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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))
  }
})
```

@classmethod
    def setUpClass(cls):
        cls.dynamodb = aws_stack.connect_to_resource('dynamodb')
    def test_non_ascii_chars(self):
        aws_stack.create_dynamodb_table(TEST_DDB_TABLE_NAME, partition_key=PARTITION_KEY)
        table = self.dynamodb.Table(TEST_DDB_TABLE_NAME)
        
        items = {
            'id1': {PARTITION_KEY: 'id1', 'data': 'foobar123 ✓'},
            'id2': {PARTITION_KEY: 'id2', 'data': 'foobar123 £'},
            'id3': {PARTITION_KEY: 'id3', 'data': 'foobar123 ¢'}
        }
        for k, item in items.items():
            table.put_item(Item=item)
        for item_id in items.keys():
            item = table.get_item(Key={PARTITION_KEY: item_id})['Item']
            # ne
            item1 = json_safe(item)
            item2 = json_safe(items[item_id])
            self.assertEqual(item1, item2)
        # cl
        delete_table(TEST_DDB_TABLE_NAME)
    def test_large_data_download(self):