# TestMetricFilter
<a name="API_TestMetricFilter"></a>

Tests the filter pattern of a metric filter against a sample of log event messages. You can use this operation to validate the correctness of a metric filter pattern.

## Request Syntax
<a name="API_TestMetricFilter_RequestSyntax"></a>

```
{
   "filterPattern": "string",
   "logEventMessages": [ "string" ]
}
```

## Request Parameters
<a name="API_TestMetricFilter_RequestParameters"></a>

For information about the parameters that are common to all actions, see [Common Parameters](CommonParameters.md).

The request accepts the following data in JSON format.

 ** [filterPattern](#API_TestMetricFilter_RequestSyntax) **   <a name="CWL-TestMetricFilter-request-filterPattern"></a>
A symbolic description of how CloudWatch Logs should interpret the data in each log event. For example, a log event can contain timestamps, IP addresses, strings, and so on. You use the filter pattern to specify what to look for in the log event message.  
Type: String  
Length Constraints: Minimum length of 0. Maximum length of 1024.  
Required: Yes

 ** [logEventMessages](#API_TestMetricFilter_RequestSyntax) **   <a name="CWL-TestMetricFilter-request-logEventMessages"></a>
The log event messages to test.  
Type: Array of strings  
Array Members: Minimum number of 1 item. Maximum number of 50 items.  
Length Constraints: Minimum length of 1.  
Required: Yes

## Response Syntax
<a name="API_TestMetricFilter_ResponseSyntax"></a>

```
{
   "matches": [ 
      { 
         "eventMessage": "string",
         "eventNumber": number,
         "extractedValues": { 
            "string" : "string" 
         }
      }
   ]
}
```

## Response Elements
<a name="API_TestMetricFilter_ResponseElements"></a>

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.

 ** [matches](#API_TestMetricFilter_ResponseSyntax) **   <a name="CWL-TestMetricFilter-response-matches"></a>
The matched events.  
Type: Array of [MetricFilterMatchRecord](API_MetricFilterMatchRecord.md) objects

## Errors
<a name="API_TestMetricFilter_Errors"></a>

For information about the errors that are common to all actions, see [Common Error Types](CommonErrors.md).

 ** InvalidParameterException **   
A parameter is specified incorrectly.  
HTTP Status Code: 400

 ** ServiceUnavailableException **   
The service cannot complete the request.  
HTTP Status Code: 500

## Examples
<a name="API_TestMetricFilter_Examples"></a>

### To test a metric filter pattern on Apache access.log events
<a name="API_TestMetricFilter_Example_1"></a>

The following example tests the specified metric filter pattern.

#### Sample Request
<a name="API_TestMetricFilter_Example_1_Request"></a>

```
POST / HTTP/1.1
Host: logs.<region>.<domain>
X-Amz-Date: <DATE>
Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=content-type;date;host;user-agent;x-amz-date;x-amz-target;x-amzn-requestid, Signature=<Signature>
User-Agent: <UserAgentString>
Accept: application/json
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Connection: Keep-Alive
X-Amz-Target: Logs_20140328.TestMetricFilter
{
  "filterPattern": "[ip, identity, user_id, timestamp, request, status_code, size]",
  "logEventMessages": [
    "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 1534",
    "127.0.0.1 - frank [10/Oct/2000:13:35:22 -0700] \"GET /apache_pb.gif HTTP/1.0\" 500 5324",
    "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 4355"
  ]
}
```

#### Sample Response
<a name="API_TestMetricFilter_Example_1_Response"></a>

```
HTTP/1.1 200 OK
x-amzn-RequestId: <RequestId>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Date: <Date>
{
  "matches": [
    {
      "eventNumber": 0,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 1534",
      "extractedValues": {
        "$status_code": "200",
        "$identity": "-",
        "$request": "GET /apache_pb.gif HTTP/1.0",
        "$size": "1534,",
        "$user_id": "frank",
        "$ip": "127.0.0.1",
        "$timestamp": "10/Oct/2000:13:25:15 -0700"
      }
    },
    {
      "eventNumber": 1,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:35:22 -0700] \"GET /apache_pb.gif HTTP/1.0\" 500 5324",
      "extractedValues": {
        "$status_code": "500",
        "$identity": "-",
        "$request": "GET /apache_pb.gif HTTP/1.0",
        "$size": "5324,",
        "$user_id": "frank",
        "$ip": "127.0.0.1",
        "$timestamp": "10/Oct/2000:13:35:22 -0700"
      }
    },
    {
      "eventNumber": 2,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 4355",
      "extractedValues": {
        "$status_code": "200",
        "$identity": "-",
        "$request": "GET /apache_pb.gif HTTP/1.0",
        "$size": "4355",
        "$user_id": "frank",
        "$ip": "127.0.0.1",
        "$timestamp": "10/Oct/2000:13:50:35 -0700"
      }
    }
  ]
}
```

### To test a metric filter pattern on Apache access.log events without specifying all the fields
<a name="API_TestMetricFilter_Example_2"></a>

The following example tests the specified metric filter pattern.

#### Sample Request
<a name="API_TestMetricFilter_Example_2_Request"></a>

```
POST / HTTP/1.1
Host: logs.<region>.<domain>
X-Amz-Date: <DATE>
Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=content-type;date;host;user-agent;x-amz-date;x-amz-target;x-amzn-requestid, Signature=<Signature>
User-Agent: <UserAgentString>
Accept: application/json
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Connection: Keep-Alive
X-Amz-Target: Logs_20140328.TestMetricFilter
{
  "filterPattern": "[..., size]",
  "logEventMessages": [
    "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 1534",
    "127.0.0.1 - frank [10/Oct/2000:13:35:22 -0700] \"GET /apache_pb.gif HTTP/1.0\" 500 5324",
    "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 4355"
  ]
}
```

#### Sample Response
<a name="API_TestMetricFilter_Example_2_Response"></a>

```
HTTP/1.1 200 OK
x-amzn-RequestId: <RequestId>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Date: <Date>
{
  "matches": [
    {
      "eventNumber": 0,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 1534",
      "extractedValues": {
        "$size": "1534",
        "$6": "200",
        "$4": "10/Oct/2000:13:25:15 -0700",
        "$5": "GET /apache_pb.gif HTTP/1.0",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    },
    {
      "eventNumber": 1,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:35:22 -0700] \"GET /apache_pb.gif HTTP/1.0\" 500 5324",
      "extractedValues": {
        "$size": "5324",
        "$6": "500",
        "$4": "10/Oct/2000:13:35:22 -0700",
        "$5": "GET /apache_pb.gif HTTP/1.0",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    },
    {
      "eventNumber": 2,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 4355",
      "extractedValues": {
        "$size": "4355",
        "$6": "200",
        "$4": "10/Oct/2000:13:50:35 -0700",
        "$5": "GET /apache_pb.gif HTTP/1.0",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    }
  ]
}
```

### To test a metric filter pattern on Apache access.log events without specifying any fields
<a name="API_TestMetricFilter_Example_3"></a>

The following example tests the specified metric filter pattern.

#### Sample Request
<a name="API_TestMetricFilter_Example_3_Request"></a>

```
POST / HTTP/1.1
Host: logs.<region>.<domain>
X-Amz-Date: <DATE>
Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=content-type;date;host;user-agent;x-amz-date;x-amz-target;x-amzn-requestid, Signature=<Signature>
User-Agent: <UserAgentString>
Accept: application/json
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Connection: Keep-Alive
X-Amz-Target: Logs_20140328.TestMetricFilter
{
  "filterPattern": "[]",
  "logEventMessages": [
    "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 1534",
    "127.0.0.1 - frank [10/Oct/2000:13:35:22 -0700] \"GET /apache_pb.gif HTTP/1.0\" 500 5324",
    "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 4355"
  ]
}
```

#### Sample Response
<a name="API_TestMetricFilter_Example_3_Response"></a>

```
HTTP/1.1 200 OK
x-amzn-RequestId: <RequestId>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Date: <Date>
{
  "matches": [
    {
      "eventNumber": 0,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 1534",
      "extractedValues": {
        "$7": "1534",
        "$6": "200",
        "$4": "10/Oct/2000:13:25:15 -0700",
        "$5": "GET /apache_pb.gif HTTP/1.0",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    },
    {
      "eventNumber": 1,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:35:22 -0700] \"GET /apache_pb.gif HTTP/1.0\" 500 5324",
      "extractedValues": {
        "$7": "5324",
        "$6": "500",
        "$4": "10/Oct/2000:13:35:22 -0700",
        "$5": "GET /apache_pb.gif HTTP/1.0",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    },
    {
      "eventNumber": 2,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 4355",
      "extractedValues": {
        "$7": "4355",
        "$6": "200",
        "$4": "10/Oct/2000:13:50:35 -0700",
        "$5": "GET /apache_pb.gif HTTP/1.0",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    }
  ]
}
```

### To test a metric filter pattern that matches successful requests in Apache access.log events
<a name="API_TestMetricFilter_Example_4"></a>

The following example tests the specified metric filter pattern.

#### Sample Request
<a name="API_TestMetricFilter_Example_4_Request"></a>

```
POST / HTTP/1.1
Host: logs.<region>.<domain>
X-Amz-Date: <DATE>
Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=content-type;date;host;user-agent;x-amz-date;x-amz-target;x-amzn-requestid, Signature=<Signature>
User-Agent: <UserAgentString>
Accept: application/json
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Connection: Keep-Alive
X-Amz-Target: Logs_20140328.TestMetricFilter
{
  "filterPattern": "[..., status_code=200, size]",
  "logEventMessages": [
    "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 1534",
    "127.0.0.1 - frank [10/Oct/2000:13:35:22 -0700] \"GET /apache_pb.gif HTTP/1.0\" 500 5324",
    "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 4355"
  ]
}
```

#### Sample Response
<a name="API_TestMetricFilter_Example_4_Response"></a>

```
HTTP/1.1 200 OK
x-amzn-RequestId: <RequestId>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Date: <Date>
{
  "matches": [
    {
      "eventNumber": 0,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 1534",
      "extractedValues": {
        "$status_code": "200",
        "$size": "1534",
        "$4": "10/Oct/2000:13:25:15 -0700",
        "$5": "GET /apache_pb.gif HTTP/1.0",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    },
    {
      "eventNumber": 2,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 200 4355",
      "extractedValues": {
        "$status_code": "200",
        "$size": "4355",
        "$4": "10/Oct/2000:13:50:35 -0700",
        "$5": "GET /apache_pb.gif HTTP/1.0",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    }
  ]
}
```

### To test a metric filter pattern that matches 4XX response codes for HTML pages in Apache access.log events
<a name="API_TestMetricFilter_Example_5"></a>

The following example tests the specified metric filter pattern.

#### Sample Request
<a name="API_TestMetricFilter_Example_5_Request"></a>

```
POST / HTTP/1.1
Host: logs.<region>.<domain>
X-Amz-Date: <DATE>
Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=content-type;date;host;user-agent;x-amz-date;x-amz-target;x-amzn-requestid, Signature=<Signature>
User-Agent: <UserAgentString>
Accept: application/json
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Connection: Keep-Alive
X-Amz-Target: Logs_20140328.TestMetricFilter
{
  "filterPattern": "[..., request=*.html*, status_code=4*,]",
  "logEventMessages": [
    "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /index.html HTTP/1.0\" 404 1534",
    "127.0.0.1 - frank [10/Oct/2000:13:35:22 -0700] \"GET /about-us/index.html HTTP/1.0\" 200 5324",
    "127.0.0.1 - frank [10/Oct/2000:13:50:35 -0700] \"GET /apache_pb.gif HTTP/1.0\" 404 4355",
    "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /products/index.html HTTP/1.0\" 400 1534",
  ]
}
```

#### Sample Response
<a name="API_TestMetricFilter_Example_5_Response"></a>

```
HTTP/1.1 200 OK
x-amzn-RequestId: <RequestId>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Date: <Date>
{
  "matches": [
    {
      "eventNumber": 0,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /index.html HTTP/1.0\" 404 1534",
      "extractedValues": {
        "$status_code": "404",
        "$request": "GET /index.html HTTP/1.0",
        "$7": "1534",
        "$4": "10/Oct/2000:13:25:15 -0700",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    },
    {
      "eventNumber": 3,
      "eventMessage": "127.0.0.1 - frank [10/Oct/2000:13:25:15 -0700] \"GET /products/index.html HTTP/1.0\" 400 1534",
      "extractedValues": {
        "$status_code": "400",
        "$request": "GET /products/index.html HTTP/1.0",
        "$7": "1534",
        "$4": "10/Oct/2000:13:25:15 -0700",
        "$2": "-",
        "$3": "frank",
        "$1": "127.0.0.1"
      }
    }
  ]
}
```

### To test a metric filter pattern that matches occurrences of "[ERROR]" in log events
<a name="API_TestMetricFilter_Example_6"></a>

The following example tests the specified metric filter pattern.

#### Sample Request
<a name="API_TestMetricFilter_Example_6_Request"></a>

```
POST / HTTP/1.1
Host: logs.<region>.<domain>
X-Amz-Date: <DATE>
Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=content-type;date;host;user-agent;x-amz-date;x-amz-target;x-amzn-requestid, Signature=<Signature>
User-Agent: <UserAgentString>
Accept: application/json
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Connection: Keep-Alive
X-Amz-Target: Logs_20140328.TestMetricFilter
{
  "filterPattern": "\"[ERROR]\"",
  "logEventMessages": [
    "02 May 2014 00:34:12,525 [INFO] Starting the application",
    "02 May 2014 00:35:14,245 [DEBUG] Database connection established",
    "02 May 2014 00:34:14,663 [INFO] Executing SQL Query",
    "02 May 2014 00:34:16,142 [ERROR] Unhanded exception: InvalidQueryException",
    "02 May 2014 00:34:16,224 [ERROR] Terminating the application"
  ]
}
```

#### Sample Response
<a name="API_TestMetricFilter_Example_6_Response"></a>

```
HTTP/1.1 200 OK
x-amzn-RequestId: <RequestId>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Date: <Date>
{
  "matches": [
    {
      "eventNumber": 3,
      "eventMessage": "02 May 2014 00:34:16,142 [ERROR] Unhanded exception: InvalidQueryException",
      "extractedValues": {}
    },
    {
      "eventNumber": 4,
      "eventMessage": "02 May 2014 00:34:16,224 [ERROR] Terminating the application",
      "extractedValues": {}
    }
  ]
}
```

### To test a metric filter pattern that matches occurrences of "[ERROR]" and "Exception" in log events
<a name="API_TestMetricFilter_Example_7"></a>

The following example tests the specified metric filter pattern.

#### Sample Request
<a name="API_TestMetricFilter_Example_7_Request"></a>

```
POST / HTTP/1.1
Host: logs.<region>.<domain>
X-Amz-Date: <DATE>
Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=content-type;date;host;user-agent;x-amz-date;x-amz-target;x-amzn-requestid, Signature=<Signature>
User-Agent: <UserAgentString>
Accept: application/json
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Connection: Keep-Alive
X-Amz-Target: Logs_20140328.TestMetricFilter
{
  "filterPattern": "\"[ERROR]\" Exception",
  "logEventMessages": [
    "02 May 2014 00:34:12,525 [INFO] Starting the application",
    "02 May 2014 00:35:14,245 [DEBUG] Database connection established",
    "02 May 2014 00:34:14,663 [INFO] Executing SQL Query",
    "02 May 2014 00:34:16,142 [ERROR] Unhanded exception: InvalidQueryException",
    "02 May 2014 00:34:16,224 [ERROR] Terminating the application"
  ]
}
```

#### Sample Response
<a name="API_TestMetricFilter_Example_7_Response"></a>

```
HTTP/1.1 200 OK
x-amzn-RequestId: <RequestId>
Content-Type: application/x-amz-json-1.1
Content-Length: <PayloadSizeBytes>
Date: <Date>
{
  "matches": [
    {
      "eventNumber": 3,
      "eventMessage": "02 May 2014 00:34:16,142 [ERROR] Unhanded exception: InvalidQueryException",
      "extractedValues": {}
    }
  ]
}
```

## See Also
<a name="API_TestMetricFilter_SeeAlso"></a>

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS Command Line Interface V2](https://docs.aws.amazon.com/goto/cli2/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/logs-2014-03-28/TestMetricFilter) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/logs-2014-03-28/TestMetricFilter)