Circular reference is generated in `/node_modules`

ghost commented 4 years ago

At what date and time did you most recently experience the problem? -> The time when App Service on Linux (Node.js blessed image) starts more than 3 times
Where did you experience the problem? E.g. Azure Web Apps, Azure Functions, Azure Container Registry, or offline use. -> I think that it happens on only App Service on Linux (Node.js blessed image), because the issue is caused by /opt/startup/startup.sh for Node.js application.
If your repo is publicly available please share its URL: -> This issue can be reproduced by simple node.js application.
What happened? -> A symlink which links to /node_modules is generated in the directory itself, i.e. the symlink is circular reference, /node_modules/node_modules -> /node_modules

This causes unexpected behavior on applications which follow all symlink. e.g. Angular application which is set preserveSymlink to true.

And this causes Maximum call stack size exceeded error on executing npm ls.

What did you expect or want to happen? -> Any circular reference was never generated.
How can we reproduce it? -> It can be reproduced by repeating following steps 3 times at least.
1. Start any Node.js application on App Service on Linux
2. Access to the application by web browser for executing /opt/start/startup.sh
3. Stop the application.
Do you have log output? Please include between the backticks: -> Though there is no log, a reproduce process is found. This is caused by mv command in /opt/startup/startup.sh which is generated by oryx.
1. At first starting, symlink /home/site/wwwroot/node_modules is generated by ln at this in the script. Then /home/site/wwwroot/node_modules links to /node_modules.
2. At second starting, the symlink is moved to /home/site/wwwroot/_del_node_modules by /home/site/wwwroot/node_modules using mv at this. Then it is succeeded and /home/site/wwwroot/_del_node_modules which links to /node_modules is generated.
3. At third starting, the script tries to overwrite /home/site/wwwroot/_del_node_modules by /home/site/wwwroot/node_modules using the mv again. But the mv doesn't overwrite for symlink to directories, it moves /home/site/wwwroot/node_modules into /home/site/wwwroot/_del_node_modules (i.e. /node_nodules).

As a result, /node_modules includes the symlink which links to itself.

A current workaround is to execute following command in a script specified as startup command

unlink /node_modules/node_modules &>/dev/null

Could you please look into this?

Regards,

arroyc commented 4 years ago

@hihorika Thank you for reporting in detail, we will try to repro it and if possible a fix at our earliest.

ghost commented 4 years ago

Hi @arroyc Could you repro this behavior? Please let me know if you cannot repro this.

arroyc commented 4 years ago

@hihorika can't repro this .. lets chat over teams and show me if you can still repro this

ghost commented 4 years ago

We shared repro steps. Thanks @arroyc

arroyc commented 4 years ago

@hihorika just waiting for ant-88 deployments, once that completes hopefully this issue will be resolved. Tagging it as tracking for now.

arroyc commented 4 years ago

should be available in the coming deployment of ant-88 ..

microsoft / Oryx