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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))
  }
})
```

m = hashlib.md5()
    m.update(to_bytes(string))
    return m.hexdigest()
def in_docker():
    return config.in_docker()
def has_docker():
    try:
        run('docker ps')
        return True
    except Exception:
        return False
def get_docker_container_names():
    return bootstrap.get_docker_container_names()
def is_port_open(port_or_url, http_path=None, expect_success=True, protocols=['tcp']):
    port = port_or_url
    host = 'localhost'
    protocol = 'http'
    protocols = protocols if isinstance(protocols, list) else [protocols]
    if isinstance(port, six.string_types):
        url = urlparse(port_or_url)
        port = url.port
        host = url.hostname
        protocol = url.scheme
    nw_protocols = []
    nw_protocols += ([socket.SOCK_STREAM] if 'tcp' in protocols else [])
    nw_protocols += ([socket.SOCK_DGRAM] if 'udp' in protocols else [])
    for nw_protocol in nw_protocols:
        with closing(socket.socket(socket.AF_INET, nw_protocol)) as sock:
            sock.settimeout(1)
            if nw_protocol == socket.SOCK_DGRAM: