Package io.confluent.kafka.schemaregistry.type.logical.policy

Class LogicalTypeChecker

java.lang.Object

io.confluent.kafka.schemaregistry.type.logical.policy.LogicalTypeChecker

public final class LogicalTypeChecker
extends Object

Entry point for checking a LogicalType against a downstream consumer's rules.

validate(io.confluent.kafka.schemaregistry.type.logical.policy.LogicalTypeChecker.Mode, io.confluent.kafka.schemaregistry.type.logical.LogicalType) takes one schema and asks whether the consumer can use it at all. compare(io.confluent.kafka.schemaregistry.type.logical.policy.LogicalTypeChecker.Mode, io.confluent.kafka.schemaregistry.type.logical.LogicalType, io.confluent.kafka.schemaregistry.type.logical.LogicalType) takes two and asks whether the change between them is safe. The rules live in ValidityChecker and CompatibilityChecker respectively; read those for the rules, call this for the API.

A caller registering a schema needs both. Neither subsumes the other: a schema whose decimal precision exceeds what the consumer supports is unusable whether or not it changed, so a pairwise check alone lets it through on a first registration and on any later one that leaves the offending column untouched.

 ValidityResult validity = LogicalTypeChecker.validate(mode, update);
 CompatibilityResult compatibility = previous == null
     ? CompatibilityResult.compatible()
     : LogicalTypeChecker.compare(mode, previous, update);
 if (!validity.isValid() || !compatibility.isCompatible()) {
   // reject, reporting validity.describe() and compatibility.describe()
 }
 

Both results collect every finding rather than stopping at the first.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	LogicalTypeChecker.Mode	The downstream consumer whose rules should be applied.

Method Summary

Modifier and Type	Method	Description
static CompatibilityResult	compare(LogicalTypeChecker.Mode mode, LogicalType original, LogicalType update)	Whether update may replace original under mode.
static ValidityResult	validate(LogicalTypeChecker.Mode mode, LogicalType type)	Whether type can be used by mode's consumer at all.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

compare

public static CompatibilityResult compare(LogicalTypeChecker.Mode mode,
 LogicalType original,
 LogicalType update)

Whether update may replace original under mode.

Direction is BACKWARD: the update schema must be able to read data written with the original schema. Says nothing about whether either schema is usable on its own terms — pair that with validate(io.confluent.kafka.schemaregistry.type.logical.policy.LogicalTypeChecker.Mode, io.confluent.kafka.schemaregistry.type.logical.LogicalType).

Parameters:

mode - which consumer's rules to apply

original - the currently registered schema

update - the proposed schema

Returns:

every violation found, or CompatibilityResult.compatible() if there are none

validate

public static ValidityResult validate(LogicalTypeChecker.Mode mode,
 LogicalType type)

Whether type can be used by mode's consumer at all.

Independent of any previous version, so this is the only one of the two checks that can reject a subject's first registration.

Parameters:

mode - which consumer's rules to apply

type - the schema to validate

Returns:

every violation found, or ValidityResult.valid() if there are none