

Sono disponibili altri esempi AWS SDK nel repository [AWS Doc SDK](https://github.com/awsdocs/aws-doc-sdk-examples) Examples. GitHub 

Le traduzioni sono generate tramite traduzione automatica. In caso di conflitto tra il contenuto di una traduzione e la versione originale in Inglese, quest'ultima prevarrà.

# Scenari di utilizzo CloudWatch AWS SDKs
<a name="cloudwatch_code_examples_scenarios"></a>

I seguenti esempi di codice mostrano come implementare scenari comuni in CloudWatch with AWS SDKs. Questi scenari mostrano come eseguire attività specifiche richiamando più funzioni all'interno CloudWatch o combinandole con altre Servizi AWS. Ogni scenario include un collegamento al codice sorgente completo, dove è possibile trovare le istruzioni su come configurare ed eseguire il codice. 

Gli scenari sono relativi a un livello intermedio di esperienza per aiutarti a comprendere le azioni di servizio nel contesto.

**Topics**
+ [Nozioni di base sugli allarmi](cloudwatch_example_cloudwatch_Scenario_GettingStarted_section.md)
+ [Gestione di parametri e allarmi](cloudwatch_example_cloudwatch_Usage_MetricsAlarms_section.md)
+ [Monitorare le prestazioni di DynamoDB](cloudwatch_example_cross_MonitorDynamoDB_section.md)

# Inizia a utilizzare gli CloudWatch allarmi utilizzando un SDK AWS
<a name="cloudwatch_example_cloudwatch_Scenario_GettingStarted_section"></a>

L’esempio di codice seguente mostra come:
+ Crea un allarme.
+ Disattivare le operazioni di allarme.
+ Descrivere un allarme.
+ Eliminare un allarme.

------
#### [ SAP ABAP ]

**SDK per SAP ABAP**  
 C'è altro da fare. GitHub Trova l'esempio completo e scopri di più sulla configurazione e l'esecuzione nel [Repository di esempi di codice AWS](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/sap-abap/services/cwt#code-examples). 

```
    DATA lt_alarmnames TYPE /aws1/cl_cwtalarmnames_w=>tt_alarmnames.
    DATA lo_alarmname TYPE REF TO /aws1/cl_cwtalarmnames_w.

    "Create an alarm"
    TRY.
        lo_cwt->putmetricalarm(
          iv_alarmname                 = iv_alarm_name
          iv_comparisonoperator        = iv_comparison_operator
          iv_evaluationperiods         = iv_evaluation_periods
          iv_metricname                = iv_metric_name
          iv_namespace                 = iv_namespace
          iv_statistic                 = iv_statistic
          iv_threshold                 = iv_threshold
          iv_actionsenabled            = iv_actions_enabled
          iv_alarmdescription          = iv_alarm_description
          iv_unit                      = iv_unit
          iv_period                    = iv_period
          it_dimensions                = it_dimensions ).
        MESSAGE 'Alarm created' TYPE 'I'.
      CATCH /aws1/cx_cwtlimitexceededfault.
        MESSAGE 'The request processing has exceeded the limit' TYPE 'E'.
    ENDTRY.

    "Create an ABAP internal table for the created alarm."
    lo_alarmname = NEW #( iv_value = iv_alarm_name ).
    INSERT lo_alarmname INTO TABLE lt_alarmnames.

    "Disable alarm actions."
    TRY.
        lo_cwt->disablealarmactions(
          it_alarmnames                = lt_alarmnames ).
        MESSAGE 'Alarm actions disabled' TYPE 'I'.
      CATCH /aws1/cx_rt_service_generic INTO DATA(lo_disablealarm_exception).
        DATA(lv_disablealarm_error) = |"{ lo_disablealarm_exception->av_err_code }" - { lo_disablealarm_exception->av_err_msg }|.
        MESSAGE lv_disablealarm_error TYPE 'E'.
    ENDTRY.

    "Describe alarm using the same ABAP internal table."
    TRY.
        oo_result = lo_cwt->describealarms(                       " oo_result is returned for testing purpose "
          it_alarmnames                = lt_alarmnames ).
        MESSAGE 'Alarms retrieved' TYPE 'I'.
      CATCH /aws1/cx_rt_service_generic INTO DATA(lo_describealarms_exception).
        DATA(lv_describealarms_error) = |"{ lo_describealarms_exception->av_err_code }" - { lo_describealarms_exception->av_err_msg }|.
        MESSAGE lv_describealarms_error TYPE 'E'.
    ENDTRY.

    "Delete alarm."
    TRY.
        lo_cwt->deletealarms(
          it_alarmnames = lt_alarmnames ).
        MESSAGE 'Alarms deleted' TYPE 'I'.
      CATCH /aws1/cx_cwtresourcenotfound.
        MESSAGE 'Resource being access is not found.' TYPE 'E'.
    ENDTRY.
```
+ Per informazioni dettagliate sull’API, consulta gli argomenti seguenti nella *documentazione di riferimento dell’API AWS SDK per SAP ABAP*.
  + [DeleteAlarms](https://docs.aws.amazon.com/sdk-for-sap-abap/v1/api/latest/index.html)
  + [DescribeAlarms](https://docs.aws.amazon.com/sdk-for-sap-abap/v1/api/latest/index.html)
  + [DisableAlarmActions](https://docs.aws.amazon.com/sdk-for-sap-abap/v1/api/latest/index.html)
  + [PutMetricAlarm](https://docs.aws.amazon.com/sdk-for-sap-abap/v1/api/latest/index.html)

------

# Gestisci CloudWatch metriche e allarmi utilizzando un SDK AWS
<a name="cloudwatch_example_cloudwatch_Usage_MetricsAlarms_section"></a>

L’esempio di codice seguente mostra come:
+ Crea una sveglia per monitorare una CloudWatch metrica.
+ Inserisci i dati in un parametro e attiva l’allarme.
+ Ottenere i dati dall’allarme.
+ Eliminare l’allarme.

------
#### [ Python ]

**SDK per Python (Boto3)**  
 C'è altro da fare. GitHub Trova l'esempio completo e scopri di più sulla configurazione e l'esecuzione nel [Repository di esempi di codice AWS](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/cloudwatch#code-examples). 
Crea una classe che racchiuda le operazioni. CloudWatch   

```
from datetime import datetime, timedelta
import logging
from pprint import pprint
import random
import time
import boto3
from botocore.exceptions import ClientError

logger = logging.getLogger(__name__)


class CloudWatchWrapper:
    """Encapsulates Amazon CloudWatch functions."""

    def __init__(self, cloudwatch_resource):
        """
        :param cloudwatch_resource: A Boto3 CloudWatch resource.
        """
        self.cloudwatch_resource = cloudwatch_resource


    def put_metric_data_set(self, namespace, name, timestamp, unit, data_set):
        """
        Sends a set of data to CloudWatch for a metric. All of the data in the set
        have the same timestamp and unit.

        :param namespace: The namespace of the metric.
        :param name: The name of the metric.
        :param timestamp: The UTC timestamp for the metric.
        :param unit: The unit of the metric.
        :param data_set: The set of data to send. This set is a dictionary that
                         contains a list of values and a list of corresponding counts.
                         The value and count lists must be the same length.
        """
        try:
            metric = self.cloudwatch_resource.Metric(namespace, name)
            metric.put_data(
                Namespace=namespace,
                MetricData=[
                    {
                        "MetricName": name,
                        "Timestamp": timestamp,
                        "Values": data_set["values"],
                        "Counts": data_set["counts"],
                        "Unit": unit,
                    }
                ],
            )
            logger.info("Put data set for metric %s.%s.", namespace, name)
        except ClientError:
            logger.exception("Couldn't put data set for metric %s.%s.", namespace, name)
            raise


    def create_metric_alarm(
        self,
        metric_namespace,
        metric_name,
        alarm_name,
        stat_type,
        period,
        eval_periods,
        threshold,
        comparison_op,
    ):
        """
        Creates an alarm that watches a metric.

        :param metric_namespace: The namespace of the metric.
        :param metric_name: The name of the metric.
        :param alarm_name: The name of the alarm.
        :param stat_type: The type of statistic the alarm watches.
        :param period: The period in which metric data are grouped to calculate
                       statistics.
        :param eval_periods: The number of periods that the metric must be over the
                             alarm threshold before the alarm is set into an alarmed
                             state.
        :param threshold: The threshold value to compare against the metric statistic.
        :param comparison_op: The comparison operation used to compare the threshold
                              against the metric.
        :return: The newly created alarm.
        """
        try:
            metric = self.cloudwatch_resource.Metric(metric_namespace, metric_name)
            alarm = metric.put_alarm(
                AlarmName=alarm_name,
                Statistic=stat_type,
                Period=period,
                EvaluationPeriods=eval_periods,
                Threshold=threshold,
                ComparisonOperator=comparison_op,
            )
            logger.info(
                "Added alarm %s to track metric %s.%s.",
                alarm_name,
                metric_namespace,
                metric_name,
            )
        except ClientError:
            logger.exception(
                "Couldn't add alarm %s to metric %s.%s",
                alarm_name,
                metric_namespace,
                metric_name,
            )
            raise
        else:
            return alarm


    def put_metric_data(self, namespace, name, value, unit):
        """
        Sends a single data value to CloudWatch for a metric. This metric is given
        a timestamp of the current UTC time.

        :param namespace: The namespace of the metric.
        :param name: The name of the metric.
        :param value: The value of the metric.
        :param unit: The unit of the metric.
        """
        try:
            metric = self.cloudwatch_resource.Metric(namespace, name)
            metric.put_data(
                Namespace=namespace,
                MetricData=[{"MetricName": name, "Value": value, "Unit": unit}],
            )
            logger.info("Put data for metric %s.%s", namespace, name)
        except ClientError:
            logger.exception("Couldn't put data for metric %s.%s", namespace, name)
            raise


    def get_metric_statistics(self, namespace, name, start, end, period, stat_types):
        """
        Gets statistics for a metric within a specified time span. Metrics are grouped
        into the specified period.

        :param namespace: The namespace of the metric.
        :param name: The name of the metric.
        :param start: The UTC start time of the time span to retrieve.
        :param end: The UTC end time of the time span to retrieve.
        :param period: The period, in seconds, in which to group metrics. The period
                       must match the granularity of the metric, which depends on
                       the metric's age. For example, metrics that are older than
                       three hours have a one-minute granularity, so the period must
                       be at least 60 and must be a multiple of 60.
        :param stat_types: The type of statistics to retrieve, such as average value
                           or maximum value.
        :return: The retrieved statistics for the metric.
        """
        try:
            metric = self.cloudwatch_resource.Metric(namespace, name)
            stats = metric.get_statistics(
                StartTime=start, EndTime=end, Period=period, Statistics=stat_types
            )
            logger.info(
                "Got %s statistics for %s.", len(stats["Datapoints"]), stats["Label"]
            )
        except ClientError:
            logger.exception("Couldn't get statistics for %s.%s.", namespace, name)
            raise
        else:
            return stats


    def get_metric_alarms(self, metric_namespace, metric_name):
        """
        Gets the alarms that are currently watching the specified metric.

        :param metric_namespace: The namespace of the metric.
        :param metric_name: The name of the metric.
        :returns: An iterator that yields the alarms.
        """
        metric = self.cloudwatch_resource.Metric(metric_namespace, metric_name)
        alarm_iter = metric.alarms.all()
        logger.info("Got alarms for metric %s.%s.", metric_namespace, metric_name)
        return alarm_iter


    def delete_metric_alarms(self, metric_namespace, metric_name):
        """
        Deletes all of the alarms that are currently watching the specified metric.

        :param metric_namespace: The namespace of the metric.
        :param metric_name: The name of the metric.
        """
        try:
            metric = self.cloudwatch_resource.Metric(metric_namespace, metric_name)
            metric.alarms.delete()
            logger.info(
                "Deleted alarms for metric %s.%s.", metric_namespace, metric_name
            )
        except ClientError:
            logger.exception(
                "Couldn't delete alarms for metric %s.%s.",
                metric_namespace,
                metric_name,
            )
            raise
```
Utilizza la classe wrapper per inserire i dati in un parametro, attivare un allarme che osserva il parametro e ottenere dati dall’allarme.  

```
def usage_demo():
    print("-" * 88)
    print("Welcome to the Amazon CloudWatch metrics and alarms demo!")
    print("-" * 88)

    logging.basicConfig(level=logging.INFO, format="%(levelname)s: %(message)s")

    cw_wrapper = CloudWatchWrapper(boto3.resource("cloudwatch"))

    minutes = 20
    metric_namespace = "doc-example-metric"
    metric_name = "page_views"
    start = datetime.utcnow() - timedelta(minutes=minutes)
    print(
        f"Putting data into metric {metric_namespace}.{metric_name} spanning the "
        f"last {minutes} minutes."
    )
    for offset in range(0, minutes):
        stamp = start + timedelta(minutes=offset)
        cw_wrapper.put_metric_data_set(
            metric_namespace,
            metric_name,
            stamp,
            "Count",
            {
                "values": [
                    random.randint(bound, bound * 2)
                    for bound in range(offset + 1, offset + 11)
                ],
                "counts": [random.randint(1, offset + 1) for _ in range(10)],
            },
        )

    alarm_name = "high_page_views"
    period = 60
    eval_periods = 2
    print(f"Creating alarm {alarm_name} for metric {metric_name}.")
    alarm = cw_wrapper.create_metric_alarm(
        metric_namespace,
        metric_name,
        alarm_name,
        "Maximum",
        period,
        eval_periods,
        100,
        "GreaterThanThreshold",
    )
    print(f"Alarm ARN is {alarm.alarm_arn}.")
    print(f"Current alarm state is: {alarm.state_value}.")

    print(
        f"Sending data to trigger the alarm. This requires data over the threshold "
        f"for {eval_periods} periods of {period} seconds each."
    )
    while alarm.state_value == "INSUFFICIENT_DATA":
        print("Sending data for the metric.")
        cw_wrapper.put_metric_data(
            metric_namespace, metric_name, random.randint(100, 200), "Count"
        )
        alarm.load()
        print(f"Current alarm state is: {alarm.state_value}.")
        if alarm.state_value == "INSUFFICIENT_DATA":
            print(f"Waiting for {period} seconds...")
            time.sleep(period)
        else:
            print("Wait for a minute for eventual consistency of metric data.")
            time.sleep(period)
            if alarm.state_value == "OK":
                alarm.load()
                print(f"Current alarm state is: {alarm.state_value}.")

    print(
        f"Getting data for metric {metric_namespace}.{metric_name} during timespan "
        f"of {start} to {datetime.utcnow()} (times are UTC)."
    )
    stats = cw_wrapper.get_metric_statistics(
        metric_namespace,
        metric_name,
        start,
        datetime.utcnow(),
        60,
        ["Average", "Minimum", "Maximum"],
    )
    print(
        f"Got {len(stats['Datapoints'])} data points for metric "
        f"{metric_namespace}.{metric_name}."
    )
    pprint(sorted(stats["Datapoints"], key=lambda x: x["Timestamp"]))

    print(f"Getting alarms for metric {metric_name}.")
    alarms = cw_wrapper.get_metric_alarms(metric_namespace, metric_name)
    for alarm in alarms:
        print(f"Alarm {alarm.name} is currently in state {alarm.state_value}.")

    print(f"Deleting alarms for metric {metric_name}.")
    cw_wrapper.delete_metric_alarms(metric_namespace, metric_name)

    print("Thanks for watching!")
    print("-" * 88)
```
+ Per informazioni dettagliate sull'API, consulta i seguenti argomenti nella *Documentazione di riferimento delle API SDK AWS per Python (Boto3)*.
  + [DeleteAlarms](https://docs.aws.amazon.com/goto/boto3/monitoring-2010-08-01/DeleteAlarms)
  + [DescribeAlarmsForMetric](https://docs.aws.amazon.com/goto/boto3/monitoring-2010-08-01/DescribeAlarmsForMetric)
  + [DisableAlarmActions](https://docs.aws.amazon.com/goto/boto3/monitoring-2010-08-01/DisableAlarmActions)
  + [EnableAlarmActions](https://docs.aws.amazon.com/goto/boto3/monitoring-2010-08-01/EnableAlarmActions)
  + [GetMetricStatistics](https://docs.aws.amazon.com/goto/boto3/monitoring-2010-08-01/GetMetricStatistics)
  + [ListMetrics](https://docs.aws.amazon.com/goto/boto3/monitoring-2010-08-01/ListMetrics)
  + [PutMetricAlarm](https://docs.aws.amazon.com/goto/boto3/monitoring-2010-08-01/PutMetricAlarm)
  + [PutMetricData](https://docs.aws.amazon.com/goto/boto3/monitoring-2010-08-01/PutMetricData)

------

# Monitora le prestazioni di Amazon DynamoDB utilizzando un SDK AWS
<a name="cloudwatch_example_cross_MonitorDynamoDB_section"></a>

L’esempio di codice seguente mostra come configurare l’utilizzo di DynamoDB da parte di un’applicazione per monitorare le prestazioni.

------
#### [ Java ]

**SDK per Java 2.x**  
 Questo esempio mostra come configurare un’applicazione Java per monitorare le prestazioni di DynamoDB. L'applicazione invia i dati metrici a CloudWatch cui è possibile monitorare le prestazioni.   
 Per il codice sorgente completo e le istruzioni su come configurarlo ed eseguirlo, guarda l'esempio completo su [GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/monitor_dynamodb).   

**Servizi utilizzati in questo esempio**
+ CloudWatch
+ DynamoDB

------