API returning 404 when attempting to create/update ACL policy with invalid rules

[gbolo]

Nomad version

Nomad v1.4.3 (f464aca721d222ae9c1f3df643b3c3aaa20e2da7)

Issue

when attempting to modify an ACL policy with invalid rules syntax, you will receive a 404 instead of a more appropriate status code like 400 or something.

Reproduction steps

create a an ACL policy, then retreive it to confirm it's presence:

http -v 127.0.0.1:4646/v1/acl/policy/gbolo-test 'X-Nomad-Token:<redacted>'
...
HTTP/1.1 200 OK
Content-Encoding: gzip
Content-Length: 489
Content-Type: application/json
Date: Tue, 31 Jan 2023 17:58:15 GMT
Vary: Accept-Encoding
X-Nomad-Index: 855
X-Nomad-Knownleader: true
X-Nomad-Lastcontact: 0

{
    "CreateIndex": 783,
    "Description": "testing2",
    "Hash": "QyBlyewLb7DAWDr4aZTy769phBId/afhyj7Y+gSVxQo=",
    "JobACL": null,
    "ModifyIndex": 855,
    "Name": "gbolo-test",
...

Then try to modify it with invalid rules:

http -v 127.0.0.1:4646/v1/acl/policy/gbolo-test Name=gbolo-test rules=bar 'X-Nomad-Token:<redacted>'

POST /v1/acl/policy/gbolo-test HTTP/1.1
...

{
    "Name": "gbolo-test",
    "rules": "invalid"
}


HTTP/1.1 404 Not Found
Content-Encoding: gzip
Content-Length: 150
Date: Tue, 31 Jan 2023 18:00:24 GMT
Vary: Accept-Encoding

policy 0 invalid: 1 error occurred:
	* failed to parse rules: Failed to parse ACL Policy: At 1:9: key 'invalid' expected start of object ('{') or assignment ('=')

Expected Result

Not sure if this was intentional or not, just opening an issue in case this was not the desired behaviour. I couldn't find any mention about the expected response in the documentation, its just completely missing.

Judging by the output, it looks like the server is aware that the client sent invalid input, so perhaps changing the status code won't be too difficult? Feel free to close this issue if this is the expected behaviour.

[gbolo]

pinging you @jrasell as perhaps you are already working close to this code in response to #15960

[jrasell]

Hi @gbolo and thanks for raising this. Yeah I am in that general area and this looks like a trivial fix, so I'll look into this.