CloudWatch Logs Insights

Question

How to convert a string value to a number in the CloudWatch Logs Insights query.

My Object

```
{
            "readonly": false,
            "value": "30",
            "key": "MeterValueSampleInterval"
        }
```

![CloudWatch Logs Insights query](/media/postImages/original/IM81f4sZzaRv2CU5CQGGTx9Q)

Answer

If you're logging a JSON object, CWL should parse it automatically out of the message for you (you'll see `key`, `readonly` and `value` show in the "Discovered Fields" panel on the right). You can just specify the fields in the `fields` keyword.

The [documentation](https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/CWL_QuerySyntax-operations-functions.html#CWL_QuerySyntax-operations-comparison) says that the comparison operators work on any datatype so there's no need to convert your string value to an int explicity (the error you're getting is because you're using a `to_int()` function which doesn't exist.

For example, I injected your sample message in to a log stream and I can find it with this query:

```
fields @timestamp, @message, value
| filter value = 30
```

![Query demo](/media/postImages/original/IMy0wtVgPKTDi18BQ8MSYVlA)

CloudWatch Logs Insights

相關內容