使用 AWS SDK 创建 Lookout for Vision 清单文件

class Datasets:

    @staticmethod
    def create_manifest_file_s3(s3_resource, image_s3_path, manifest_s3_path):
        """
        Creates a manifest file and uploads to Amazon S3.

        :param s3_resource: A Boto3 Amazon S3 resource.
        :param image_s3_path: The Amazon S3 path to the images referenced by the
                              manifest file. The images must be in an Amazon S3 bucket
                              with the following folder structure.
                                s3://amzn-s3-demo-bucket/<train or test>/
                                    normal/
                                    anomaly/
                              Place normal images in the normal folder and anomalous
                              images in the anomaly folder.
        :param manifest_s3_path: The Amazon S3 location in which to store the created
                                 manifest file.
        """
        output_manifest_file = "temp.manifest"
        try:
            # Current date and time in manifest file format.
            dttm = datetime.now().strftime("%Y-%m-%dT%H:%M:%S.%f")

            # Get bucket and folder from image and manifest file paths.
            bucket, prefix = image_s3_path.replace("s3://", "").split("/", 1)
            if prefix[-1] != "/":
                prefix += "/"
            manifest_bucket, manifest_prefix = manifest_s3_path.replace(
                "s3://", ""
            ).split("/", 1)

            with open(output_manifest_file, "w") as mfile:
                logger.info("Creating manifest file")
                src_bucket = s3_resource.Bucket(bucket)

                # Create JSON lines for anomalous images.
                for obj in src_bucket.objects.filter(
                    Prefix=prefix + "anomaly/", Delimiter="/"
                ):
                    image_path = f"s3://{src_bucket.name}/{obj.key}"
                    manifest = Datasets.create_json_line(image_path, "anomaly", dttm)
                    mfile.write(json.dumps(manifest) + "\n")

                # Create json lines for normal images.
                for obj in src_bucket.objects.filter(
                    Prefix=prefix + "normal/", Delimiter="/"
                ):
                    image_path = f"s3://{src_bucket.name}/{obj.key}"
                    manifest = Datasets.create_json_line(image_path, "normal", dttm)
                    mfile.write(json.dumps(manifest) + "\n")

            logger.info("Uploading manifest file to %s", manifest_s3_path)
            s3_resource.Bucket(manifest_bucket).upload_file(
                output_manifest_file, manifest_prefix
            )
        except ClientError:
            logger.exception("Error uploading manifest.")
            raise
        except Exception:
            logger.exception("Error uploading manifest.")
            raise
        else:
            logger.info("Completed manifest file creation and upload.")
        finally:
            try:
                os.remove(output_manifest_file)
            except FileNotFoundError:
                pass

    @staticmethod
    def create_json_line(image, class_name, dttm):
        """
        Creates a single JSON line for an image.

        :param image: The S3 location for the image.
        :param class_name: The class of the image (normal or anomaly)
        :param dttm: The date and time that the JSON is created.
        """

        label = 0
        if class_name == "normal":
            label = 0
        elif class_name == "anomaly":
            label = 1
        else:
            logger.error("Unexpected label value: %s for %s", label, image)
            raise Exception(f"Unexpected label value: {label} for {image}")

        manifest = {
            "source-ref": image,
            "anomaly-label": label,
            "anomaly-label-metadata": {
                "confidence": 1,
                "job-name": "labeling-job/anomaly-label",
                "class-name": class_name,
                "human-annotated": "yes",
                "creation-date": dttm,
                "type": "groundtruth/image-classification",
            },
        }
        return manifest