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# Type of request: This is a ...

[x ] bug report
[ ] feature request

# Detailed description

Not able to use the edge service to write metric data to cloudwatch via the javascript aws-sdk.

However, It **DOES** work when using the deprecated cloudwatch port.

## Expected behavior

Metric data to be visible when calling `awslocal cloudwatch list-metrics`

## Actual behavior

404 from edge service. No metric data is persisted, localstack instance logs the following info:

```
INFO:localstack.services.edge: Unable to determine forwarding port for API "monitoring" - please make sure this API is enabled via the SERVICES configuration
```

# Steps to reproduce

Run JS code in "Client code" section.
See 404 Error

## Command used to start LocalStack

`TMPDIR=/tmp/localstack docker-compose up`

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)

```js
const AWS = require('aws-sdk')
const cw = new AWS.CloudWatch({
  endpoint: 'http://localhost:4566',
})

const data = {
  Namespace: 'ns',
  MetricData: [
    {
      MetricName: 'metric-name',
      Timestamp: new Date(),
      Value: 12345,
      Unit: 'Milliseconds',
      Dimensions: [
        { Name: 'Environment', Value: 'local' },
      ]
    }
  ]
}

cw.putMetricData(data, (err, data) => {
  if (err) {
      console.log('Error', err)
  } else {
      console.log('Success', JSON.stringify(data))
  }
})
```

)
                        messages = result.get('Messages')
                        if not messages:
                            continue
                        send_event_to_lambda(queue_arn, queue_url, lambda_arn, messages, region=region_name)
                    except Exception as e:
                        LOG.debug('Unable to poll SQS messages for queue %s: %s' % (queue_arn, e))
            except Exception:
                pass
            finally:
                time.sleep(SQS_POLL_INTERVAL_SEC)
    LOG.debug('Starting SQS message polling thread for Lambda API')
    SQS_LISTENER_THREAD['_thread_'] = FuncThread(listener_loop)
    SQS_LISTENER_THREAD['_thread_'].start()
def process_sqs_message(queue_name, region_name=None):
    
    try:
        region_name = region_name or aws_stack.get_region()
        queue_arn = aws_stack.sqs_queue_arn(queue_name, region_name=region_name)
        sources = get_event_sources(source_arn=queue_arn)
        arns = [s.get('FunctionArn') for s in sources]
        LOG.debug('Found %s source mappings for event from SQS queue %s: %s' % (len(arns), queue_arn, arns))
        source = (sources or [None])[0]
        if not source:
            return False
        start_lambda_sqs_listener()
        return True
    except Exception as e:
        LOG.warning('Unable to run Lambda function on SQS messages: %s %s' % (e, traceback.format_exc()))
def get_event_sources(func_name=None, source_arn=None):