When running Flask and using SQLAlchemy to provide a mechanism to update a MariaDB database through Python code I came across a problem with the Fedora 26 implementation of MariaDB, the MySQL alternative that is packaged with Fedora.

It was while using Flask-Migrate to update the database I came across the following error:

$ flask db migrate
Traceback (most recent call last):
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.lots of errors
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return __import__('MySQLdb')
ImportError: No module named MySQLdb

No module named MySQLdb? I tried two things, firstly installing the mysql-python client package via pip:

$ pip install mysqlclient
Downloading mysqlclient-1.3.10.tar.gz (82kB)
  100% |████████████████████████████████| 92kB 2.9MB/s
Building wheels for collected packages: mysqlclient
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.
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gcc: error: /usr/lib/rpm/redhat/redhat-hardened-cc1: No such file or directory
error: command 'gcc' failed with exit status 1

No luck there, nasty compile error, so I tried to install the mysql-python package via DNF

$ sudo dnf install mysql-python
No package mysql-python available.
Error: Unable to find a match

No package available. I won’t go into the differences and split between MySQL and MariaDB, but this was starting to look like a compatibility issue. After lots of googling I found solutions for similar issues with Ubuntu, but nothing for Fedora.

Then I looked at the error further, the error for pip install mysqlclient was ending with gcc: error: /usr/lib/rpm/redhat/redhat-hardened-cc1: No such file or directory. Looking into that it seemed I needed the ‘redhat-rpm-config’ package, so:

sudo dnf install redhat-rpm-config

Once I had that installed, pip install mysqlclient worked a treat, and then flask db migrate worked as well!

As mentioned, this happened on Fedora26, I’m not sure if the same issue exists in earlier version of the Fed.