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prefect.blocks.system

DateTime

Bases: Block

A block that represents a datetime. Deprecated, please use Variables to store datetime data instead.

Attributes:

Name Type Description
value DateTime

An ISO 8601-compatible datetime value.
Example

Load a stored JSON value:

from prefect.blocks.system import DateTime

data_time_block = DateTime.load("BLOCK_NAME")
Source code in src/prefect/blocks/system.py 
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@deprecated_class(
    start_date="Jun 2024",
    end_date="Jun 2025",
    help="Use Variables to store datetime data instead.",
)
class DateTime(Block):
    """
    A block that represents a datetime. Deprecated, please use Variables to store datetime data instead.

    Attributes:
        value: An ISO 8601-compatible datetime value.

    Example:
        Load a stored JSON value:
        ```python
        from prefect.blocks.system import DateTime

        data_time_block = DateTime.load("BLOCK_NAME")
        ```
    """

    _block_type_name = "Date Time"
    _logo_url = "https://cdn.sanity.io/images/3ugk85nk/production/8b3da9a6621e92108b8e6a75b82e15374e170ff7-48x48.png"
    _documentation_url = "https://docs.prefect.io/latest/develop/blocks"

    value: PydanticDateTime = Field(
        default=...,
        description="An ISO 8601-compatible datetime value.",
    )

JSON

Bases: Block

A block that represents JSON. Deprecated, please use Variables to store JSON data instead.

Attributes:

Name Type Description
value Any

A JSON-compatible value.
Example

Load a stored JSON value:

from prefect.blocks.system import JSON

json_block = JSON.load("BLOCK_NAME")
Source code in src/prefect/blocks/system.py 
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@deprecated_class(
    start_date="Jun 2024",
    end_date="Jun 2025",
    help="Use Variables to store json data instead.",
)
class JSON(Block):
    """
    A block that represents JSON. Deprecated, please use Variables to store JSON data instead.

    Attributes:
        value: A JSON-compatible value.

    Example:
        Load a stored JSON value:
        ```python
        from prefect.blocks.system import JSON

        json_block = JSON.load("BLOCK_NAME")
        ```
    """

    _logo_url = "https://cdn.sanity.io/images/3ugk85nk/production/4fcef2294b6eeb423b1332d1ece5156bf296ff96-48x48.png"
    _documentation_url = "https://docs.prefect.io/latest/develop/blocks"

    value: Any = Field(default=..., description="A JSON-compatible value.")

Secret

Bases: Block, Generic[T]

A block that represents a secret value. The value stored in this block will be obfuscated when this block is viewed or edited in the UI.

Attributes:

Name Type Description
value Union[SecretStr, Secret[T]]

A value that should be kept secret.
Example 
from prefect.blocks.system import Secret

Secret(value="sk-1234567890").save("BLOCK_NAME", overwrite=True)

secret_block = Secret.load("BLOCK_NAME")

# Access the stored secret
secret_block.get()
Source code in src/prefect/blocks/system.py 
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class Secret(Block, Generic[T]):
    """
    A block that represents a secret value. The value stored in this block will be obfuscated when
    this block is viewed or edited in the UI.

    Attributes:
        value: A value that should be kept secret.

    Example:
        ```python
        from prefect.blocks.system import Secret

        Secret(value="sk-1234567890").save("BLOCK_NAME", overwrite=True)

        secret_block = Secret.load("BLOCK_NAME")

        # Access the stored secret
        secret_block.get()
        ```
    """

    _logo_url = "https://cdn.sanity.io/images/3ugk85nk/production/c6f20e556dd16effda9df16551feecfb5822092b-48x48.png"
    _documentation_url = "https://docs.prefect.io/latest/develop/blocks"

    value: Union[SecretStr, PydanticSecret[T]] = Field(
        default=...,
        description="A value that should be kept secret.",
        examples=["sk-1234567890", {"username": "johndoe", "password": "s3cr3t"}],
        json_schema_extra={
            "writeOnly": True,
            "format": "password",
        },
    )

    @field_validator("value", mode="before")
    def validate_value(
        cls, value: Union[T, SecretStr, PydanticSecret[T]]
    ) -> Union[SecretStr, PydanticSecret[T]]:
        if isinstance(value, (PydanticSecret, SecretStr)):
            return value
        else:
            return PydanticSecret[type(value)](value)

    def get(self) -> T:
        try:
            value = self.value.get_secret_value()
            return json.loads(value)
        except (TypeError, json.JSONDecodeError):
            return value

String

Bases: Block

A block that represents a string. Deprecated, please use Variables to store string data instead.

Attributes:

Name Type Description
value str

A string value.
Example

Load a stored string value:

from prefect.blocks.system import String

string_block = String.load("BLOCK_NAME")
Source code in src/prefect/blocks/system.py 
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@deprecated_class(
    start_date="Jun 2024",
    end_date="Jun 2025",
    help="Use Variables to store string data instead.",
)
class String(Block):
    """
    A block that represents a string. Deprecated, please use Variables to store string data instead.

    Attributes:
        value: A string value.

    Example:
        Load a stored string value:
        ```python
        from prefect.blocks.system import String

        string_block = String.load("BLOCK_NAME")
        ```
    """

    _logo_url = "https://cdn.sanity.io/images/3ugk85nk/production/c262ea2c80a2c043564e8763f3370c3db5a6b3e6-48x48.png"
    _documentation_url = "https://docs.prefect.io/latest/develop/blocks"

    value: str = Field(default=..., description="A string value.")