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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))
  }
})
```

return all([os.path.exists(f) for f in files])
    if target_file and not overwrite and os.path.exists(target_file):
        key_file_name = '%s.key' % target_file
        cert_file_name = '%s.crt' % target_file
        try:
            
            content = load_file(target_file)
            key_start = '-----BEGIN PRIVATE KEY-----'
            key_end = '-----END PRIVATE KEY-----'
            cert_start = '-----BEGIN CERTIFICATE-----'
            cert_end = '-----END CERTIFICATE-----'
            key_content = content[content.index(key_start): content.index(key_end) + len(key_end)]
            cert_content = content[content.index(cert_start): content.index(cert_end) + len(cert_end)]
            save_file(key_file_name, key_content)
            save_file(cert_file_name, cert_content)
        except Exception as e:
            LOG.info('Unable to store key/cert files for custom SSL certificate: %s' % e)
        if all_exist(key_file_name, cert_file_name):
            return target_file, cert_file_name, key_file_name
    if random and target_file:
        if '.' in target_file:
            target_file = target_file.replace('.', '.%s.' % short_uid(), 1)
        else:
            target_file = '%s.%s' % (target_file, short_uid())
    
    k = crypto.PKey()
    k.generate_key(crypto.TYPE_RSA, 2048)