pyflink, ImportError: No module named pyflink

Question

I am testing pyflink on

• os: centos7
• flink version: flink-1.14.3
• virtualenv python version: Python 3.6.8

pip list:

• apache-beam 2.27.0
• apache-flink 1.14.3
• apache-flink-libraries 1.14.3
• avro-python3 1.9.2.1
• certifi 2021.10.8
• charset-normalizer 2.0.11
• cloudpickle 1.2.2
• crcmod 1.7
• dill 0.3.1.1
• docopt 0.6.2
• fastavro 0.23.6
• future 0.18.2
• grpcio 1.43.0
• hdfs 2.6.0
• httplib2 0.17.4
• idna 3.3
• mock 2.0.0
• numpy 1.19.5
• oauth2client 4.1.3
• pandas 1.1.5
• pbr 5.8.1
• pip 21.3.1
• protobuf 3.17.3
• py4j 0.10.8.1
• pyarrow 2.0.0
• pyasn1 0.4.8
• pyasn1-modules 0.2.8
• pydot 1.4.2
• pyflink 1.0
• pymongo 3.12.3
• pyparsing 3.0.7
• python-dateutil 2.8.0
• pytz 2021.3
• requests 2.27.1
• rsa 4.8
• setuptools 59.6.0
• six 1.16.0
• typing-extensions 3.7.4.3
• urllib3 1.26.8
• wheel 0.37.1

I tried to run this command :

• (virtualenv) [myuser@myvm flink-1.14.3] ./bin/flink run -py examples/python/table/word_count.py And got the following error:

Caused by: java.io.IOException: Failed to execute the command: python -c import pyflink;import os;print(os.path.join(os.path.abspath(os.path.dirname(pyflink.file)), 'bin')) output: Traceback (most recent call last): File "", line 1, in ImportError: No module named pyflink

I am sure pyflink package is already installed. Does anyone know why?

Answer 1

You have to check if pyflink is well installed (in your venv)

also check if you are running Flink

if no, start it with :

start-cluster.sh

here is full documentation about PyFlink: https://nightlies.apache.org/flink/flink-docs-master/docs/dev/python/overview/

Answer 2

To install PyFlink, you only need to execute:

python -m pip install apache-flink

and make sure you have a compatible Python version (>= 3.5).

The problem may be the Python Virtual Environment， refer to https://nightlies.apache.org/flink/flink-docs-release-1.14/docs/dev/python/faq/#preparing-python-virtual-environment

Also may be you can add option '-pyexec venv.zip/venv/bin/python3' and have a try