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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 msg:
        msg = 'The resource you requested does not exist.'
        if ref:
            msg = '%s not found: %s' % ('Function' if ':function:' in ref else 'Resource', ref)
    return error_response(msg, 404, error_type='ResourceNotFoundException')
@app.before_request
def before_request():
    
    transfer_encoding = request.headers.get('Transfer-Encoding', '').lower()
    if transfer_encoding == 'chunked':
        request.environ['wsgi.input_terminated'] = True
@app.route('%s/functions' % PATH_ROOT, methods=['POST'])
def create_function():
    """ Create new function
        ---
        operationId: 'createFunction'
        parameters:
            - name: 'request'
              in: body
    """
    arn = 'n/a'
    try:
        data = json.loads(to_str(request.data))
        lambda_name = data['FunctionName']
        event_publisher.fire_event(event_publisher.EVENT_LAMBDA_CREATE_FUNC,
            payload={'n': event_publisher.get_hash(lambda_name)})
        arn = func_arn(lambda_name)
        if arn in arn_to_lambda:
            return error_response('Function already exist: %s' %