org.wikimedia.eventutilities.core.event.types

Interface SchemaConversions<T>

Type Parameters:

T - Parent schema type. E.g. Flink DataType or TypeInformation, or Spark DataType. TO DO: Implement support for String to Timestamp conversion. https://phabricator.wikimedia.org/T310495 https://phabricator.wikimedia.org/T278467

@ParametersAreNonnullByDefault
public interface SchemaConversions<T>

Interface for supported WMF Event Schema type conversions. This is used to map to a particular schema container, e.g. Flink DataTypes or Spark DataTypes. An implementation should return the appropriate T for the given method. E.g. Flink DataType: typeString() to DataTypes.STRING(), or Spark: typeString() to DataTypes.StringType

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	SchemaConversions.RowField<T> Data Transfer Object wrapper for a 'row field' type.

Method Summary

Modifier and Type	Method and Description
T	typeArray(T elementType, boolean elementsAreNullable) Returns type that represents Array.
T	typeBoolean() Returns type that represents boolean.
T	typeDecimal() Returns type that represents decimal.
T	typeInteger() Returns type that represents integer.
T	typeMap(T keyType, T valueType, boolean valuesAreNullable) Returns type that represents Map.
T	typeNull() Returns type that represents null.
T	typeRow(List<SchemaConversions.RowField<T>> rowFields) Returns type that represents a row AKA a struct AKA a JSON object.
T	typeString() Returns type that represents String.
T	typeTimestamp() Returns type that represents timestamps.

Method Detail

typeNull

@Nonnull
T typeNull()

Returns type that represents null.

typeBoolean

@Nonnull
T typeBoolean()

Returns type that represents boolean.

typeString

@Nonnull
T typeString()

Returns type that represents String.

typeInteger

@Nonnull
T typeInteger()

Returns type that represents integer.

typeDecimal

@Nonnull
T typeDecimal()

Returns type that represents decimal.

typeTimestamp

@Nonnull
T typeTimestamp()

Returns type that represents timestamps.

typeMap

@Nonnull
T typeMap(T keyType,
                   T valueType,
                   boolean valuesAreNullable)

Returns type that represents Map.

Parameters:

keyType - type of the Map keys.

valueType - type of the Map values.

valuesAreNullable - Whether Map values are possibly null.

typeArray

@Nonnull
T typeArray(T elementType,
                     boolean elementsAreNullable)

Returns type that represents Array.

Parameters:

elementType - type of the Array elements.

elementsAreNullable - Whether Array elements are possibly null.

typeRow

@Nonnull
T typeRow(List<SchemaConversions.RowField<T>> rowFields)

Returns type that represents a row AKA a struct AKA a JSON object. Rows have strictly defined field names and types. A RowField may or may not be nullable, and it may have a description.

Parameters:

rowFields - List of SchemaConversions.RowFields in this row. Use these to construct your row type.