org.apache.hudi.avro

Class AvroSchemaCompatibility

java.lang.Object

org.apache.hudi.avro.AvroSchemaCompatibility

public class AvroSchemaCompatibility
extends Object

Evaluate the compatibility between a reader schema and a writer schema. A reader and a writer schema are declared compatible if all datum instances of the writer schema can be successfully decoded using the specified reader schema.

NOTE: PLEASE READ CAREFULLY BEFORE CHANGING

This code is borrowed from Avro 1.10, with the following modifications:

1. Compatibility checks ignore schema name, unless schema is held inside a union

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AvroSchemaCompatibility.Incompatibility
static class	AvroSchemaCompatibility.SchemaCompatibilityResult Immutable class representing details about a particular schema pair compatibility check.
static class	AvroSchemaCompatibility.SchemaCompatibilityType Identifies the type of schema compatibility result.
static class	AvroSchemaCompatibility.SchemaIncompatibilityType
static class	AvroSchemaCompatibility.SchemaPairCompatibility Provides information about the compatibility of a single reader and writer schema pair.

Field Summary

Fields

Modifier and Type	Field and Description
static String	READER_WRITER_COMPATIBLE_MESSAGE Message to annotate reader/writer schema pairs that are compatible.

Method Summary

Modifier and Type	Method and Description
static AvroSchemaCompatibility.SchemaPairCompatibility	checkReaderWriterCompatibility(org.apache.avro.Schema reader, org.apache.avro.Schema writer, boolean checkNamingOverride) Validates that the provided reader schema can be used to decode avro data written with the provided writer schema.
static org.apache.avro.Schema.Field	lookupWriterField(org.apache.avro.Schema writerSchema, org.apache.avro.Schema.Field readerField) Identifies the writer field that corresponds to the specified reader field.
static boolean	schemaNameEquals(org.apache.avro.Schema reader, org.apache.avro.Schema writer) Tests the equality of two Avro named schemas.

Methods inherited from class java.lang.Object

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

Field Detail

READER_WRITER_COMPATIBLE_MESSAGE

public static final String READER_WRITER_COMPATIBLE_MESSAGE

Message to annotate reader/writer schema pairs that are compatible.

See Also:

Constant Field Values

Method Detail

checkReaderWriterCompatibility

public static AvroSchemaCompatibility.SchemaPairCompatibility checkReaderWriterCompatibility(org.apache.avro.Schema reader,
                                                                                             org.apache.avro.Schema writer,
                                                                                             boolean checkNamingOverride)

Validates that the provided reader schema can be used to decode avro data written with the provided writer schema.

Parameters:

reader - schema to check.

writer - schema to check.

Returns:

a result object identifying any compatibility errors.

schemaNameEquals

public static boolean schemaNameEquals(org.apache.avro.Schema reader,
                                       org.apache.avro.Schema writer)

Tests the equality of two Avro named schemas.

Matching includes reader name aliases.

Parameters:

reader - Named reader schema.

writer - Named writer schema.

Returns:

whether the names of the named schemas match or not.

lookupWriterField

public static org.apache.avro.Schema.Field lookupWriterField(org.apache.avro.Schema writerSchema,
                                                             org.apache.avro.Schema.Field readerField)

Identifies the writer field that corresponds to the specified reader field.

Matching includes reader name aliases.

Parameters:

writerSchema - Schema of the record where to look for the writer field.

readerField - Reader field to identify the corresponding writer field of.

Returns:

the writer field, if any does correspond, or None.