Github user MikeThomsen commented on a diff in the pull request:
https://github.com/apache/nifi/pull/2562#discussion_r178329293
--- Diff:
nifi-nar-bundles/nifi-influxdb-bundle/nifi-influxdb-processors/src/main/java/org/apache/nifi/processors/influxdb/ExecuteInfluxDBQuery.java
---
@@ -0,0 +1,258 @@
+/*
+ * 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.influxdb;
+import org.apache.nifi.annotation.behavior.EventDriven;
+import org.apache.nifi.annotation.behavior.InputRequirement;
+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.documentation.CapabilityDescription;
+import org.apache.nifi.annotation.documentation.Tags;
+import org.apache.nifi.annotation.lifecycle.OnScheduled;
+import org.apache.nifi.annotation.lifecycle.OnStopped;
+import org.apache.nifi.components.PropertyDescriptor;
+import org.apache.nifi.flowfile.FlowFile;
+import org.apache.nifi.processor.ProcessContext;
+import org.apache.nifi.processor.ProcessSession;
+import org.apache.nifi.processor.Relationship;
+import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.processor.util.StandardValidators;
+import org.influxdb.dto.Query;
+import org.influxdb.dto.QueryResult;
+import com.google.gson.Gson;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.net.SocketTimeoutException;
+import java.nio.charset.Charset;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+
+@InputRequirement(InputRequirement.Requirement.INPUT_ALLOWED)
+@EventDriven
+@SupportsBatching
+@Tags({"influxdb", "measurement", "get", "read", "query", "timeseries"})
+@CapabilityDescription("Processor to execute InfluxDB query from the
content of a FlowFile (preferred) or a scheduled query. Please check details
of the supported queries in InfluxDB documentation
(https://www.influxdb.com/).")
+@WritesAttributes({
+ @WritesAttribute(attribute =
AbstractInfluxDBProcessor.INFLUX_DB_ERROR_MESSAGE, description = "InfluxDB
error message"),
+ @WritesAttribute(attribute =
ExecuteInfluxDBQuery.INFLUX_DB_EXECUTED_QUERY, description = "InfluxDB executed
query"),
+ })
+public class ExecuteInfluxDBQuery extends AbstractInfluxDBProcessor {
+
+ public static final String INFLUX_DB_EXECUTED_QUERY =
"influxdb.executed.query";
+
+ public static final PropertyDescriptor INFLUX_DB_QUERY_RESULT_TIMEUNIT
= new PropertyDescriptor.Builder()
+ .name("influxdb-query-result-time-unit")
+ .displayName("Query Result Time Units")
+ .description("The time unit of query results from the
InfluxDB")
+ .defaultValue(TimeUnit.NANOSECONDS.name())
+ .required(true)
+ .expressionLanguageSupported(true)
+ .allowableValues(Arrays.stream(TimeUnit.values()).map( v ->
v.name()).collect(Collectors.toSet()))
+ .sensitive(false)
+ .build();
+
+ public static final PropertyDescriptor INFLUX_DB_QUERY = new
PropertyDescriptor.Builder()
+ .name("influxdb-query")
+ .displayName("InfluxDB Query")
+ .description("The InfluxDB query to execute. "
+ + "Note: If there are incoming connections, then the
query is created from incoming FlowFile's content and scheduled query is
ignored.")
+ .required(false)
+ .addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
+ .expressionLanguageSupported(true)
+ .build();
+
+ static final Relationship REL_SUCCESS = new
Relationship.Builder().name("success")
+ .description("Successful InfluxDB queries are routed to this
relationship").build();
+
+ static final Relationship REL_FAILURE = new
Relationship.Builder().name("failure")
+ .description("Falied InfluxDB queries are routed to this
relationship").build();
+
+ static final Relationship REL_RETRY = new
Relationship.Builder().name("retry")
+ .description("Failed queries that are retryable exception are
routed to this relationship").build();
+
+ private static final Set<Relationship> relationships;
+ private static final List<PropertyDescriptor> propertyDescriptors;
+ protected Gson gson = new Gson();
+
+ static {
+ final Set<Relationship> tempRelationships = new HashSet<>();
+ tempRelationships.add(REL_SUCCESS);
+ tempRelationships.add(REL_FAILURE);
+ tempRelationships.add(REL_RETRY);
+ relationships = Collections.unmodifiableSet(tempRelationships);
+ final List<PropertyDescriptor> tempDescriptors = new ArrayList<>();
+ tempDescriptors.add(DB_NAME);
+ tempDescriptors.add(INFLUX_DB_URL);
+ tempDescriptors.add(INFLUX_DB_CONNECTION_TIMEOUT);
+ tempDescriptors.add(INFLUX_DB_QUERY_RESULT_TIMEUNIT);
+ tempDescriptors.add(INFLUX_DB_QUERY);
+ tempDescriptors.add(USERNAME);
+ tempDescriptors.add(PASSWORD);
+ tempDescriptors.add(CHARSET);
+ propertyDescriptors =
Collections.unmodifiableList(tempDescriptors);
+ }
+
+ @Override
+ public Set<Relationship> getRelationships() {
+ return relationships;
+ }
+
+ @Override
+ public final List<PropertyDescriptor>
getSupportedPropertyDescriptors() {
+ return propertyDescriptors;
+ }
+
+ @OnScheduled
+ public void onScheduled(final ProcessContext context) {
+ super.onScheduled(context);
+ // Either input connection or scheduled query is required
+ if ( ! context.getProperty(INFLUX_DB_QUERY).isSet()
+ && ! context.hasIncomingConnection() ) {
+ String error = "The InfluxDB Query processor requires input
connection or scheduled InfluxDB query";
+ getLogger().error(error);
+ throw new ProcessException(error);
+ }
+ }
+
+ @Override
+ public void onTrigger(final ProcessContext context, final
ProcessSession session) throws ProcessException {
+
+ String query = null;
+ String database = null;
+ TimeUnit queryResultTimeunit = null;
+ Charset charset = null;
+ FlowFile outgoingFlowFile = null;
+
+ // If there are incoming connections, prepare query params from
flow file
+ if ( context.hasIncomingConnection() ) {
+ FlowFile incomingFlowFile = session.get();
+
+ if ( incomingFlowFile == null &&
context.hasNonLoopConnection() ) {
+ return;
+ }
+
+ if ( incomingFlowFile.getSize() == 0) {
+ getLogger().error("Empty query");
+ incomingFlowFile = session.putAttribute(incomingFlowFile,
INFLUX_DB_ERROR_MESSAGE, "Empty query size is " + incomingFlowFile.getSize());
+ session.transfer(incomingFlowFile, REL_FAILURE);
+ return;
+ }
+
+ charset =
Charset.forName(context.getProperty(CHARSET).evaluateAttributeExpressions(incomingFlowFile).getValue());
+ try {
+ ByteArrayOutputStream baos = new ByteArrayOutputStream();
+ session.exportTo(incomingFlowFile, baos);
+ baos.close();
+ query = new String(baos.toByteArray(), charset);
+ } catch(IOException ioe) {
+ getLogger().error("Exception while reading from FlowFile "
+ ioe.getLocalizedMessage(), ioe);
+ throw new ProcessException(ioe);
+ }
+
+ database =
context.getProperty(DB_NAME).evaluateAttributeExpressions(incomingFlowFile).getValue();
+ queryResultTimeunit =
TimeUnit.valueOf(context.getProperty(INFLUX_DB_QUERY_RESULT_TIMEUNIT).evaluateAttributeExpressions(incomingFlowFile).getValue());
+
+ outgoingFlowFile = incomingFlowFile;
+ } else {
+ charset =
Charset.forName(context.getProperty(CHARSET).evaluateAttributeExpressions().getValue());
+ query =
context.getProperty(INFLUX_DB_QUERY).evaluateAttributeExpressions().getValue();
+ database =
context.getProperty(DB_NAME).evaluateAttributeExpressions().getValue();
+ queryResultTimeunit =
TimeUnit.valueOf(context.getProperty(INFLUX_DB_QUERY_RESULT_TIMEUNIT).evaluateAttributeExpressions().getValue());
+
+ outgoingFlowFile = session.create();
+ }
+
+ try {
+ long startTimeMillis = System.currentTimeMillis();
+ QueryResult result = executeQuery(context, database, query,
queryResultTimeunit);
+
+ if ( result == null ) {
+ String message = "Query Result was " + result;
+ getLogger().error(message);
+ throw new NullPointerException(message);
+ }
+
+ String json = gson.toJson(result);
+
+ if ( getLogger().isDebugEnabled() ) {
+ getLogger().debug("Query result {} ", new Object[]
{result});
+ }
+
+ ByteArrayInputStream bais = new
ByteArrayInputStream(json.getBytes(charset));
+ session.importFrom(bais, outgoingFlowFile);
+ bais.close();
+
+ final long endTimeMillis = System.currentTimeMillis();
+
+ if ( ! result.hasError() ) {
+ outgoingFlowFile = session.putAttribute(outgoingFlowFile,
INFLUX_DB_EXECUTED_QUERY, String.valueOf(query));
--- End diff --
You might want to put this on the failure scenario too because there could
be syntax errors getting reported. This is especially going to be helpful if
the user is dynamically generating the query.
---
