Examples with DataSchemaTraverse com.linkedin.data.schema.DataSchemaTraverse used on opensource projects

Example 1 with DataSchemaTraverse

use of com.linkedin.data.schema.DataSchemaTraverse in project rest.li by linkedin.

the class SchemaTranslator method dataToAvroSchemaJson.

/**
   * Translate from a {@link DataSchema} to an Avro {@link Schema}
   * <p>
   * This method translates optional fields in the {@link DataSchema} to union with null
   * fields in Avro {@link Schema}. Record fields with optional attribute set to true will
   * be translated to a union type that has null member type. If field's type is not
   * a union, then the new union type will be a union of the field's type and the null type.
   * If the field's type is already a union, the new union type contains all the
   * union's member types and the null type.
   * <p>
   * This method also translates or sets the default value for optional fields in
   * the {@link DataSchema}. If the optional field does not have a default value,
   * set the translated default value to null. {@link OptionalDefaultMode}
   * specifies how an optional field with a default value is translated.
   * <p>
   * Both the schema and default value translation takes into account that default value
   * representation for Avro unions does not include the member type discriminator and
   * the type of the default value is always the 1st member type of the union. Schema translation
   * fails by throwing an {@link IllegalArgumentException} if the default value's type
   * is not the same as the 1st member type of the union.
   * <p>
   * If {@link DataToAvroSchemaTranslationOptions#getEmbeddedSchema()} EmbeddedSchema()} is
   * set to {@link EmbedSchemaMode#ROOT_ONLY}, then the input {@link DataSchema} will be embedded in the
   * translated Avro {@link Schema}.
   * The embedded schema will be the value of the "schema" property within the "com.linkedin.data" property.
   * If the input {@link DataSchema} is a typeref, then embedded schema will be that of the
   * actual type referenced.
   *
   * @param dataSchema provides the {@link DataSchema}.
   * @param options specifies the {@link DataToAvroSchemaTranslationOptions}.
   * @return the JSON representation of the Avro {@link Schema}.
   * @throws IllegalArgumentException if the {@link DataSchema} cannot be translated.
   */
public static String dataToAvroSchemaJson(DataSchema dataSchema, DataToAvroSchemaTranslationOptions options) throws IllegalArgumentException {
    // convert default values
    DataSchemaTraverse postOrderTraverse = new DataSchemaTraverse(DataSchemaTraverse.Order.POST_ORDER);
    final DefaultDataToAvroConvertCallback defaultConverter = new DefaultDataToAvroConvertCallback(options);
    postOrderTraverse.traverse(dataSchema, defaultConverter);
    // convert schema
    String schemaJson = SchemaToAvroJsonEncoder.schemaToAvro(dataSchema, defaultConverter.fieldDefaultValueProvider(), options);
    return schemaJson;
}

Example 2 with DataSchemaTraverse

use of com.linkedin.data.schema.DataSchemaTraverse in project rest.li by linkedin.

the class DataSchemaAnnotationValidator method buildSchemaValidators.

/**
   * Build a cache of {@link Validator}s declared for the specified schema.
   *
   * @param schema to cache {@link Validator}s for.
   * @return the cache if successful.
   */
private IdentityHashMap<Object, List<Validator>> buildSchemaValidators(DataSchema schema) {
    final IdentityHashMap<Object, List<Validator>> map = new IdentityHashMap<Object, List<Validator>>();
    DataSchemaTraverse traverse = new DataSchemaTraverse();
    traverse.traverse(schema, new DataSchemaTraverse.Callback() {

        @Override
        public void callback(List<String> path, DataSchema schema) {
            List<Validator> validatorList = map.get(schema);
            if (validatorList == null) {
                Object validateObject = schema.getProperties().get(VALIDATE);
                if (validateObject == null) {
                    validatorList = NO_VALIDATORS;
                } else {
                    validatorList = buildValidatorList(validateObject, path, schema);
                }
                map.put(schema, validatorList);
                if (schema.getType() == DataSchema.Type.RECORD) {
                    RecordDataSchema recordDataSchema = (RecordDataSchema) schema;
                    for (RecordDataSchema.Field field : recordDataSchema.getFields()) {
                        validateObject = field.getProperties().get(VALIDATE);
                        if (validateObject == null) {
                            validatorList = NO_VALIDATORS;
                        } else {
                            path.add(field.getName());
                            validatorList = buildValidatorList(validateObject, path, field);
                            path.remove(path.size() - 1);
                        }
                        map.put(field, validatorList);
                    }
                }
            }
        }
    });
    return map;
}

Example 3 with DataSchemaTraverse

use of com.linkedin.data.schema.DataSchemaTraverse in project rest.li by linkedin.

the class SchemaTranslator method avroToDataSchema.

/**
   * Translate an Avro {@link Schema} to a {@link DataSchema}.
   * <p>
   * If the translation mode is {@link AvroToDataSchemaTranslationMode#RETURN_EMBEDDED_SCHEMA}
   * and a {@link DataSchema} is embedded in the Avro schema, then return the embedded schema.
   * An embedded schema is present if the Avro {@link Schema} has a "com.linkedin.data" property and the
   * "com.linkedin.data" property contains both "schema" and "optionalDefaultMode" properties.
   * The "schema" property provides the embedded {@link DataSchema}.
   * The "optionalDefaultMode" property provides how optional default values were translated.
   * <p>
   * If the translation mode is {@link AvroToDataSchemaTranslationMode#VERIFY_EMBEDDED_SCHEMA}
   * and a {@link DataSchema} is embedded in the Avro schema, then verify that the embedded schema
   * translates to the input Avro schema. If the translated and embedded schema is the same,
   * then return the embedded schema, else throw {@link IllegalArgumentException}.
   * <p>
   * If the translation mode is {@link com.linkedin.data.avro.AvroToDataSchemaTranslationMode#TRANSLATE}
   * or no embedded {@link DataSchema} is present, then this method
   * translates the provided Avro {@link Schema} to a {@link DataSchema}
   * as described follows:
   * <p>
   * This method translates union with null record fields in Avro {@link Schema}
   * to optional fields in {@link DataSchema}. Record fields
   * whose type is a union with null will be translated to a new type, and the field becomes optional.
   * If the Avro union has two types (one of them is the null type), then the new type of the
   * field is the non-null member type of the union. If the Avro union does not have two types
   * (one of them is the null type) then the new type of the field is a union type with the null type
   * removed from the original union.
   * <p>
   * This method also translates default values. If the field's type is a union with null
   * and has a default value, then this method also translates the default value of the field
   * to comply with the new type of the field. If the default value is null,
   * then remove the default value. If new type is not a union and the default value
   * is of the non-null member type, then assign the default value to the
   * non-null value within the union value (i.e. the value of the only entry within the
   * JSON object.) If the new type is a union and the default value is of the
   * non-null member type, then assign the default value to a JSON object
   * containing a single entry with the key being the member type discriminator of
   * the first union member and the value being the actual member value.
   * <p>
   * Both the schema and default value translation takes into account that default value
   * representation for Avro unions does not include the member type discriminator and
   * the type of the default value is always the 1st member of the union.
   *
   * @param avroSchemaInJson provides the JSON representation of the Avro {@link Schema}.
   * @param options specifies the {@link AvroToDataSchemaTranslationOptions}.
   * @return the translated {@link DataSchema}.
   * @throws IllegalArgumentException if the Avro {@link Schema} cannot be translated.
   */
public static DataSchema avroToDataSchema(String avroSchemaInJson, AvroToDataSchemaTranslationOptions options) throws IllegalArgumentException {
    ValidationOptions validationOptions = SchemaParser.getDefaultSchemaParserValidationOptions();
    validationOptions.setAvroUnionMode(true);
    SchemaParserFactory parserFactory = SchemaParserFactory.instance(validationOptions);
    DataSchemaResolver resolver = getResolver(parserFactory, options);
    PegasusSchemaParser parser = parserFactory.create(resolver);
    parser.parse(avroSchemaInJson);
    if (parser.hasError()) {
        throw new IllegalArgumentException(parser.errorMessage());
    }
    assert (parser.topLevelDataSchemas().size() == 1);
    DataSchema dataSchema = parser.topLevelDataSchemas().get(0);
    DataSchema resultDataSchema = null;
    AvroToDataSchemaTranslationMode translationMode = options.getTranslationMode();
    if (translationMode == AvroToDataSchemaTranslationMode.RETURN_EMBEDDED_SCHEMA || translationMode == AvroToDataSchemaTranslationMode.VERIFY_EMBEDDED_SCHEMA) {
        // check for embedded schema
        Object dataProperty = dataSchema.getProperties().get(SchemaTranslator.DATA_PROPERTY);
        if (dataProperty != null && dataProperty.getClass() == DataMap.class) {
            Object schemaProperty = ((DataMap) dataProperty).get(SchemaTranslator.SCHEMA_PROPERTY);
            if (schemaProperty.getClass() == DataMap.class) {
                SchemaParser embeddedSchemaParser = SchemaParserFactory.instance().create(null);
                embeddedSchemaParser.parse(Arrays.asList(schemaProperty));
                if (embeddedSchemaParser.hasError()) {
                    throw new IllegalArgumentException("Embedded schema is invalid\n" + embeddedSchemaParser.errorMessage());
                }
                assert (embeddedSchemaParser.topLevelDataSchemas().size() == 1);
                resultDataSchema = embeddedSchemaParser.topLevelDataSchemas().get(0);
                if (translationMode == AvroToDataSchemaTranslationMode.VERIFY_EMBEDDED_SCHEMA) {
                    // additional verification to make sure that embedded schema translates to Avro schema
                    DataToAvroSchemaTranslationOptions dataToAvdoSchemaOptions = new DataToAvroSchemaTranslationOptions();
                    Object optionalDefaultModeProperty = ((DataMap) dataProperty).get(SchemaTranslator.OPTIONAL_DEFAULT_MODE_PROPERTY);
                    dataToAvdoSchemaOptions.setOptionalDefaultMode(OptionalDefaultMode.valueOf(optionalDefaultModeProperty.toString()));
                    Schema avroSchemaFromEmbedded = dataToAvroSchema(resultDataSchema, dataToAvdoSchemaOptions);
                    Schema avroSchemaFromJson = Schema.parse(avroSchemaInJson);
                    if (avroSchemaFromEmbedded.equals(avroSchemaFromJson) == false) {
                        throw new IllegalArgumentException("Embedded schema does not translate to input Avro schema: " + avroSchemaInJson);
                    }
                }
            }
        }
    }
    if (resultDataSchema == null) {
        // translationMode == TRANSLATE or no embedded schema
        DataSchemaTraverse traverse = new DataSchemaTraverse();
        traverse.traverse(dataSchema, AvroToDataSchemaConvertCallback.INSTANCE);
        // convert default values
        traverse.traverse(dataSchema, DefaultAvroToDataConvertCallback.INSTANCE);
        // make sure it can round-trip
        String dataSchemaJson = dataSchema.toString();
        resultDataSchema = DataTemplateUtil.parseSchema(dataSchemaJson);
    }
    return resultDataSchema;
}

Example 4 with DataSchemaTraverse

use of com.linkedin.data.schema.DataSchemaTraverse in project rest.li by linkedin.

the class RestLiResourceRelationship method findDataModels.

private void findDataModels() {
    final ResourceSchemaVisitior visitor = new BaseResourceSchemaVisitor() {

        @Override
        public void visitResourceSchema(VisitContext visitContext, ResourceSchema resourceSchema) {
            final String schema = resourceSchema.getSchema();
            // ActionSet resources do not have a schema
            if (schema != null) {
                final NamedDataSchema schemaSchema = extractSchema(schema);
                if (schemaSchema != null) {
                    connectSchemaToResource(visitContext, schemaSchema);
                }
            }
        }

        @Override
        public void visitCollectionResource(VisitContext visitContext, CollectionSchema collectionSchema) {
            final IdentifierSchema id = collectionSchema.getIdentifier();
            final NamedDataSchema typeSchema = extractSchema(id.getType());
            if (typeSchema != null) {
                connectSchemaToResource(visitContext, typeSchema);
            }
            final String params = id.getParams();
            if (params != null) {
                final NamedDataSchema paramsSchema = extractSchema(params);
                if (paramsSchema != null) {
                    connectSchemaToResource(visitContext, paramsSchema);
                }
            }
        }

        @Override
        public void visitAssociationResource(VisitContext visitContext, AssociationSchema associationSchema) {
            for (AssocKeySchema key : associationSchema.getAssocKeys()) {
                final NamedDataSchema keyTypeSchema = extractSchema(key.getType());
                if (keyTypeSchema != null) {
                    connectSchemaToResource(visitContext, keyTypeSchema);
                }
            }
        }

        @Override
        public void visitParameter(VisitContext visitContext, RecordTemplate parentResource, Object parentMethodSchema, ParameterSchema parameterSchema) {
            String parameterTypeString = parameterSchema.getType();
            if (// the parameter type field contains a inline schema, so we traverse into it
            isInlineSchema(parameterTypeString)) {
                visitInlineSchema(visitContext, parameterTypeString);
            } else {
                final NamedDataSchema schema;
                // grab the schema name from it
                if (parameterSchema.hasItems()) {
                    schema = extractSchema(parameterSchema.getItems());
                } else // the only remaining possibility is that the type field contains the name of a data schema
                {
                    schema = extractSchema(parameterTypeString);
                }
                if (schema != null) {
                    connectSchemaToResource(visitContext, schema);
                }
            }
        }

        @Override
        public void visitFinder(VisitContext visitContext, RecordTemplate parentResource, FinderSchema finderSchema) {
            final MetadataSchema metadata = finderSchema.getMetadata();
            if (metadata != null) {
                final NamedDataSchema metadataTypeSchema = extractSchema(metadata.getType());
                if (metadataTypeSchema != null) {
                    connectSchemaToResource(visitContext, metadataTypeSchema);
                }
            }
        }

        @Override
        public void visitAction(VisitContext visitContext, RecordTemplate parentResource, ResourceLevel resourceLevel, ActionSchema actionSchema) {
            final String returns = actionSchema.getReturns();
            if (returns != null) {
                if (// the parameter type field contains a inline schema, so we traverse into it
                isInlineSchema(returns)) {
                    visitInlineSchema(visitContext, returns);
                } else // otherwise the type field contains the name of a data schema
                {
                    final NamedDataSchema returnsSchema = extractSchema(returns);
                    if (returnsSchema != null) {
                        connectSchemaToResource(visitContext, returnsSchema);
                    }
                }
            }
            final StringArray throwsArray = actionSchema.getThrows();
            if (throwsArray != null) {
                for (String errorName : throwsArray) {
                    final NamedDataSchema errorSchema = extractSchema(errorName);
                    if (errorSchema != null) {
                        connectSchemaToResource(visitContext, errorSchema);
                    }
                }
            }
        }

        private boolean isInlineSchema(String schemaString) {
            return schemaString.startsWith("{");
        }

        private void visitInlineSchema(VisitContext visitContext, String schemaString) {
            DataSchema schema = DataTemplateUtil.parseSchema(schemaString, _schemaResolver);
            if (schema instanceof ArrayDataSchema) {
                DataSchema itemSchema = ((ArrayDataSchema) schema).getItems();
                if (itemSchema instanceof NamedDataSchema) {
                    connectSchemaToResource(visitContext, (NamedDataSchema) itemSchema);
                }
            }
            if (schema instanceof MapDataSchema) {
                DataSchema valueSchema = ((MapDataSchema) schema).getValues();
                if (valueSchema instanceof NamedDataSchema) {
                    connectSchemaToResource(visitContext, (NamedDataSchema) valueSchema);
                }
            }
        }

        private void connectSchemaToResource(VisitContext visitContext, final NamedDataSchema schema) {
            final Node<NamedDataSchema> schemaNode = _relationships.get(schema);
            _dataModels.put(schema.getFullName(), schema);
            final DataSchemaTraverse traveler = new DataSchemaTraverse();
            traveler.traverse(schema, new DataSchemaTraverse.Callback() {

                @Override
                public void callback(List<String> path, DataSchema nestedSchema) {
                    if (nestedSchema instanceof RecordDataSchema && nestedSchema != schema) {
                        final RecordDataSchema nestedRecordSchema = (RecordDataSchema) nestedSchema;
                        _dataModels.put(nestedRecordSchema.getFullName(), nestedRecordSchema);
                        final Node<RecordDataSchema> node = _relationships.get(nestedRecordSchema);
                        schemaNode.addAdjacentNode(node);
                    }
                }
            });
            final Node<ResourceSchema> resourceNode = _relationships.get(visitContext.getParentSchema());
            resourceNode.addAdjacentNode(schemaNode);
            schemaNode.addAdjacentNode(resourceNode);
        }
    };
    ResourceSchemaCollection.visitResources(_resourceSchemas.getResources().values(), visitor);
}