Adding headers to requests for Alertmanager provider.

[d4rkfella]

Hello, i've been trying to create alertmanager provider using oauth as an authentication method. What i did was create a docker image that runs a script to obtain an access token then create a secret with the obtained token like this .

#!/bin/bash

TOKEN=$(curl -X POST "$KEYCLOAK_URL" \
  -d "client_id=$CLIENT_ID" \
  -d "client_secret=$CLIENT_SECRET" \
  -d "grant_type=client_credentials" \
  -d "scope=$SCOPE" \
  -H "Content-Type: application/x-www-form-urlencoded" | jq -r .access_token)

echo -e "apiVersion: v1
kind: Secret
metadata:
  name: oidc-jwt
stringData:
  headers: |
    Authorization: Bearer $TOKEN" | kubectl apply -f -

I've manually tested the token with curl and i can authenticate no problem, but when the notification controller tries to send an alert it not adding the header i have specified in the referenced secret. Is it currently possible to add headers to the requests for an Alertmanager provider ?

[matheuscscp]

The Provider API already supports the specification of a token inside a secret:

https://fluxcd.io/flux/components/notification/providers/#token-example

But the alertmanager provider does not use it. We could modify the constructor of this provider to accept a token like opsgenie:

notification-controller/internal/notifier/opsgenie.go

Lines 43 to 57 in fa7d9f2

	func NewOpsgenie(hookURL string, proxyURL string, certPool *x509.CertPool, token string) (*Opsgenie, error) {
	_, err := url.ParseRequestURI(hookURL)
	if err != nil {
	return nil, fmt.Errorf("invalid Opsgenie hook URL %s: '%w'", hookURL, err)
	}
	if token == "" {
	return nil, errors.New("empty Opsgenie apikey/token")
	}
	return &Opsgenie{
	URL: hookURL,
	ProxyURL: proxyURL,
	CertPool: certPool,
	ApiKey: token,

And, if the token is not empty, use it more or less like this:

notification-controller/internal/notifier/opsgenie.go

Lines 81 to 83 in fa7d9f2

	err := postMessage(ctx, s.URL, s.ProxyURL, s.CertPool, payload, func(req *retryablehttp.Request) {
	req.Header.Set("Authorization", "GenieKey "+s.ApiKey)
	})

It's an easy implementation. @d4rkfella are you willing to contribute this feature?

[d4rkfella]

I could give it a shot . Looks easy enough for me :P

[d4rkfella]

Opened a pull request , let me know if i did it correctly.