new test: retry policy

[Geal]

• we set up an application with two backends, but only one of the backend server is actually up
• the client does a serie of requests (no keep-alive)
• we check that sozu correctly reports one of the backend as down after a few requests

[NotBad4U]

Can you describe:

we check that sozu correctly reports one of the backend as down after a few requests
We got multiples HTTP 503 ?

[Geal]

two things to check:

• the client will receive a 503 response
• sozu's logs will show the message "no more available backends for application <app_id>"

[NotBad4U]

Done in 894c126

[Geal]

there's only one request there, so we're not sure it would try the backend that is down right away, and the test does not verify in sozu's logs that one of the backends was detected as down

[NotBad4U]

there's only one request there, so we're not sure it would try the backend that is down right away

Not really if we use a little trick like I did: I put the down backend in top of the backends list and use the roundrobin algorithm which has the effect of creating a connection attempt for this backend.

The test does not verify in sozu's logs that one of the backends was detected as down

Can I use this log https://github.com/sozu-proxy/sozu/blob/e0d026a4ac856057cd23e9c5c92f2b7b1f7d7d18/lib/src/network/http.rs#L506 ?

[Geal]

yes

[Geal]

it would probably be useful to have a test to detect the "no more available backends" message, but for this we would need to d requests in a loop until the message appears

[NotBad4U]

The problem is when we set up an application with two backends, but only one of the backend server is actually up, the log "no more available backends" is never logged but when we set up an application with only backend down (no backend up) then that work.