Allow both YAML string and objects to get passed in for OTEL config.

[jefchien]

Issue #, if available: N/A

Description of changes: With the current implementation, the otelConfig expects a YAML object in the values.yaml

  otelConfig:
    receivers:
      otlp/custom-suffix:
        protocols:
          http:
    exporters:
      awscloudwatchlogs/custom-suffix:
        log_group_name: "test-group"
        log_stream_name: "test-stream"
    service:
      pipelines:
        logs/from-values:
          receivers: [ otlp/custom-suffix ]
          exporters: [ awscloudwatchlogs/custom-suffix ]

but does not work for YAML strings (e.g. when passing in the value using --set agent.otelConfig).

Error: UPGRADE FAILED: template: amazon-cloudwatch-observability/templates/linux/cloudwatch-agent-custom-resource.yaml:84:17: executing "amazon-cloudwatch-observability/templates/linux/cloudwatch-agent-custom-resource.yaml" at <include "cloudwatch-agent.modify-yaml-config" (merge (dict "OtelConfig" $agent.otelConfig) .)>: error calling include: template: amazon-cloudwatch-observability/templates/_helpers.tpl:52:31: executing "cloudwatch-agent.modify-yaml-config" at <$configCopy>: range can't iterate over 

With the change, the helm chart can now accept either a YAML object or string, which means the values.yaml can take an object and --set agent.otelConfig can be used to pass in a string.

helm upgrade --install --namespace amazon-cloudwatch amazon-cloudwatch-observability ./charts/amazon-cloudwatch-observability/ --create-namespace --set region=$REGION --set clusterName=$CLUSTER_NAME --set agent.otelConfig='
  receivers:
    otlp/custom-suffix:
      protocols:
        http:
  exporters:
    awscloudwatchlogs/custom-suffix:
      log_group_name: "test-group"
      log_stream_name: "test-stream"
  service:
    pipelines:
      logs/on-set:
        receivers: [otlp/custom-suffix]
        exporters: [awscloudwatchlogs/custom-suffix]                                                                                                                                                           
Release "amazon-cloudwatch-observability" has been upgraded. Happy Helming!
NAME: amazon-cloudwatch-observability
LAST DEPLOYED: Fri Jan 24 11:08:44 2025
NAMESPACE: amazon-cloudwatch
STATUS: deployed
REVISION: 37
TEST SUITE: None

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[musa-asad]

This was simplified, was this verified to change the ConfigMap properly?

[jefchien]

Yeah it works.

--set agent.otelConfig='
  extensions:
    health_check/custom-suffix:
  receivers:
    otlp/custom-suffix:
      protocols:
        http:
  processors:
    batch/custom-suffix:
  exporters:
    awscloudwatchlogs/custom-suffix:
      log_group_name: "test-group"
      log_stream_name: "test-stream"
  service:
    extensions: [health_check/custom-suffix]
    pipelines:
      logs/custom-suffix:
        receivers: [otlp/custom-suffix]
        processors: [batch/custom-suffix]
        exporters: [awscloudwatchlogs/custom-suffix]
'

becomes

cwagentotelconfig.yaml:
----
exporters:
  awscloudwatchlogs/custom-suffix:
    log_group_name: test-group
    log_stream_name: test-stream
extensions:
  health_check/custom-suffix: {}
processors:
  batch/custom-suffix: {}
receivers:
  otlp/custom-suffix:
    protocols:
      http: null
service:
  extensions:
  - health_check/custom-suffix
  pipelines:
    logs/custom-suffix:
      exporters:
      - awscloudwatchlogs/custom-suffix
      processors:
      - batch/custom-suffix
      receivers:
      - otlp/custom-suffix