schema_config renamed to schemaConfig and not documented

[slim-bean]

          Two issues so far with my existing Helm values:

loki.schema_config apparently became loki.schemaConfig. After renaming the object, that part was accepted (also by the 5.x helm chart).

Then the loki ConfigMap failed to be generated. The config.yaml value is literally Error: 'error converting YAML to JSON: yaml: line 70: mapping values are not allowed in this context'.

Trying to render the helm chart locally with "helm --debug template" results in

Error: template: loki/templates/write/statefulset-write.yaml:46:28: executing "loki/templates/write/statefulset-write.yaml" at <include (print .Template.BasePath "/config.yaml") .>: error calling include: template: loki/templates/config.yaml:19:7: executing "loki/templates/config.ya
ml" at <include "loki.calculatedConfig" .>: error calling include: template: loki/templates/_helpers.tpl:461:24: executing "loki.calculatedConfig" at <tpl .Values.loki.config .>: error calling tpl: error during tpl function execution for "
<<<< template removed for brevity >>>
": template: loki/templates/write/statefulset-write.yaml:37:6: executing "loki/templates/write/statefulset-write.yaml" at <include "loki.commonStorageConfig" .>: error calling include: template: loki/templates/_helpers.tpl:228:19: executing "loki.commonStorageConfig" at <$.Values.loki.storage.bucketNames.chunks>: nil pointer evaluating interface {}.chunks

I try to understand the nested template structure in the helm chart to understand what is happening.

A short helm chart values set (which worked fine with 5.x) triggering the phenomenon:

values.yaml

serviceAccount:
  create: false
  name: loki
test:
  enabled: false
monitoring:
  dashboards:
    enable: false
  lokiCanary:
    enabled: false
  selfMonitoring:
    enabled: false
    grafanaAgent:
      installOperator: false
loki:
  auth_enabled: false
  limits_config:
    max_streams_per_user: 10000
    max_global_streams_per_user: 10000
  storage_config:
    aws:
      s3: s3://eu-central-1
      bucketnames: my-bucket-name
  schemaConfig:
    configs:
      - from: 2024-01-19
        store: tsdb
        object_store: aws
        schema: v11
        index:
          prefix: "some-prefix_"
          period: 24h
  query_range:
    split_queries_by_interval: 0
  query_scheduler:
    max_outstanding_requests_per_tenant: 8192
  analytics:
    reporting_enabled: false
  compactor:
    shared_store: s3
gateway:
  replicas: 3
read:
  replicas: 3
write:
  replicas: 3
compactor:
  enable: true

Originally posted by @MartinEmrich in https://github.com/grafana/loki/issues/12506#issuecomment-2047231721