Revert changes made in pr #537 to change DataTransfer.data typehint.

[alexmclarty]

According to this issue, a PR was made to change the type of DataTransfer.data to Any rather than str.

This PR makes the type str instead of Any.

[OrangeTux]

@mdwcrft Does this PR have any impact on our internal codebase?

[mdwcrft]

As discussed offline I think this should still be of type Any - but we will clarify with the OCA what their definition of anyType means

[proelke]

The schema specifies a string here.

[Jared-Newell-Mobility]

I would suggest also that we add a comment to explain this complication in the standard in detail - I might prevent it reverted again into the future?

[alexmclarty]

@Jared-Newell-Mobility ready for review (once tests pass)

[Jared-Newell-Mobility]

I've check over things again, I don't see a type specified in the schema. There is clearly a discrepancy between the descriptions 1. Optional. Data without specified length or format, in response to request and 2. text, data without specified length or format.

Schema normally trumps; I'm going to raise it with the OCA at minimum this might be cleared up also for others in the next Errata

  "$schema": "http://json-schema.org/draft-06/schema#",
  "$id": "urn:OCPP:Cp:2:2020:3:DataTransferRequest",
  "comment": "OCPP 2.0.1 FINAL",
  "definitions": {
    "CustomDataType": {
      "description": "This class does not get 'AdditionalProperties = false' in the schema generation, so it can be extended with arbitrary JSON properties to allow adding custom data.",
      "javaType": "CustomData",
      "type": "object",
      "properties": {
        "vendorId": {
          "type": "string",
          "maxLength": 255
        }
      },
      "required": [
        "vendorId"
      ]
    }
  },
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "customData": {
      "$ref": "#/definitions/CustomDataType"
    },
    "messageId": {
      "description": "May be used to indicate a specific message or implementation.\r\n",
      "type": "string",
      "maxLength": 50
    },
-----------------
    "data": {
      "description": "Data without specified length or format. This needs to be decided by both parties (Open to implementation).\r\n"
    },
-----------------
    "vendorId": {
      "description": "This identifies the Vendor specific implementation\r\n\r\n",
      "type": "string",
      "maxLength": 255
    }
  },
  "required": [
    "vendorId"
  ]
}```

```{
  "$schema": "http://json-schema.org/draft-06/schema#",
  "$id": "urn:OCPP:Cp:2:2020:3:DataTransferResponse",
  "comment": "OCPP 2.0.1 FINAL",
  "definitions": {
    "CustomDataType": {
      "description": "This class does not get 'AdditionalProperties = false' in the schema generation, so it can be extended with arbitrary JSON properties to allow adding custom data.",
      "javaType": "CustomData",
      "type": "object",
      "properties": {
        "vendorId": {
          "type": "string",
          "maxLength": 255
        }
      },
      "required": [
        "vendorId"
      ]
    },
    "DataTransferStatusEnumType": {
      "description": "This indicates the success or failure of the data transfer.\r\n",
      "javaType": "DataTransferStatusEnum",
      "type": "string",
      "additionalProperties": false,
      "enum": [
        "Accepted",
        "Rejected",
        "UnknownMessageId",
        "UnknownVendorId"
      ]
    },
    "StatusInfoType": {
      "description": "Element providing more information about the status.\r\n",
      "javaType": "StatusInfo",
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "customData": {
          "$ref": "#/definitions/CustomDataType"
        },
        "reasonCode": {
          "description": "A predefined code for the reason why the status is returned in this response. The string is case-insensitive.\r\n",
          "type": "string",
          "maxLength": 20
        },
        "additionalInfo": {
          "description": "Additional text to provide detailed information.\r\n",
          "type": "string",
          "maxLength": 512
        }
      },
      "required": [
        "reasonCode"
      ]
    }
  },
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "customData": {
      "$ref": "#/definitions/CustomDataType"
    },
    "status": {
      "$ref": "#/definitions/DataTransferStatusEnumType"
    },
    "statusInfo": {
      "$ref": "#/definitions/StatusInfoType"
    },
-------------------------
    "data": {
      "description": "Data without specified length or format, in response to request.\r\n"
    }
-------------------------
  },
  "required": [
    "status"
  ]
}```

[Jared-Newell-Mobility]

The OCA has confirmed that AnyType is any type as expected and is reflected in the schema. However, in OCPP 2.0.1 Part 2, Section 2.1.4. Primitive Datatypes the description for AnyType could be improved on, that is to remove the word "Text". This has been raised. So given this, I will close this PR as the current type used is correct.

[OrangeTux]

Thanks for your effort @Jared-Newell-Mobility