Check:

   Uploads = Versions when versioning on [OK]

Hint: Each upload creates a new version if versioning is enabled [OK]

Common Mistakes:

• Assuming only one version exists
• Counting versions as uploads minus one
• Confusing versions with copies

4. You enabled Object Versioning on a bucket but notice that old versions are not visible when listing objects. What is the most likely cause?

medium

A. Old versions are automatically deleted after 24 hours

B. Versioning was not actually enabled on the bucket

C. You used gsutil ls which only shows live versions by default

D. You need to enable versioning on each object separately

Solution

1. Step 1: Understand default listing behavior

   By default, gsutil ls shows only the current live versions, not older ones.

2. Step 2: How to list all versions

   Use gsutil ls -a to see all versions including old ones.

3. Final Answer:

   You used gsutil ls which only shows live versions by default -> Option C

4. Quick Check:

   Default list hides old versions [OK]

Hint: Use 'gsutil ls -a' to see all versions [OK]

Common Mistakes:

• Assuming versioning not enabled without checking
• Believing old versions auto-delete quickly
• Thinking versioning applies per object

5. You want to keep only the latest 5 versions of objects in a bucket with Object Versioning enabled to save storage costs. Which approach should you use?

hard

A. Disable Object Versioning and re-enable it every month

B. Set a lifecycle rule to delete noncurrent versions older than a certain age

C. Manually delete old versions using the Cloud Console every week

D. Rename objects to avoid creating new versions

Solution

1. Step 1: Understand lifecycle management for versioned objects

   Lifecycle rules can automatically delete old versions based on age or count.

2. Step 2: Choose the best automated approach

   Setting a lifecycle rule to delete noncurrent versions older than a set time saves costs without manual work.

3. Final Answer:

   Set a lifecycle rule to delete noncurrent versions older than a certain age -> Option B

4. Quick Check:

   Use lifecycle rules to manage old versions [OK]

Hint: Use lifecycle rules to auto-delete old versions [OK]

Common Mistakes:

• Relying on manual deletion which is error-prone
• Disabling versioning loses all version history
• Renaming objects does not control version count