[![locals {
  metric_filter_name    = "ResolverErrorMetricFilter"
  metric_name           = "ResolverErrorMetric"
  metric_namespace      = "CustomAppsyncMetric"
  metric_filter_pattern = "{($.graphQLAPIId = "${aws_appsync_graphql_api.my_api.id}") && ($.logType = "ResponseFunctionEvaluation") && ($.fieldInError IS TRUE)}"
}

resource "aws_cloudwatch_log_metric_filter" "appsync_custom_metric" {
  name           = local.metric_name
  pattern        = local.metric_filter_pattern
  log_group_name = aws_cloudwatch_log_group.logs-Appsync.name

  metric_transformation {
    name      = local.metric_name
    namespace = local.metric_namespace
    value     = 1
    unit      = "Count"
    dimensions = {
      GraphQLAPIId = "$.graphQLAPIId"
      LogType = "$.logType"
    }
  }

  depends_on = [aws_cloudwatch_log_group.logs-Appsync]
}][1]][1]

This configuration is not working . Unable to see the dimensions in aws.
https://github.com/hashicorp/terraform-provider-aws/issues/19608