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Alink

Alink is the Machine Learning algorithm platform based on Flink, developed by the PAI team of Alibaba computing platform. Welcome everyone to join the Alink open source user group to communicate.

List of Algorithms

PyAlink

Quick start

PyAlink Manual

Preparation before use:

About package names and versions:

• PyAlink provides different Python packages for Flink versions that Alink supports: package pyalink always maintains Alink Python API against the latest Flink version, which is 1.13, while pyalink-flink-*** support old-version Flink, which are pyalink-flink-1.12, pyalink-flink-1.11, pyalink-flink-1.10 and pyalink-flink-1.9 for now.
• The version of python packages always follows Alink Java version, like 1.6.2.

Installation steps:

1. Make sure the version of python3 on your computer is 3.6, 3.7 or 3.8.
2. Make sure Java 8 is installed on your computer.
3. Use pip to install: pip install pyalink, pip install pyalink-flink-1.12, pip install pyalink-flink-1.11, pip install pyalink-flink-1.10 or pip install pyalink-flink-1.9.

Potential issues:

1. pyalink and/or pyalink-flink-*** can not be installed at the same time. Multiple versions are not allowed. If pyalink or pyalink-flink-*** was/were installed, please use pip uninstall pyalink or pip uninstall pyalink-flink-*** to remove them.

2. If pip install is slow of failed, refer to this article to change the pip source, or use the following download links:

   • Flink 1.13：Link (MD5: d4b7b1fe6474b11ca7f45d0fb0daf5bc)
   • Flink 1.12：Link (MD5: 527b9ac24383ccc8593cd61b06cc610d)
   • Flink 1.11：Link (MD5: 7e59ba00b3739386996cf55d8f522ed2)
   • Flink 1.10：Link (MD5: 6d5d9048c9a44f27285467c5117e8deb)
   • Flink 1.9: Link (MD5: e89ac35a6a1c63c0426f3d9ca1025880)

3. If multiple version of Python exist, you may need to use a special version of pip, like pip3; If Anaconda is used, the command should be run in Anaconda prompt.

Download file system and Catalog dependency jar files:

After PyAlink installed, you can run download_pyalink_dep_jars to download dependency jars for file system and Hive. (If there is an error that could not find the command, you can run the python command python3 -c 'from pyalink.alink.download_pyalink_dep_jars import main;main()' directly.)

After executed the command, you'll see a prompt asking you about the dependencies and their versions to be downloaded. The following dependencies and their versions of jars are supported:

• OSS：3.4.1
• Hadoop：2.8.3
• Hive：2.3.4
• MySQL: 5.1.27
• Derby: 10.6.1.0
• SQLite: 3.19.3
• S3-hadoop: 1.11.788
• S3-presto: 1.11.788
• odps: 0.36.4-public

These jars will be installed to the lib/plugins folder of PyAlink. Note that these command require the access for the folder.

You can also add the argument -d when executing the command, i.e. download_pyalink_dep_jars -d. It will install all dependency jars.

Start using:

You can start using PyAlink with Jupyter Notebook to provide a better experience.

Steps for usage:

1. Start Jupyter: jupyter notebook in terminal , and create Python 3 notebook.

2. Import the pyalink package: from pyalink.alink import *.

3. Use this command to create a local runtime environment:

useLocalEnv(parallism, flinkHome=None, config=None).

Among them, the parameter parallism indicates the degree of parallelism used for execution;flinkHome is the full path of flink, and usually no need to set; config is the configuration parameter accepted by Flink. After running, the following output appears, indicating that the initialization of the running environment is successful. JVM listening on *** Python listening on *** 4. Start writing PyAlink code, for example: python source = CsvSourceBatchOp()\ .setSchemaStr("sepal_length double, sepal_width double, petal_length double, petal_width double, category string")\ .setFilePath("https://alink-release.oss-cn-beijing.aliyuncs.com/data-files/iris.csv") res = source.select(["sepal_length", "sepal_width"]) df = res.collectToDataframe() print(df)

Write code:

In PyAlink, the interface provided by the algorithm component is basically the same as the Java APIs, that is, an algorithm component is created through the default construction method, then the parameters are set through setXXX, and other components are connected through link / linkTo / linkFrom.

Here, Jupyter Notebook's auto-completion mechanism can be used to provide writing convenience.

For batch jobs, you can trigger execution through methods such as print / collectToDataframe / collectToDataframes of batch components or BatchOperator.execute (); for streaming jobs, start the job with StreamOperator.execute ().

More usage:

• Interchange between DataFrame and Operator
• StreamOperator data preview
• UDF/UDTF/SQL usage
• Use with PyFlink
• PyAlink Q&A

Java API Manual

KMeans Example

```java String URL = "https://alink-release.oss-cn-beijing.aliyuncs.com/data-files/iris.csv"; String SCHEMASTR = "sepallength double, sepalwidth double, petallength double, petal_width double, category string";

BatchOperator data = new CsvSourceBatchOp() .setFilePath(URL) .setSchemaStr(SCHEMA_STR);

VectorAssembler va = new VectorAssembler() .setSelectedCols(new String[]{"sepallength", "sepalwidth", "petallength", "petalwidth"}) .setOutputCol("features");

KMeans kMeans = new KMeans().setVectorCol("features").setK(3) .setPredictionCol("predictionresult") .setPredictionDetailCol("predictiondetail") .setReservedCols("category") .setMaxIter(100);

Pipeline pipeline = new Pipeline().add(va).add(kMeans); pipeline.fit(data).transform(data).print(); ```

With Flink-1.13

xml <dependency> <groupId>com.alibaba.alink</groupId> <artifactId>alink_core_flink-1.13_2.11</artifactId> <version>1.6.2</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-streaming-scala_2.11</artifactId> <version>1.13.0</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-table-planner_2.11</artifactId> <version>1.13.0</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-clients_2.11</artifactId> <version>1.13.0</version> </dependency>

With Flink-1.12

xml <dependency> <groupId>com.alibaba.alink</groupId> <artifactId>alink_core_flink-1.12_2.11</artifactId> <version>1.6.2</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-streaming-scala_2.11</artifactId> <version>1.12.1</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-table-planner_2.11</artifactId> <version>1.12.1</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-clients_2.11</artifactId> <version>1.12.1</version> </dependency>

With Flink-1.11

xml <dependency> <groupId>com.alibaba.alink</groupId> <artifactId>alink_core_flink-1.11_2.11</artifactId> <version>1.6.2</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-streaming-scala_2.11</artifactId> <version>1.11.0</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-table-planner_2.11</artifactId> <version>1.11.0</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-clients_2.11</artifactId> <version>1.11.0</version> </dependency>

With Flink-1.10

xml <dependency> <groupId>com.alibaba.alink</groupId> <artifactId>alink_core_flink-1.10_2.11</artifactId> <version>1.6.2</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-streaming-scala_2.11</artifactId> <version>1.10.0</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-table-planner_2.11</artifactId> <version>1.10.0</version> </dependency>

With Flink-1.9

xml <dependency> <groupId>com.alibaba.alink</groupId> <artifactId>alink_core_flink-1.9_2.11</artifactId> <version>1.6.2</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-streaming-scala_2.11</artifactId> <version>1.9.0</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-table-planner_2.11</artifactId> <version>1.9.0</version> </dependency>

Get started to run Alink Algorithm with a Flink Cluster

1. Prepare a Flink Cluster: shell wget https://archive.apache.org/dist/flink/flink-1.13.0/flink-1.13.0-bin-scala_2.11.tgz tar -xf flink-1.13.0-bin-scala_2.11.tgz && cd flink-1.13.0 ./bin/start-cluster.sh

2. Build Alink jar from the source: ```shell git clone https://github.com/alibaba/Alink.git

   add provided in pom.xml of alink_examples.

   cd Alink && mvn -Dmaven.test.skip=true clean package shade:shade ```

3. Run Java examples: ```shell ./bin/flink run -p 1 -c com.alibaba.alink.ALSExample [pathtoAlink]/examples/target/alink_examples-1.5-SNAPSHOT.jar

   ./bin/flink run -p 1 -c com.alibaba.alink.GBDTExample [pathtoAlink]/examples/target/alink_examples-1.5-SNAPSHOT.jar

   ./bin/flink run -p 1 -c com.alibaba.alink.KMeansExample [pathtoAlink]/examples/target/alink_examples-1.5-SNAPSHOT.jar

   ```

Deployment

Cluster