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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))
  }
})
```

if not port:
            if api in ['', None, '_unknown_']:
                truncated = truncate(data)
                LOG.info(('Unable to find forwarding rule for host "%s", path "%s", '
                    'target header "%s", auth header "%s", data "%s"') % (host, path, target, auth_header, truncated))
            else:
                LOG.info(('Unable to determine forwarding port for API "%s" - please '
                    'make sure this API is enabled via the SERVICES configuration') % api)
            response = Response()
            response.status_code = 404
            response._content = '{"status": "running"}'
            return response
        use_ssl = config.USE_SSL
        connect_host = '%s:%s' % (config.HOSTNAME, port)
        url = 'http%s://%s%s' % ('s' if use_ssl else '', connect_host, path)
        headers['Host'] = host
        function = getattr(requests, method.lower())
        if isinstance(data, dict):
            data = json.dumps(data)
        response = function(url, data=data, headers=headers, verify=False)
        return response
def get_api_from_headers(headers, path=None):
    """ Determine API and backend port based on Authorization headers. """
    target = headers.get('x-amz-target', '')
    host = headers.get('host', '')
    auth_header = headers.get('authorization', '')
    ls_target = headers.get(HEADER_LOCALSTACK_TARGET, '')
    path = path or '/'
    
    result = '_unknown_', 0