chekos' today i learned

how to solve permission error from airflow official docker image

what i learned

tl;dr: when you use the Airflow official docker image you need to make sure that the variable AIRFLOW_UID is set to match your UID (and AIRFLOW_GID=0 aka root ) or you’re going to get permission errors. i was working on deploying Airflow on a VM at work this week and I got a permission error (Errno 13) regarding the containers’ python’s logging config. When I first started working with this docker-compose.yml i used the suggested echo -e "AIRFLOW_UID=$(id -u)" > .env command which provided my user id (let’s say it’s 506 ) from my local machine and assigned it to the AIRFLOW_UID key. Now that i am working in the VM and have extended my .env file to include other information i figured i could just use a copy of the same file. Everything else works fine except airflow cannot write logs because the user in this virtual machine with user id 506 does not have permission to write to this ./logs/ directory. If you google this error i found — among a sea of almost right answers — that most of the solutions online are variations of “change the logs folder’s permissions to 777” meaning anyone can read, write, and execute the contents of the logs. That works. However, you don’t really need everyone to be able to read and write — just this airflow user. Updating the UID on the VM’s .env file worked perfectly without having to mess with the permissions.

how i learned

i kept getting permissions errors so i changed the ./logs/ directories permissions to 777 and ran docker-compose up airflow-init . Now that airflow was able to write logs i could run ls -l logs/ and see that the owner of these logs was some user with id 506 which i recognized from the .env file. From there all i had to do was run id -u to find the correct user id (the id of the user i’m logged in as in this VM) and update the .env file to match.

reference

the airflow documentation → airflow.apache.org/docs/apache-airflow/stable/start/docker.html

this stackoverflow answer → stackoverflow.com/questions/67698656/cant-init-db-for-airflow-docker-compose-permission-denied/67704988

this fantastic explanation of user and groups permissions → unix.stackexchange.com/questions/116070/granting-write-permissions-to-a-group-to-a-folder

#docker #airflow #python