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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))
  }
})
```

}
        aws_stack.create_dynamodb_table(table_name, partition_key='id')
        dynamodb.put_item(TableName=table_name, Item=item)
        return ''
    if re.match(r'^https?://.+', config.LAMBDA_FALLBACK_URL):
        headers = {'lambda-function-name': lambda_name}
        response = safe_requests.post(config.LAMBDA_FALLBACK_URL, data, headers=headers)
        return response.content
    raise ClientError('Unexpected value for LAMBDA_FALLBACK_URL: %s' % config.LAMBDA_FALLBACK_URL)
def get_lambda_policy(function):
    iam_client = aws_stack.connect_to_service('iam')
    policies = iam_client.list_policies(Scope='Local', MaxItems=500)['Policies']
    docs = []
    for p in policies:
        
        versions = iam_client.list_policy_versions(PolicyArn=p['Arn'])['Versions']
        default_version = [v for v in versions if v.get('IsDefaultVersion')]
        versions = default_version or versions
        doc = versions[0]['Document']
        doc = doc if isinstance(doc, dict) else json.loads(doc)
        if not isinstance(doc['Statement'], list):
            doc['Statement'] = [doc['Statement']]
        for stmt in doc['Statement']:
            stmt['Principal'] = stmt.get('Principal') or {'AWS': TEST_AWS_ACCOUNT_ID}
        doc['PolicyArn'] = p['Arn']
        doc['Id'] = 'default'
        docs.append(doc)
    policy = [d for d in docs if d['Statement'][0]['Resource'] == func_arn(function)]
    return (policy or [None])[0]
def not_found_error(ref=None, msg=None):