

文档 AWS SDK 示例 GitHub 存储库中还有更多 [S AWS DK 示例](https://github.com/awsdocs/aws-doc-sdk-examples)。

本文属于机器翻译版本。若本译文内容与英语原文存在差异，则一律以英文原文为准。

# 与 AWS SDK `DiscoverInputSchema` 配合使用
<a name="kinesis-analytics-v2_example_kinesis-analytics-v2_DiscoverInputSchema_section"></a>

以下代码示例演示了如何使用 `DiscoverInputSchema`。

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#### [ Python ]

**适用于 Python 的 SDK（Boto3）**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/kinesis-analytics-v2#code-examples)中查找完整示例，了解如何进行设置和运行。

```
class KinesisAnalyticsApplicationV2:
    """Encapsulates Kinesis Data Analytics application functions."""

    def __init__(self, analytics_client):
        """
        :param analytics_client: A Boto3 Kinesis Data Analytics v2 client.
        """
        self.analytics_client = analytics_client
        self.name = None
        self.arn = None
        self.version_id = None
        self.create_timestamp = None


    def discover_input_schema(self, stream_arn, role_arn):
        """
        Discovers a schema that maps data in a stream to a format that is usable by
        an application's runtime environment. The stream must be active and have
        enough data moving through it for the service to sample. The returned schema
        can be used when you add the stream as an input to the application or you can
        write your own schema.

        :param stream_arn: The ARN of the stream to map.
        :param role_arn: A role that lets Kinesis Data Analytics read from the stream.
        :return: The discovered schema of the data in the input stream.
        """
        try:
            response = self.analytics_client.discover_input_schema(
                ResourceARN=stream_arn,
                ServiceExecutionRole=role_arn,
                InputStartingPositionConfiguration={"InputStartingPosition": "NOW"},
            )
            schema = response["InputSchema"]
            logger.info("Discovered input schema for stream %s.", stream_arn)
        except ClientError:
            logger.exception(
                "Couldn't discover input schema for stream %s.", stream_arn
            )
            raise
        else:
            return schema
```
+  有关 API 的详细信息，请参阅适用[DiscoverInputSchema](https://docs.aws.amazon.com/goto/boto3/kinesisanalyticsv2-2018-05-23/DiscoverInputSchema)于 *Python 的AWS SDK (Boto3) API 参考*。

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