am-c-p-p commented on a change in pull request #656: MINIFI-1013 Used soci library. URL: https://github.com/apache/nifi-minifi-cpp/pull/656#discussion_r358633260
########## File path: extensions/sql/processors/QueryDatabaseTable.cpp ########## @@ -0,0 +1,453 @@ +/** + * @file QueryDatabaseTable.cpp + * PutSQL class declaration + * + * 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. + */ + +#include "QueryDatabaseTable.h" + +#include <vector> +#include <queue> +#include <map> +#include <set> +#include <sstream> +#include <stdio.h> +#include <string> +#include <iostream> +#include <memory> +#include <codecvt> +#include <algorithm> +#include <regex> +#include <soci.h> + +#include "io/DataStream.h" +#include "core/ProcessContext.h" +#include "core/ProcessSession.h" +#include "Exception.h" +#include "utils/OsUtils.h" +#include "data/DatabaseConnectors.h" +#include "data/JSONSQLWriter.h" +#include "data/WriteCallback.h" +#include "data/MaxCollector.h" +#include "data/Utils.h" +#include "utils/file/FileUtils.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace processors { + +const std::string QueryDatabaseTable::ProcessorName("QueryDatabaseTable"); + +static const core::Property s_dbControllerService( + core::PropertyBuilder::createProperty("DB Controller Service")->isRequired(true)->withDescription("Database Controller Service.")->supportsExpressionLanguage(true)->build()); + +static const core::Property s_tableName( + core::PropertyBuilder::createProperty("Table Name")->isRequired(true)->withDescription("The name of the database table to be queried.")->supportsExpressionLanguage(true)->build()); + +static const core::Property s_columnNames( + core::PropertyBuilder::createProperty("Columns to Return")->isRequired(false)->withDescription( + "A comma-separated list of column names to be used in the query. If your database requires special treatment of the names (quoting, e.g.), each name should include such treatment. " + "If no column names are supplied, all columns in the specified table will be returned. " + "NOTE: It is important to use consistent column names for a given table for incremental fetch to work properly.")->supportsExpressionLanguage(true)->build()); + +static const core::Property s_maxValueColumnNames( + core::PropertyBuilder::createProperty("Maximum-value Columns")->isRequired(false)->withDescription( + "A comma-separated list of column names. The processor will keep track of the maximum value for each column that has been returned since the processor started running. " + "Using multiple columns implies an order to the column list, and each column's values are expected to increase more slowly than the previous columns' values. " + "Thus, using multiple columns implies a hierarchical structure of columns, which is usually used for partitioning tables. " + "This processor can be used to retrieve only those rows that have been added/updated since the last retrieval. " + "Note that some ODBC types such as bit/boolean are not conducive to maintaining maximum value, so columns of these types should not be listed in this property, and will result in error(s) during processing. " + "If no columns are provided, all rows from the table will be considered, which could have a performance impact. " + "NOTE: It is important to use consistent max-value column names for a given table for incremental fetch to work properly.")->supportsExpressionLanguage(true)->build()); + +static const core::Property s_whereClause( + core::PropertyBuilder::createProperty("db-fetch-where-clause")->isRequired(false)->withDescription( + "A custom clause to be added in the WHERE condition when building SQL queries.")->supportsExpressionLanguage(true)->build()); + +static const core::Property s_sqlQuery( + core::PropertyBuilder::createProperty("db-fetch-sql-query")->isRequired(false)->withDescription( + "A custom SQL query used to retrieve data. Instead of building a SQL query from other properties, this query will be wrapped as a sub-query. " + "Query must have no ORDER BY statement.")->supportsExpressionLanguage(true)->build()); + +static const core::Property s_maxRowsPerFlowFile( + core::PropertyBuilder::createProperty("qdbt-max-rows")->isRequired(true)->withDefaultValue<int>(0)->withDescription( + "The maximum number of result rows that will be included in a single FlowFile. This will allow you to break up very large result sets into multiple FlowFiles. " + "If the value specified is zero, then all rows are returned in a single FlowFile.")->supportsExpressionLanguage(true)->build()); + +static core::Property s_stateDirectory( + core::PropertyBuilder::createProperty("State Directory")->isRequired(false)->withDefaultValue("QDTState")->withDescription("Directory which contains processor state data.")->build()); + +static const core::Relationship s_success("success", "Successfully created FlowFile from SQL query result set."); + +// Probably need to have `FragmentAttributes` like nifi has https://github.com/apache/nifi/blob/master/nifi-commons/nifi-utils/src/main/java/org/apache/nifi/flowfile/attributes/FragmentAttributes.java. +static const std::string FragmentId = "fragment.identifier"; +static const std::string FragmentIndex = "fragment.index"; +static const std::string FragmentCount = "fragment.count"; + +// State +class State { + public: + State(const std::string& stateDir, const std::string& uuid, std::shared_ptr<logging::Logger> logger) + :logger_(logger) { + if (!createUUIDDir(stateDir, uuid, filePath_)) { + return; + } + + filePath_ += "State.txt"; + + if (!getStateFromFile()) { + return; + } + + ok_ = true; + } + + State::~State() { + if (file_.is_open()) { + file_.close(); + } + } + + operator bool() const { + return ok_; + } + + std::unordered_map<std::string, std::string> mapState() const { + return mapState_; + } + + bool writeStateToFile(const std::unordered_map<std::string, std::string>& mapState) { + file_.seekp(std::ios::beg); + + auto dataSize = 0; + for (const auto& el : mapState) { + file_ << el.first << '=' << el.second << separator(); + dataSize += el.first.size() + 1 + el.second.size() + separator().size(); + } + + // Clear old data with ' '. + for (auto i = dataSize_ - dataSize; i > 0; i--) { + file_ << ' '; + } + dataSize_ = dataSize; + + file_.flush(); + + mapState_ = mapState; + } + + private: + static const std::string& separator() { + static const std::string s_separator = "@!qdt!@"; + return s_separator; + } + + bool createUUIDDir(const std::string& stateDir, const std::string& uuid, std::string& dir) + { + if (stateDir.empty()) { + dir.clear(); + return false; + } + + auto dirWithBackslash = stateDir; + if (stateDir.back() != '\\') { + dirWithBackslash += '\\'; + } + + dir = dirWithBackslash + "uuid\\" + uuid + "\\"; Review comment: Fixed. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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