Flink 客户端操作命令及可视化工具

Flink 客户端操作命令及可视化工具

flink提供了丰富的客户端操作来提交任务和与任务进行交互。下面主要从Flink命令行、Scala ShellSQL ClientRestful APIWeb五个方面进行整理。

Flink安装目录的bin目录下可以看到flinkstart-scala-shell.shsql-client.sh等文件,这些都是客户端操作的入口。

flink 常见操作:可以通过 -help 查看帮助

run 运行任务

-d:以分离模式运行作业
-c:如果没有在jar包中指定入口类,则需要在这里通过这个参数指定;
-m:指定需要连接的jobmanager(主节点)地址,使用这个参数可以指定一个不同于配置文件中的jobmanager,可以说是yarn集群名称;
-p:指定程序的并行度。可以覆盖配置文件中的默认值;
-s:保存点savepoint的路径以还原作业来自(例如hdfs:///flink/savepoint-1537);

[root@hadoop1 flink-1.10.1]# bin/flink run -d examples/streaming/TopSpeedWindowing.jar 
Executing TopSpeedWindowing example with default input data set.
Use --input to specify file input.
Printing result to stdout. Use --output to specify output path.
Job has been submitted with JobID dce7b69ad15e8756766967c46122736f

就可以看到我们提交的JobManager,默认是一个并发。

点进去就可以看到详细的信息

点击左侧TaskManager —Stdout能看到具体输出的日志信息。

或者查看TaskManager节点的log目录下的*.out文件,也能看到具体的输出信息。

list 查看任务列表

-mjobmanager<arg>作业管理器(主)的地址连接。

[root@hadoop1 flink-1.10.1]# bin/flink list -m 127.0.0.1:8081
Waiting for response...
------------------ Running/Restarting Jobs -------------------
09.07.2020 16:44:09 : dce7b69ad15e8756766967c46122736f : CarTopSpeedWindowingExample (RUNNING)
--------------------------------------------------------------
No scheduled jobs.

Stop 停止任务

需要指定jobmanagerip:protjobId。如下报错可知,一个job能够被stop要求所有的source都是可以stoppable的,即实现了 StoppableFunction接口。

[root@hadoop1 flink-1.10.1]# bin/flink stop -m 127.0.0.1:8081 dce7b69ad15e8756766967c46122736f
Suspending job "dce7b69ad15e8756766967c46122736f" with a savepoint.

------------------------------------------------------------
 The program finished with the following exception:

org.apache.flink.util.FlinkException: Could not stop with a savepoint job "dce7b69ad15e8756766967c46122736f".
    at org.apache.flink.client.cli.CliFrontend.lambda$stop$5(CliFrontend.java:458)

StoppableFunction接口如下,属于优雅停止任务。

 /**
 * @Description 需要 stoppabel 的函数必须实现此接口,例如流式任务 source*
 *               stop() 方法在任务收到 stop信号的时候调用
 *               source 在接收到这个信号后,必须停止发送新的数据优雅的停止。
 * @Date 2020/7/9 17:26
 */
 @PublicEvolving
 public interface StoppableFunction {
     /**
     * 停止 source,与 cancel() 不同的是,这是一个让 source优雅停止的请求。
     * 等待中的数据可以继续发送出去,不需要立即停止
    */
    void stop();
}

Cancel 取消任务

如果在conf/flink-conf.yaml里面配置state.savepoints.dir,会保存savepoint,否则不会保存savepoint。(重启)

state.savepoints.dir: file:///tmp/savepoint

执行 Cancel命令 取消任务

[root@hadoop1 flink-1.10.1]# bin/flink cancel -m 127.0.0.1:8081 -s e8ce0d111262c52bf8228d5722742d47
DEPRECATION WARNING: Cancelling a job with savepoint is deprecated. Use "stop" instead.
Cancelling job e8ce0d111262c52bf8228d5722742d47 with savepoint to default savepoint directory.
Cancelled job e8ce0d111262c52bf8228d5722742d47. Savepoint stored in file:/tmp/savepoint/savepoint-e8ce0d-f7fa96a085d8.

也可以在停止的时候显示指定savepoint目录

1 [root@hadoop1 flink-1.10.1]# bin/flink cancel -m 127.0.0.1:8081 -s /tmp/savepoint f58bb4c49ee5580ab5f27fdb24083353
DEPRECATION WARNING: Cancelling a job with savepoint is deprecated. Use "stop" instead.
Cancelling job f58bb4c49ee5580ab5f27fdb24083353 with savepoint to /tmp/savepoint.
Cancelled job f58bb4c49ee5580ab5f27fdb24083353. Savepoint stored in file:/tmp/savepoint/savepoint-f58bb4-127b7e84910e.

取消和停止(流作业)的区别如下:
cancel()调用, 立即调用作业算子的cancel()方法,以尽快取消它们。如果算子在接到cancel()调用后没有停止,Flink将开始定期中断算子线程的执行,直到所有算子停止为止。
stop()调用 ,是更优雅的停止正在运行流作业的方式。stop()仅适用于source实现了StoppableFunction接口的作业。当用户请求停止作业时,作业的所有source都将接收stop()方法调用。直到所有source正常关闭时,作业才会正常结束。这种方式,使 作业正常处理完所有作业。

触发 savepoint

当需要生成savepoint文件时,需要手动触发savepoint。如下,需要指定正在运行的 JobID 和生成文件的存放目录。同时,我们也可以看到它会返回给用户存放的savepoint的文件名称等信息。

 [root@hadoop1 flink-1.10.1]# bin/flink run -d examples/streaming/TopSpeedWindowing.jar 
 Executing TopSpeedWindowing example with default input data set.
 Use --input to specify file input.
 Printing result to stdout. Use --output to specify output path.
 Job has been submitted with JobID 216c427d63e3754eb757d2***268a448d
 [root@hadoop1 flink-1.10.1]# bin/flink savepoint -m 127.0.0.1:8081 216c427d63e3754eb757d2***268a448d /tmp/savepoint/
 Triggering savepoint for job 216c427d63e3754eb757d2***268a448d.
 Waiting for response...
 Savepoint ***pleted. Path: file:/tmp/savepoint/savepoint-216c42-154a34cf6bfd
 You can resume your program from this savepoint with the run ***mand.

savepointcheckpoint的区别:
checkpoint是增量做的,每次的时间较短,数据量较小,只要在程序里面启用后会自动触发,用户无须感知;savepoint是全量做的,每次的时间较长,数据量较大,需要用户主动去触发。
checkpoint是作业failover的时候自动使用,不需要用户指定。savepoint一般用于程序的版本更新,bug修复,A/B Test等场景,需要用户指定。

从指定 savepoint 中启动

[root@hadoop1 flink-1.10.1]# bin/flink run -d -s /tmp/savepoint/savepoint-f58bb4-127b7e84910e/ examples/streaming/TopSpeedWindowing.jar 
Executing TopSpeedWindowing example with default input data set.
Use --input to specify file input.
Printing result to stdout. Use --output to specify output path.
Job has been submitted with JobID 1a5c5ce279e0e4bd8609f541b37652e2

查看JobManager的日志能够看到Reset the checkpoint ID为我们指定的savepoint文件中的ID

modify 修改任务并行度

这里修改masterconf/flink-conf.yamltask slot数修改为4。并通过xsync分发到 两个slave节点上。

taskmanager.numberOfTaskSlots: 4

修改参数后需要重启集群生效:关闭/启动集群

[root@hadoop1 flink-1.10.1]# bin/stop-cluster.sh && bin/start-cluster.sh 
Stopping taskexecutor daemon (pid: 8236) on host hadoop2.
Stopping taskexecutor daemon (pid: 8141) on host hadoop3.
Stopping standalonesession daemon (pid: 22633) on host hadoop1.
Starting cluster.
Starting standalonesession daemon on host hadoop1.
Starting taskexecutor daemon on host hadoop2.
Starting taskexecutor daemon on host hadoop3.

启动任务

[root@hadoop1 flink-1.10.1]# bin/flink run -d examples/streaming/TopSpeedWindowing.jar 
Executing TopSpeedWindowing example with default input data set.
Use --input to specify file input.
Printing result to stdout. Use --output to specify output path.
Job has been submitted with JobID 2e833a438da7d8052f14d5433910515a

从页面上能看到Task Slots总计变为了8,运行的Slot1,剩余Slot数量为7

这时候默认的并行度是1

Flink1.0版本命令行flink modify已经没有这个行为了,被移除了。。。Flink1.7上是可以运行的。

[root@hadoop1 flink-1.10.1]# bin/flink modify -p 4 ***22***3d09f5d65651d637be6fb0a1c3
"modify" is not a valid action.

Info 显示程序的执行计划

[root@hadoop1 flink-1.10.1]# bin/flink info examples/streaming/TopSpeedWindowing.jar 
----------------------- Execution Plan -----------------------
{"nodes":[{"id":1,"type":"Source: Custom Source","pact":"Data Source","contents":"Source: Custom Source","parallelism":1},{"id":2,"type":"Timestamps/Watermarks","pact":"Operator","contents":"Timestamps/Watermarks","parallelism":1,"predecessors":[{"id":1,"ship_strategy":"FORWARD","side":"second"}]},{"id":4,"type":"Window(GlobalWindows(), DeltaTrigger, TimeEvictor, ***parableAggregator, PassThroughWindowFunction)","pact":"Operator","contents":"Window(GlobalWindows(), DeltaTrigger, TimeEvictor, ***parableAggregator, PassThroughWindowFunction)","parallelism":1,"predecessors":[{"id":2,"ship_strategy":"HASH","side":"second"}]},{"id":5,"type":"Sink: Print to Std. Out","pact":"Data Sink","contents":"Sink: Print to Std. Out","parallelism":1,"predecessors":[{"id":4,"ship_strategy":"FORWARD","side":"second"}]}]}
--------------------------------------------------------------

拷贝输出的json内容,粘贴到这个网站:http://flink.apache.org/visualizer/可以生成类似如下的执行图。

可以与实际运行的物理执行计划进行对比。

SQL Client Beta

进入 Flink SQL

[root@hadoop1 flink-1.10.1]# bin/sql-client.sh embedded

Select查询,按Q退出如下界面;

Flink SQL> select 'hello word';
                                                                                                        SQL Query Result (Table)
 Table program finished.                                                                                       Page: Last of 1                                                                                         Updated: 16:37:04.649

                    EXPR$0
                hello word




Q Quit                                         + Inc Refresh                                  G Goto Page                                    N Next Page                                    O Open Row
R Refresh                                      - Dec Refresh                                  L Last Page                                    P Prev Page

打开http://hadoop1:8081能看到这条select语句产生的查询任务已经结束了。这个查询采用的是读取固定数据集的Custom Source,输出用的是Stream Collect Sink,且只输出一条结果。

explain 查看 SQL 的执行计划。

Flink SQL> explain SELECT name, COUNT(*) AS ***t FROM (VALUES ('Bob'), ('Alice'), ('Greg'), ('Bob')) AS NameTable(name) GROUP BY name;
== Abstract Syntax Tree ==         //抽象语法树
LogicalAggregate(group=[{0}], ***t=[COUNT()])
+- LogicalValues(type=[RecordType(VARCHAR(5) name)], tuples=[[{ _UTF-16LE'Bob' }, { _UTF-16LE'Alice' }, { _UTF-16LE'Greg' }, { _UTF-16LE'Bob' }]])

== Optimized Logical Plan ==      //优化后的逻辑执行计划
GroupAggregate(groupBy=[name], select=[name, COUNT(*) AS ***t])
+- Exchange(distribution=[hash[name]])
   +- Values(type=[RecordType(VARCHAR(5) name)], tuples=[[{ _UTF-16LE'Bob' }, { _UTF-16LE'Alice' }, { _UTF-16LE'Greg' }, { _UTF-16LE'Bob' }]])

== Physical Execution Plan ==    //物理执行计划
Stage 13 : Data Source
    content : Source: Values(tuples=[[{ _UTF-16LE'Bob' }, { _UTF-16LE'Alice' }, { _UTF-16LE'Greg' }, { _UTF-16LE'Bob' }]])

    Stage 15 : Operator
        content : GroupAggregate(groupBy=[name], select=[name, COUNT(*) AS ***t])
        ship_strategy : HASH

结果展示

SQL Client支持两种模式来维护并展示查询结果:

table mode

在内存中物化查询结果,并以分页table形式展示。用户可以通过以下命令启用table mode:例如如下案例;

Flink SQL> SET execution.result-mode=table;
[INFO] Session property has been set.

Flink SQL>  SELECT name, COUNT(*) AS ***t FROM (VALUES ('Bob'), ('Alice'), ('Greg'), ('Bob')) AS NameTable(name) GROUP BY name;
                                                                                                          SQL Query Result (Table)
 Table program finished.                                                                                       Page: Last of 1                                                                                         Updated: 16:55:08.589

                      name                       ***t
                     Alice                         1
                      Greg                         1
                       Bob                         2



Q Quit                                         + Inc Refresh                                  G Goto Page                                    N Next Page                                    O Open Row
R Refresh                                      - Dec Refresh                                  L Last Page                                    P Prev Page

changelog mode

不会物化查询结果,而是直接对continuous query产生的添加和撤回retractions结果进行展示:如下案例中的-表示撤回消息

Flink SQL> SET execution.result-mode=changelog;
[INFO] Session property has been set.

Flink SQL>  SELECT name, COUNT(*) AS ***t FROM (VALUES ('Bob'), ('Alice'), ('Greg'), ('Bob')) AS NameTable(name) GROUP BY name;
                                                                                                        SQL Query Result (Changelog)
 Table program finished.                                                                                                                                                                                               Updated: 16:58:05.777

 +/-                      name                       ***t
   +                       Bob                         1
   +                     Alice                         1
   +                      Greg                         1
   -                       Bob                         1
   +                       Bob                         2



Q Quit                                                                        + Inc Refresh                                                                 O Open Row
R Refresh                                                                     - Dec Refresh

Environment Files

CREATE TABLE 创建表DDL语句:

Flink SQL> CREATE TABLE pvuv_sink (
>     dt VARCHAR,
>     pv BIGINT,
>     uv BIGINT
> ) ;
[INFO] Table has been created.

SHOW TABLES 查看所有表名

Flink SQL>  show tables;
pvuv_sink

DESCRIBE 表名 查看表的详细信息;

Flink SQL>  describe pvuv_sink;
root
 |-- dt: STRING
 |-- pv: BIGINT
 |-- uv: BIGINT

插入等操作均与关系型数据库操作语句一样,省略N个操作

Restful API

接下来我们演示如何通过rest api来提交jar包和执行任务。

通过Show Plan可以看到执行图

提交之后的操作,取消的话点击页面的Cancel Job

转载请说明出处内容投诉
CSS教程_站长资源网 » Flink 客户端操作命令及可视化工具

发表评论

欢迎 访客 发表评论

一个令你着迷的主题!

查看演示 官网购买