✅JSON Patch Test Operation
Verify values before applying changes
What is the Test Operation?
The test operation checks if the value at the specified path matches the expected value. If the test fails, evaluation stops at that operation. This enables conditional patching and optimistic concurrency control.
Syntax
Examples
Test Before Update
Verify a value before replacing it
Patch:
Before:
After:
Test Object Match
Verify an entire object matches
Patch:
Before:
After:
Conditional Delete
Only remove if value matches
Patch:
Before:
After:
Real World: Optimistic Concurrency Check
Update only if nobody else touched the record
Patch:
Before:
After:
Common Use Cases
- Optimistic concurrency control
- Conditional updates based on current state
- Preventing race conditions
- Validating assumptions before changes
Best Practices
- Place test operations before related modifications
- Use for version checking and conflict detection
- Deep equality comparison for objects and arrays
- Essential for safe concurrent updates
Test Operation FAQ
What happens when a test operation fails?
Patch evaluation stops at the failed test. RFC 6902 does not require rollback of earlier operations, so place tests before the writes they guard and verify your implementation.
Is the number 1 equal to 1.0 in a test?
RFC 6902 compares numbers mathematically, so 1 and 1.0 match. But 1 and "1" do not: a number never equals a string, and that type mismatch is the most common test failure.
Where should test operations go in a patch?
Before the operations they guard. Operations run in order, so a test only protects changes that come after it.
Try the Test Operation Now
Use our free online JSON Patch generator to create test patches instantly
🚀 Open JSON Patch Generator