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。

# 使用 SDK for Python (Boto3) 的 Amazon Textract 示例
<a name="python_3_textract_code_examples"></a>

以下代码示例向您展示了如何在 Amazon Textract 中 适用于 Python (Boto3) 的 AWS SDK 使用来执行操作和实现常见场景。

*操作*是大型程序的代码摘录，必须在上下文中运行。您可以通过操作了解如何调用单个服务函数，还可以通过函数相关场景的上下文查看操作。

*场景*是向您演示如何通过在一个服务中调用多个函数或与其他 AWS 服务结合来完成特定任务的代码示例。

每个示例都包含一个指向完整源代码的链接，您可以从中找到有关如何在上下文中设置和运行代码的说明。

**Topics**
+ [操作](#actions)
+ [场景](#scenarios)

## 操作
<a name="actions"></a>

### `AnalyzeDocument`
<a name="textract_AnalyzeDocument_python_3_topic"></a>

以下代码示例演示了如何使用 `AnalyzeDocument`。

**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/textract#code-examples)中查找完整示例，了解如何进行设置和运行。

```
class TextractWrapper:
    """Encapsulates Textract functions."""

    def __init__(self, textract_client, s3_resource, sqs_resource):
        """
        :param textract_client: A Boto3 Textract client.
        :param s3_resource: A Boto3 Amazon S3 resource.
        :param sqs_resource: A Boto3 Amazon SQS resource.
        """
        self.textract_client = textract_client
        self.s3_resource = s3_resource
        self.sqs_resource = sqs_resource


    def analyze_file(
        self, feature_types, *, document_file_name=None, document_bytes=None
    ):
        """
        Detects text and additional elements, such as forms or tables, in a local image
        file or from in-memory byte data.
        The image must be in PNG or JPG format.

        :param feature_types: The types of additional document features to detect.
        :param document_file_name: The name of a document image file.
        :param document_bytes: In-memory byte data of a document image.
        :return: The response from Amazon Textract, including a list of blocks
                 that describe elements detected in the image.
        """
        if document_file_name is not None:
            with open(document_file_name, "rb") as document_file:
                document_bytes = document_file.read()
        try:
            response = self.textract_client.analyze_document(
                Document={"Bytes": document_bytes}, FeatureTypes=feature_types
            )
            logger.info("Detected %s blocks.", len(response["Blocks"]))
        except ClientError:
            logger.exception("Couldn't detect text.")
            raise
        else:
            return response
```
+  有关 API 的详细信息，请参阅适用[AnalyzeDocument](https://docs.aws.amazon.com/goto/boto3/textract-2018-06-27/AnalyzeDocument)于 *Python 的AWS SDK (Boto3) API 参考*。

### `DetectDocumentText`
<a name="textract_DetectDocumentText_python_3_topic"></a>

以下代码示例演示了如何使用 `DetectDocumentText`。

**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/textract#code-examples)中查找完整示例，了解如何进行设置和运行。

```
class TextractWrapper:
    """Encapsulates Textract functions."""

    def __init__(self, textract_client, s3_resource, sqs_resource):
        """
        :param textract_client: A Boto3 Textract client.
        :param s3_resource: A Boto3 Amazon S3 resource.
        :param sqs_resource: A Boto3 Amazon SQS resource.
        """
        self.textract_client = textract_client
        self.s3_resource = s3_resource
        self.sqs_resource = sqs_resource


    def detect_file_text(self, *, document_file_name=None, document_bytes=None):
        """
        Detects text elements in a local image file or from in-memory byte data.
        The image must be in PNG or JPG format.

        :param document_file_name: The name of a document image file.
        :param document_bytes: In-memory byte data of a document image.
        :return: The response from Amazon Textract, including a list of blocks
                 that describe elements detected in the image.
        """
        if document_file_name is not None:
            with open(document_file_name, "rb") as document_file:
                document_bytes = document_file.read()
        try:
            response = self.textract_client.detect_document_text(
                Document={"Bytes": document_bytes}
            )
            logger.info("Detected %s blocks.", len(response["Blocks"]))
        except ClientError:
            logger.exception("Couldn't detect text.")
            raise
        else:
            return response
```
+  有关 API 的详细信息，请参阅适用[DetectDocumentText](https://docs.aws.amazon.com/goto/boto3/textract-2018-06-27/DetectDocumentText)于 *Python 的AWS SDK (Boto3) API 参考*。

### `GetDocumentAnalysis`
<a name="textract_GetDocumentAnalysis_python_3_topic"></a>

以下代码示例演示了如何使用 `GetDocumentAnalysis`。

**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/textract#code-examples)中查找完整示例，了解如何进行设置和运行。

```
class TextractWrapper:
    """Encapsulates Textract functions."""

    def __init__(self, textract_client, s3_resource, sqs_resource):
        """
        :param textract_client: A Boto3 Textract client.
        :param s3_resource: A Boto3 Amazon S3 resource.
        :param sqs_resource: A Boto3 Amazon SQS resource.
        """
        self.textract_client = textract_client
        self.s3_resource = s3_resource
        self.sqs_resource = sqs_resource


    def get_analysis_job(self, job_id):
        """
        Gets data for a previously started detection job that includes additional
        elements.

        :param job_id: The ID of the job to retrieve.
        :return: The job data, including a list of blocks that describe elements
                 detected in the image.
        """
        try:
            response = self.textract_client.get_document_analysis(JobId=job_id)
            job_status = response["JobStatus"]
            logger.info("Job %s status is %s.", job_id, job_status)
        except ClientError:
            logger.exception("Couldn't get data for job %s.", job_id)
            raise
        else:
            return response
```
+  有关 API 的详细信息，请参阅适用[GetDocumentAnalysis](https://docs.aws.amazon.com/goto/boto3/textract-2018-06-27/GetDocumentAnalysis)于 *Python 的AWS SDK (Boto3) API 参考*。

### `StartDocumentAnalysis`
<a name="textract_StartDocumentAnalysis_python_3_topic"></a>

以下代码示例演示了如何使用 `StartDocumentAnalysis`。

**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/textract#code-examples)中查找完整示例，了解如何进行设置和运行。
启动异步任务以分析文档。  

```
class TextractWrapper:
    """Encapsulates Textract functions."""

    def __init__(self, textract_client, s3_resource, sqs_resource):
        """
        :param textract_client: A Boto3 Textract client.
        :param s3_resource: A Boto3 Amazon S3 resource.
        :param sqs_resource: A Boto3 Amazon SQS resource.
        """
        self.textract_client = textract_client
        self.s3_resource = s3_resource
        self.sqs_resource = sqs_resource


    def start_analysis_job(
        self,
        bucket_name,
        document_file_name,
        feature_types,
        sns_topic_arn,
        sns_role_arn,
    ):
        """
        Starts an asynchronous job to detect text and additional elements, such as
        forms or tables, in an image stored in an Amazon S3 bucket. Textract publishes
        a notification to the specified Amazon SNS topic when the job completes.
        The image must be in PNG, JPG, or PDF format.

        :param bucket_name: The name of the Amazon S3 bucket that contains the image.
        :param document_file_name: The name of the document image stored in Amazon S3.
        :param feature_types: The types of additional document features to detect.
        :param sns_topic_arn: The Amazon Resource Name (ARN) of an Amazon SNS topic
                              where job completion notification is published.
        :param sns_role_arn: The ARN of an AWS Identity and Access Management (IAM)
                             role that can be assumed by Textract and grants permission
                             to publish to the Amazon SNS topic.
        :return: The ID of the job.
        """
        try:
            response = self.textract_client.start_document_analysis(
                DocumentLocation={
                    "S3Object": {"Bucket": bucket_name, "Name": document_file_name}
                },
                NotificationChannel={
                    "SNSTopicArn": sns_topic_arn,
                    "RoleArn": sns_role_arn,
                },
                FeatureTypes=feature_types,
            )
            job_id = response["JobId"]
            logger.info(
                "Started text analysis job %s on %s.", job_id, document_file_name
            )
        except ClientError:
            logger.exception("Couldn't analyze text in %s.", document_file_name)
            raise
        else:
            return job_id
```
+  有关 API 的详细信息，请参阅适用[StartDocumentAnalysis](https://docs.aws.amazon.com/goto/boto3/textract-2018-06-27/StartDocumentAnalysis)于 *Python 的AWS SDK (Boto3) API 参考*。

### `StartDocumentTextDetection`
<a name="textract_StartDocumentTextDetection_python_3_topic"></a>

以下代码示例演示了如何使用 `StartDocumentTextDetection`。

**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/textract#code-examples)中查找完整示例，了解如何进行设置和运行。
启动异步任务以检测文档中的文本。  

```
class TextractWrapper:
    """Encapsulates Textract functions."""

    def __init__(self, textract_client, s3_resource, sqs_resource):
        """
        :param textract_client: A Boto3 Textract client.
        :param s3_resource: A Boto3 Amazon S3 resource.
        :param sqs_resource: A Boto3 Amazon SQS resource.
        """
        self.textract_client = textract_client
        self.s3_resource = s3_resource
        self.sqs_resource = sqs_resource


    def start_detection_job(
        self, bucket_name, document_file_name, sns_topic_arn, sns_role_arn
    ):
        """
        Starts an asynchronous job to detect text elements in an image stored in an
        Amazon S3 bucket. Textract publishes a notification to the specified Amazon SNS
        topic when the job completes.
        The image must be in PNG, JPG, or PDF format.

        :param bucket_name: The name of the Amazon S3 bucket that contains the image.
        :param document_file_name: The name of the document image stored in Amazon S3.
        :param sns_topic_arn: The Amazon Resource Name (ARN) of an Amazon SNS topic
                              where the job completion notification is published.
        :param sns_role_arn: The ARN of an AWS Identity and Access Management (IAM)
                             role that can be assumed by Textract and grants permission
                             to publish to the Amazon SNS topic.
        :return: The ID of the job.
        """
        try:
            response = self.textract_client.start_document_text_detection(
                DocumentLocation={
                    "S3Object": {"Bucket": bucket_name, "Name": document_file_name}
                },
                NotificationChannel={
                    "SNSTopicArn": sns_topic_arn,
                    "RoleArn": sns_role_arn,
                },
            )
            job_id = response["JobId"]
            logger.info(
                "Started text detection job %s on %s.", job_id, document_file_name
            )
        except ClientError:
            logger.exception("Couldn't detect text in %s.", document_file_name)
            raise
        else:
            return job_id
```
+  有关 API 的详细信息，请参阅适用[StartDocumentTextDetection](https://docs.aws.amazon.com/goto/boto3/textract-2018-06-27/StartDocumentTextDetection)于 *Python 的AWS SDK (Boto3) API 参考*。

## 场景
<a name="scenarios"></a>

### 创建 Amazon Textract 浏览器应用程序
<a name="cross_TextractExplorer_python_3_topic"></a>

以下代码示例演示如何通过交互式应用程序探索 Amazon Textract 输出。

**适用于 Python 的 SDK（Boto3）**  
 演示如何 适用于 Python (Boto3) 的 AWS SDK 与 Amazon Textract 配合使用来检测文档图像中的文本、表单和表格元素。输入图像和 Amazon Textract 输出在 Tkinter 应用程序中显示，该应用程序可让您探索检测到的元素。  
+ 将文档图像提交到 Amazon Textract 并探索检测到的元素的输出。
+ 将图像直接提交到 Amazon Textract，或通过 Amazon Simple Storage Service（Amazon S3）桶提交图像。
+ 使用异步 APIs 启动任务，该任务在任务完成时向亚马逊简单通知服务 (Amazon SNS) Simple Notification Service 主题发布通知。
+ 轮询 Amazon Simple Queue Service (Amazon SQS) 队列，以获取任务完成消息并显示结果。
 有关如何设置和运行的完整源代码和说明，请参阅上的完整示例[GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/cross_service/textract_explorer)。  

**本示例中使用的服务**
+ Amazon Cognito Identity
+ Amazon S3
+ Amazon SNS
+ Amazon SQS
+ Amazon Textract

### 检测从图像中提取的文本中的实体
<a name="cross_TextractComprehendDetectEntities_python_3_topic"></a>

以下代码示例显示了如何使用 Amazon Comprehend 检测 Amazon Textract 从存储在 Amazon S3 内的图像中提取的文本中的实体。

**适用于 Python 的 SDK（Boto3）**  
 演示如何使用 Jupyter 笔记本 适用于 Python (Boto3) 的 AWS SDK 中的来检测从图像中提取的文本中的实体。此示例使用 Amazon Textract 从存储在 Amazon Simple Storage Service (Amazon S3) 内的图像中提取文本，并使用 Amazon Comprehend 检测提取文本中的实体。  
 此示例是 Jupyter 笔记本，必须在可以托管笔记本电脑的环境中运行。有关如何使用 Amazon A SageMaker I 运行示例的说明，请参阅 [TextractAndComprehendNotebook.ipyn](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/cross_service/textract_comprehend_notebook/TextractAndComprehendNotebook.ipynb) b 中的说明。  
 有关如何设置和运行的完整源代码和说明，请参阅上的完整示例[GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/cross_service/textract_comprehend_notebook#readme)。  

**本示例中使用的服务**
+ Amazon Comprehend
+ Amazon S3
+ Amazon Textract