exceptionfactory commented on a change in pull request #5326: URL: https://github.com/apache/nifi/pull/5326#discussion_r696815399
########## File path: nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/ValidateJson.java ########## @@ -0,0 +1,203 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.nifi.processors.standard; + +import org.apache.nifi.components.AllowableValue; +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.expression.ExpressionLanguageScope; +import org.apache.nifi.flowfile.FlowFile; +import org.apache.nifi.annotation.behavior.EventDriven; +import org.apache.nifi.annotation.behavior.InputRequirement; +import org.apache.nifi.annotation.behavior.SideEffectFree; +import org.apache.nifi.annotation.behavior.SupportsBatching; +import org.apache.nifi.annotation.behavior.WritesAttribute; +import org.apache.nifi.annotation.behavior.WritesAttributes; +import org.apache.nifi.annotation.behavior.InputRequirement.Requirement; +import org.apache.nifi.annotation.documentation.CapabilityDescription; +import org.apache.nifi.annotation.documentation.Tags; +import org.apache.nifi.annotation.lifecycle.OnScheduled; +import org.apache.nifi.processor.exception.ProcessException; +import org.apache.nifi.processor.AbstractProcessor; +import org.apache.nifi.processor.ProcessContext; +import org.apache.nifi.processor.ProcessSession; +import org.apache.nifi.processor.ProcessorInitializationContext; +import org.apache.nifi.processor.Relationship; +import org.apache.nifi.processor.util.StandardValidators; + +import java.io.IOException; +import java.io.InputStream; +import java.util.ArrayList; +import java.util.Collections; +import java.util.HashSet; +import java.util.List; +import java.util.Set; + +import com.fasterxml.jackson.databind.JsonNode; +import com.fasterxml.jackson.databind.ObjectMapper; +import com.networknt.schema.JsonSchema; +import com.networknt.schema.JsonSchemaFactory; +import com.networknt.schema.ValidationMessage; +import com.networknt.schema.SpecVersion.VersionFlag; + +@EventDriven +@SideEffectFree +@SupportsBatching +@InputRequirement(Requirement.INPUT_REQUIRED) +@Tags({"JSON", "schema", "validation"}) +@WritesAttributes({ + @WritesAttribute(attribute = "validatejson.invalid.error", description = "If the flow file is routed to the invalid relationship " + + "the attribute will contain the error message resulting from the validation failure.") +}) +@CapabilityDescription("Validates the contents of FlowFiles against a user-specified JSON Schema file") +public class ValidateJson extends AbstractProcessor { + + public static final String ERROR_ATTRIBUTE_KEY = "validatejson.invalid.error"; + + public static final AllowableValue SCHEMA_VERSION_4 = new AllowableValue("V4"); + public static final AllowableValue SCHEMA_VERSION_6 = new AllowableValue("V6"); + public static final AllowableValue SCHEMA_VERSION_7 = new AllowableValue("V7"); + public static final AllowableValue SCHEMA_VERSION_V201909 = new AllowableValue("V201909"); + + public static final PropertyDescriptor SCHEMA_VERSION = new PropertyDescriptor + .Builder().name("SCHEMA_VERSION") + .displayName("Schema Version") + .description("The JSON schema specification") + .required(true) + .allowableValues(SCHEMA_VERSION_4, SCHEMA_VERSION_6, SCHEMA_VERSION_7, SCHEMA_VERSION_V201909) + .defaultValue(SCHEMA_VERSION_V201909.getValue()) + .build(); + + public static final PropertyDescriptor SCHEMA_TEXT = new PropertyDescriptor + .Builder().name("SCHEMA_TEXT") + .displayName("Schema Text") + .description("The text of a JSON schema") + .required(true) + .expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .build(); + + public static final Relationship REL_VALID = new Relationship.Builder() + .name("valid") + .description("FlowFiles that are successfully validated against the schema are routed to this relationship") + .build(); + + public static final Relationship REL_INVALID = new Relationship.Builder() + .name("invalid") + .description("FlowFiles that are not valid according to the specified schema are routed to this relationship") + .build(); + + public static final Relationship REL_FAILURE = new Relationship.Builder() + .name("failure") + .description("FlowFiles that cannot be read as JSON are routed to this relationship") + .build(); + + private List<PropertyDescriptor> descriptors; + + private Set<Relationship> relationships; + + private List<AllowableValue> allowableValues; + + @Override + protected void init(final ProcessorInitializationContext context) { + final List<PropertyDescriptor> descriptors = new ArrayList<PropertyDescriptor>(); + descriptors.add(SCHEMA_TEXT); + descriptors.add(SCHEMA_VERSION); + this.descriptors = Collections.unmodifiableList(descriptors); + + final Set<Relationship> relationships = new HashSet<Relationship>(); + relationships.add(REL_VALID); + relationships.add(REL_INVALID); + relationships.add(REL_FAILURE); + this.relationships = Collections.unmodifiableSet(relationships); + + final List<AllowableValue> allowableValues = new ArrayList<AllowableValue>(); + allowableValues.add(SCHEMA_VERSION_4); + allowableValues.add(SCHEMA_VERSION_6); + allowableValues.add(SCHEMA_VERSION_7); + allowableValues.add(SCHEMA_VERSION_V201909); + this.allowableValues = Collections.unmodifiableList(allowableValues); + + } + + @Override + public Set<Relationship> getRelationships() { + return this.relationships; + } + + @Override + public final List<PropertyDescriptor> getSupportedPropertyDescriptors() { + return descriptors; + } + + private ObjectMapper mapper = new ObjectMapper(); + private VersionFlag schemaVersion; + + @OnScheduled + public void onScheduled(final ProcessContext context) { + // Set JSON schema version to use from processor property + this.schemaVersion = VersionFlag.V201909; + if (context.getProperty(SCHEMA_VERSION).getValue() == SCHEMA_VERSION_4.getValue()) { + this.schemaVersion = VersionFlag.V4; + } + if (context.getProperty(SCHEMA_VERSION).getValue() == SCHEMA_VERSION_6.getValue()) { + this.schemaVersion = VersionFlag.V6; + } + if (context.getProperty(SCHEMA_VERSION).getValue() == SCHEMA_VERSION_7.getValue()) { + this.schemaVersion = VersionFlag.V7; + } + if (context.getProperty(SCHEMA_VERSION).getValue() == SCHEMA_VERSION_V201909.getValue()) { + this.schemaVersion = VersionFlag.V201909; + } + } + + + @Override + public void onTrigger(final ProcessContext context, final ProcessSession session) throws ProcessException { + FlowFile flowFile = session.get(); + if ( flowFile == null ) { + return; + } + + try (InputStream in = session.read(flowFile)) { + // Read in flowFile inputstream, and validate against schema + JsonNode node = mapper.readTree(in); + String schemaText = context.getProperty(SCHEMA_TEXT).evaluateAttributeExpressions().getValue(); + JsonSchemaFactory factory = JsonSchemaFactory.getInstance(schemaVersion); Review comment: The [project documentation]( https://github.com/networknt/json-schema-validator/blob/master/doc/cust-fetcher.md) indicates that there is a default [URLFetcher](https://github.com/networknt/json-schema-validator/blob/c41df270a71f8423c63cfaa379d2e9b3f570b73e/src/main/java/com/networknt/schema/uri/URLFetcher.java) configured to make network requests when encountering schemas with URI references. Although this may be acceptable in some cases, it also seems like something that should be possible to disable in deployments where external URI retrieval is not desired. Overriding the default behavior would require a custom `URIFetcher` implementation, but it would be a very helpful addition. In light of this being the default behavior, perhaps a property named `URI Fetcher` with allowable values of `DEFAULT` and `DISABLED` would be a good starting point. Using an enumerated list of values would provide the option for potential future implementations. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
