Support UUID param on PXE endpoint

[bastelfreak]

we would like to pass an additional param to the pxe endpoint, a UUID. This will later be used from the installimage to interact with APIs. You can currently pass it, but it gets ignored:

root@dhcp01 ~ # curl -u admin:secret --data 'ip_address=10.30.7.41&label=archrescue&uuid=345455645645456' http://dhcp01de:8080/v1/pxe
{
    "ip_address": "10.30.7.41",
    "label": "archrescue",
    "password": "Qs4o5XwHVYcn_8AY",
    "script": null
}
root@dhcp01 ~ # cat /srv/tftp/pxelinux.cfg/0A1E0729 
INCLUDE pxelinux.cfg/default
DEFAULT instantboot
PROMPT 0
TIMEOUT 1
LABEL instantboot
    KERNEL cmd.c32
    APPEND archrescue HASH=$6$TzG382c1PO9ogCT1$pO9rMFtWSCoxv9xRrBTsmsiunr5HJcufp8nSWHMrquetZ5g29FJ4sqnJbo7rTmaUKh7b5TA9wKDIlII5.Y3o21
root@dhcp01 ~ #

[bastelfreak]

because I'm old and forgetting stufff: we need this in the pxe endpoint, not installimage. this allows us to implement a keep-alive script in the livesystem which we can use if a booted system still does something. This will be very funny if we ever run root on NFS setups and the NFS dies for a short (or longer ime)...

[bastelfreak]

How do we want to deal with malformend UUIDs that we get? recreate a new one or don't accept the data at all and return a bad http status code?

[bastelfreak]

Another funny thing, do we care about duplicate UUIDs?

[pbyatshon]

I think we should create a UUID for every PXE config, that would help us to track every installation status. If none supplied, create a UUID4, if invalid UUID create one as well.

Concerning duplicate UUIDs, thats a good question, depends on further intended use. Generating a duplicate UUID is highly unlikely, such situation might only occur when testing with fixed values. With a database backend we could easily lookup for dupes, otherwise we would have to scan each configuration file, which wouldn't be so nice. If we wanna care for dupes, the POST might result in a 409.

[bastelfreak]

I would like to keep the plain files, I think we can ignore the case of two duplicate UUIDs. What about returning 409 on a malformend UUID that we got?

[sebastianrakel]

We could use the uuid as filename, so you don't have to scan every file

[bastelfreak]

Sounds great

[bastelfreak]

implemented