JsonPath

class aws_cdk.aws_stepfunctions.JsonPath(*args: Any, **kwargs)

Bases: object

Extract a field from the State Machine data or context that gets passed around between states.

See

https://docs.aws.amazon.com/step-functions/latest/dg/amazon-states-language-paths.html

ExampleMetadata

infused

Example:

# fn: lambda.Function

tasks.LambdaInvoke(self, "Invoke Handler",
    lambda_function=fn,
    result_selector={
        "lambda_output": sfn.JsonPath.string_at("$.Payload"),
        "invoke_request_id": sfn.JsonPath.string_at("$.SdkResponseMetadata.RequestId"),
        "static_value": {
            "foo": "bar"
        },
        "state_name": sfn.JsonPath.string_at("$.State.Name")
    }
)

Attributes

DISCARD = 'DISCARD'
entire_context = '${Token[TOKEN.252]}'
entire_payload = '${Token[TOKEN.253]}'
task_token = '${Token[Task.Token.254]}'

Static Methods

classmethod array(*values)

Make an intrinsic States.Array expression.

Combine any number of string literals or JsonPath expressions into an array.

Use this function if the value of an array element directly has to come from a JSON Path expression (either the State object or the Context object).

If the array contains object literals whose values come from a JSON path expression, you do not need to use this function.

Parameters

values (str) –

See

https://docs.aws.amazon.com/step-functions/latest/dg/amazon-states-language-intrinsic-functions.html

Return type

str

classmethod format(format_string, *values)

Make an intrinsic States.Format expression.

This can be used to embed JSON Path variables inside a format string.

For example:

sfn.JsonPath.format("Hello, my name is {}.", sfn.JsonPath.string_at("$.name"))
Parameters
  • format_string (str) –

  • values (str) –

See

https://docs.aws.amazon.com/step-functions/latest/dg/amazon-states-language-intrinsic-functions.html

Return type

str

classmethod is_encoded_json_path(value)

Determines if the indicated string is an encoded JSON path.

Parameters

value (str) – string to be evaluated.

Return type

bool

classmethod json_to_string(value)

Make an intrinsic States.JsonToString expression.

During the execution of the Step Functions state machine, encode the given object into a JSON string.

For example:

sfn.JsonPath.json_to_string(sfn.JsonPath.object_at("$.someObject"))
Parameters

value (Any) –

See

https://docs.aws.amazon.com/step-functions/latest/dg/amazon-states-language-intrinsic-functions.html

Return type

str

classmethod list_at(path)

Instead of using a literal string list, get the value from a JSON path.

Parameters

path (str) –

Return type

List[str]

classmethod number_at(path)

Instead of using a literal number, get the value from a JSON path.

Parameters

path (str) –

Return type

Union[int, float]

classmethod object_at(path)

Reference a complete (complex) object in a JSON path location.

Parameters

path (str) –

Return type

IResolvable

classmethod string_at(path)

Instead of using a literal string, get the value from a JSON path.

Parameters

path (str) –

Return type

str

classmethod string_to_json(json_string)

Make an intrinsic States.StringToJson expression.

During the execution of the Step Functions state machine, parse the given argument as JSON into its object form.

For example:

sfn.JsonPath.string_to_json(sfn.JsonPath.string_at("$.someJsonBody"))
Parameters

json_string (str) –

See

https://docs.aws.amazon.com/step-functions/latest/dg/amazon-states-language-intrinsic-functions.html

Return type

IResolvable