[BUG] 502 Proxy Error when uploading BOM

[reilly-callaway]

Describe the bug
502 Proxy Error when uploading BOM

Steps to Reproduce

1. Upload bill of materials button in part
2. Upload CSV BOM
3. Match appropriate fields
4. Press "Submit selections" on step 2 of 3
5. Hangs for a while
6. Server returns 502 Proxy error

Screenshots

Deployment Method

• Docker
• Bare Metal

Version Information
InvenTree-Version: 0.6.0 dev
Django Version: 3.2.5
Commit Hash: 77dac2e62
Commit Date: 2021-11-15
Database: mysql
Debug-Mode: True
Deployed using Docker: False

[SchrodingersGat]

For reference, this is due to the way that the 'BOM import' process provides options to the user.

For each line in the BOM template, the server has to render all available parts which could be selected, and then order them according to how well they match.

For a dataset with thousands of parts this takes a very long time!

This will require a pretty major rework (incoming) to fix...