[bitnami/mongodb] metrics exporter doesn't work with mTLS

[lasseoe]

Name and Version

bitnami/mongodb 16.4.5

What architecture are you using?

None

What steps will reproduce the bug?

Deploy mongodb with mTLS enabled and custom certificates.

Certificate extensions look like this, and incrementing the number for each pod:
DNS.1 = mongodb-headless
DNS.2 = mongodb-0
DNS.3 = mongodb-0.mongodb-headless.mongo-test.svc.cluster.local

Are you using any custom parameters or values?

architecture: replicaset
auth:
  enabled: true
  usernames:
    - "somedbuser"
  databases:
    - "somedb"
  existingSecret: "mongodb"
tls:
  enabled: true
  mTLS:
    enabled: true
  autoGenerated: false
  mode: requireTLS
  replicaset:
    existingSecrets:
      - mongodb-0-cert
      - mongodb-1-cert
      - mongodb-2-cert
metrics:
  enabled: true
  serviceMonitor:
    enabled: true

What is the expected behavior?

Metrics in Prometheus.

What do you see instead?

No metrics in Prometheus because mongodb_exporter connects to localhost instead of the actual pod hostname. Adding "localhost" to the certificates is not really an option.

time="2025-02-26T19:12:36Z" level=error msg="Cannot connect to MongoDB: cannot connect to MongoDB: server selection error: server selection timeout, current topology: { Type: Single, Servers: [{ Addr: localhost:27017, Type: Unknown, Last error: tls: failed to verify certificate: x509: certificate is valid for mongodb-headless, mongodb-0, mongodb-0.mongodb-headless, mongodb-0.mongodb-headless.mongo-test.svc.cluster.local, not localhost }, ] }"

Additional information

Everything else works just fine with our custom certificates

[carrodher]

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