Interconnecting FlinkServer with Hive

Scenario

Currently, FlinkServer interconnects with Hive MetaStore. Therefore, the MetaStore function must be enabled for Hive. Hive can be used as source, sink, and dimension tables.

If your Kafka cluster is in security mode, the following example SQL statements can be used.

Prerequisites

Services such as HDFS, Yarn, Kafka, Flink, and Hive have been installed in the cluster.
The client that contains the Hive service has been installed, for example, in the /opt/Bigdata/client directory.
Flink 1.12.2 or later and Hive 3.1.0 or later are supported.
You have created a user with FlinkServer Admin Privilege, for example, flink_admin, to access the Flink web UI. For details, see Authentication Based on Users and Roles.
You have obtained the client configuration file and credential of the user for accessing the Flink web UI. For details, see "Note" in Creating a Cluster Connection.

Procedure

The following uses the process of interconnecting a Kafka mapping table to Hive as an example.

Create a cluster connection, for example, flink_hive.

Choose System Management > Cluster Connection Management. The Cluster Connection Management page is displayed.

Click Create Cluster Connection. On the displayed page, enter information by referring to Table 1 and click Test. After the test is successful, click OK.

**Table 1** Parameters for creating a cluster connection
Parameter	Description	Example Value
Cluster Connection Name	Name of the cluster connection, which can contain a maximum of 100 characters. Only letters, digits, and underscores (_) are allowed.	flink_hive
Description	Description of the cluster connection name.	-
Version	Select a cluster version.	MRS 3
Secure Version	If the secure version is used, select Yes for a security cluster. Enter the username and upload the user credential. If not, select No.	Yes
Username	The user must have the minimum permissions for accessing services in the cluster. The name can contain a maximum of 100 characters. Only letters, digits, and underscores (_) are allowed. This parameter is available only when Secure Version is set to Yes.	flink_admin
Client Profile	Client profile of the cluster, in TAR format.	-
User Credential	User authentication credential in FusionInsight Manager in TAR format. This parameter is available only when Secure Version is set to Yes. Files can be uploaded only after the username is entered.	User credential of flink_admin

Create a Flink SQL job, for example, flinktest1.

Click Job Management. The job management page is displayed.

Click Create Job. On the displayed job creation page, set parameters by referring to Table 2 and click OK. The job development page is displayed.

**Table 2** Parameters for creating a job
Parameter	Description	Example Value
Type	Job type, which can be Flink SQL or Flink Jar.	Flink SQL
Name	Job name, which can contain a maximum of 64 characters. Only letters, digits, and underscores (_) are allowed.	flinktest1
Task Type	Type of the job data source, which can be a stream job or a batch job.	Stream job
Description	Job description, which can contain a maximum of 100 characters.	-

On the job development page, enter the following statements and click Check Semantic to check the input content.

CREATE TABLE test_kafka (
  user_id varchar,
  item_id varchar,
  cat_id varchar,
  zw_test timestamp
) WITH (
  'properties.bootstrap.servers' = 'IP address of the Kafka broker instance:Kafka port number',
  'format' = 'json',
  'topic' = 'zw_tset_kafka',
  'connector' = 'kafka',
  'scan.startup.mode' = 'latest-offset',
  'properties.sasl.kerberos.service.name' = 'kafka',
  'properties.security.protocol' = 'SASL_PLAINTEXT',
  'properties.kerberos.domain.name' = 'hadoop.System domain name'

);
CREATE CATALOG myhive WITH (
  'type' = 'hive',
  'hive-version' = '3.1.0',
  'default-database' = 'default',
  'cluster.name' = 'flink_hive'
);
use catalog myhive;
set table.sql-dialect = hive;create table user_behavior_hive_tbl_no_partition (
    user_id STRING,
    item_id STRING,
    cat_id STRING,
    ts timestamp
  ) PARTITIONED BY (dy STRING, ho STRING, mi STRING) stored as textfile TBLPROPERTIES (
    'partition.time-extractor.timestamp-pattern' = '$dy $ho:$mi:00',
    'sink.partition-commit.trigger' = 'process-time',
    'sink.partition-commit.delay' = '0S',
    'sink.partition-commit.policy.kind' = 'metastore,success-file'
  );
INSERT into
  user_behavior_hive_tbl_no_partition
SELECT
  user_id,
  item_id,
  cat_id,
  zw_test,
  DATE_FORMAT(zw_test, 'yyyy-MM-dd'),
  DATE_FORMAT(zw_test, 'HH'),
  DATE_FORMAT(zw_test, 'mm')
FROM
  default_catalog.default_database.test_kafka;

Kafka port number
- In security mode, the port number is the value of sasl.port (21007 by default).
- In non-security mode, the port is the value of port (9092 by default). If the port number is set to 9092, set allow.everyone.if.no.acl.found to true. The procedure is as follows:
  Log in to FusionInsight Manager and choose Cluster > Services > Kafka. On the displayed page, click Configurations and then All Configurations, search for allow.everyone.if.no.acl.found, set its value to true, and click Save.
The value of 'cluster.name' is the name of the cluster connection created in 2.
For details about related parameters, visit Flink official website http://flink.apache.org/.

After the job is developed, select Enable CheckPoint in Running Parameter and set Time Interval (ms) to 60000.
Click Submit in the upper left corner to submit the job.
After the job is successfully executed, choose More > Job Monitoring to view the job running details.
Execute the following commands to view the topic and write data to Kafka. For details, see Managing Messages in Kafka Topics.

./kafka-topics.sh --list --zookeeper IP address of the ZooKeeper quorumpeer instance:ZooKeeper port number/kafka

sh kafka-console-producer.sh --broker-list IP address of the node where the Kafka instance locates:Kafka port number --topic Topic name --producer.config Client directory/Kafka/kafka/config/producer.properties

For example, if the topic name is zw_tset_kafka, the script is sh kafka-console-producer.sh --broker-list IP address of the node where the Kafka instance locates:Kafka port number --topic zw_tset_kafka --producer.config /opt/Bigdata/client/Kafka/kafka/config/producer.properties.
Enter the message content.
```
{"user_id": "3","item_id":"333333","cat_id":"cat333","zw_test":"2021-09-08 09:08:01"}
{"user_id": "4","item_id":"444444","cat_id":"cat444","zw_test":"2021-09-08 09:08:01"} 
```
Press Enter to send the message.
- IP address of the ZooKeeper quorumpeer instance
  To obtain IP addresses of all ZooKeeper quorumpeer instances, log in to FusionInsight Manager and choose Cluster > Services > ZooKeeper. On the displayed page, click Instance and view the IP addresses of all the hosts where the quorumpeer instances locate.
- Port number of the ZooKeeper client
  Log in to FusionInsight Manager and choose Cluster > Service > ZooKeeper. On the displayed page, click Configurations and check the value of clientPort. The default value is 24002.
Run the following command to check whether data is written from the Hive table to the sink table:

beeline

select * from user_behavior_hive_tbl_no_partition;