qiaojialin commented on a change in pull request #64: Add example module URL: https://github.com/apache/incubator-iotdb/pull/64#discussion_r259794344
########## File path: example/readme.md ########## @@ -0,0 +1,143 @@ +<!-- + + 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. + +--> +# 1. Kafka-IoTDB Demo +## Function +``` +The example is to show how to send data from localhost to IoTDB through Kafka. +``` +## Usage +### Version usage +IoTDB: 0.8.0-SNAPSHOT +Kafka: 0.8.2.0 +### Dependencies with Maven + +``` +<dependencies> + <dependency> + <groupId>org.apache.kafka</groupId> + <artifactId>kafka_2.10</artifactId> + <version>0.8.2.0</version> + </dependency> + <dependency> + <groupId>org.apache.iotdb</groupId> + <artifactId>iotdb-jdbc</artifactId> + <version>0.8.0-SNAPSHOT</version> + </dependency> +</dependencies> +``` + +### Launch the servers + +``` + Before you run the program, make sure you have launched the servers of Kafka and IoTDB. + For details, please refer to http://kafka.apache.org/081/documentation.html#quickstart +``` + +### Run KafkaProducer.java + +``` + The class is to send data from localhost to Kafka clusters. + Firstly, you have to change the parameter of TOPIC in Constant.java to what you create：(for example : "Kafka-Test") + > public final static String TOPIC = "Kafka-Test"; + The default format of data is "device,timestamp,value ". (for example : "sensor1,2017/10/24 19:30:00,60") + Then you need to create data in Constat.ALL_DATA + Finally, run KafkaProducer.java +``` + +### Run KafkaConsumer.java + +``` + The class is to show how to consume data from kafka through multi-threads. + The data is sent by class KafkaProducer. + You can set the parameter of CONSUMER_THREAD_NUM in Constant.java to make sure the number of consumer threads:(for example: "5") + > private final static int CONSUMER_THREAD_NUM = 5; +``` + +#### Notice + If you want to use multiple consumers, please make sure that the number of topic's partition you create is more than 1. + +# 2. Rocketmq-IoTDB Demo +##Introduction +This demo shows how to store data into IoTDB via rocketmq +##Basic Concept +The following basic concepts are involved in IoTDB: + +* Device + +A devices is an installation equipped with sensors in real scenarios. In IoTDB, all sensors should have their corresponding devices. + +* Sensor + +A sensor is a detection equipment in an actual scene, which can sense the information to be measured, and can transform the sensed information into an electrical signal or other desired form of information output and send it to IoTDB. In IoTDB, all data and paths stored are organized in units of sensors. + +* Storage Group + +Storage groups are used to let users define how to organize and isolate different time series data on disk. Time series belonging to the same storage group will be continuously written to the same file in the corresponding folder. The file may be closed due to user commands or system policies, and hence the data coming next from these sensors will be stored in a new file in the same folder. Time series belonging to different storage groups are stored in different folders. +##Connector +> note:In this sample program, there are some update operations for historical data, so it is necessary to ensure the sequential transmission and consumption of data via RocketMQ. If there is no update operation in use, then there is no need to guarantee the order of data. IoTDB will process these data which may be disorderly. + +###Producer +Producers insert IoTDB insert statements into partitions according to devices, ensuring that the same device's data is inserted or updated in the same MessageQueue. +###Consumer +1. At startup, consumer client first creates the JDBC connection and check whether storage groups and timeseries are created in IoTDB. If it is not created, create it. Review comment: ```suggestion 1. At startup, the consumer client first creates a JDBC connection and check whether the storage groups and timeseries are created in IoTDB. If not, create it. ``` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
