Installing Python 3.8 on CentOS 7 for Hue

You must install Python 3.8 on all hosts on which you want to run the Hue service after installing Cloudera Manager and before adding the services to your cluster.

If you are using Oracle Enterprise Linux (OEL) 7, CentOS 7, RHEL 7, then you must install Python 3.8 and then install the psycopg2-binary package for using PostgreSQL as a backend database for Hue.

Install the necessary developer tools such as gcc and make on your system.

Install the following packages before installing Python 3.8:

openssl-devel
bzip2-devel
libffi-devel
zlib-devel

yum install gcc openssl-devel bzip2-devel libffi-devel zlib-devel -y

SSH into the host system as a root user.
Change directory to /opt:
```
cd /opt
```

Download Python 3.8 as follows:

curl -O https://www.python.org/ftp/python/3.8.12/Python-3.8.12.tgz

Decompress the package as follows:
```
tar -zxvf Python-3.8.12.tgz
```
Install Python 3.8 as follows:
```
./configure --enable-shared
```
The --enabled-shared option is used to build a shared library instead of a static library.
Build Python 3.8 as follows:
1. Run the make command to compile the files:
```
make
```
2. Run the following command to put the compiled files in the default location or in the custom location that you specified using the --prefix option:
```
make install
```
3. Copy the shared compiled library files (libpython3.8.so) to the /lib64/ directory:
```
cp --no-clobber ./libpython3.8.so* /lib64/
```
  The --no-clobber option is used to prevent overwriting files.
4. Change the permissions of the libpython3.8.so files as follows:
```
chmod 755 /lib64/libpython3.8.so*
```
If you see an error such as error while loading shared libraries: libpython3.8.so.1.0: cannot open shared object file: No such file or directory, then run the following commands:
```
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib/
echo $PATH
```
Change the permission of the Python 3.8 installation directory to 755 so that Hue and its related services can leverage the binary and the site packages, as follows:
```
chmod -R 755 /usr/local/lib/python3.8
```

(For Hue) If you have installed Python 3.8 at a custom location, then you must append the custom path in Cloudera Manager > Clusters > Hue > Configuration > Hue Service Environment Advanced Configuration Snippet (Safety Valve) separated by colon (:) as follows:

Key: PATH

Value: [***CUSTOM-INSTALL-PATH***]:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin