Duplicates in required field of ObjectType JSON schema

[MeltyBot]

Migrated from GitLab: https://gitlab.com/meltano/sdk/-/issues/340

Originally created by @ReubenFrankel on 2022-03-02 12:06:24

---

Summary

https://gitlab.com/meltano/sdk/-/merge_requests/250#note_859372536

If any Property objects have a non-unique name (i.e. duplicates) and are also required, in the resulting schema dictionary:

• properties are correctly merged by name
• required will contain a name for each duplicate property

Steps to reproduce

properties = [
    Property("id", StringType),
    Property("email", StringType, True),
    Property("email", StringType, True), # duplicate required property
    Property("username", StringType, True),
    Property("phone_number", StringType),
]

ObjectType(*properties).type_dict

{
    "type": "object",
    "properties": {
        "id": {
            "type": [
                "string",
                "null",
            ],
        },
        "email": {
            "type": ["string"],
        },
        "username": {
            "type": ["string"],
        },
        "phone_number": {
            "type": [
                "string",
                "null",
            ],
        }
    },
    "required": [
        "email",
        "email",
        "username",
    ],
}

What is the current bug behavior?

Required properties with the same name are merged in properties, but the names remain duplicated in required.

What is the expected correct behavior?

properties = [
    Property("id", StringType),
    Property("email", StringType, True),
    Property("email", StringType, True), # duplicate required property
    Property("username", StringType, True),
    Property("phone_number", StringType),
]

ObjectType(*properties).type_dict

{
    "type": "object",
    "properties": {
        "id": {
            "type": [
                "string",
                "null",
            ],
        },
        "email": {
            "type": ["string"],
        },
        "username": {
            "type": ["string"],
        },
        "phone_number": {
            "type": [
                "string",
                "null",
            ],
        }
    },
    "required": [
        "email",
        "username",
    ],
}

Possible fixes

https://gitlab.com/meltano/sdk/-/blob/main/singer_sdk/typing.py#L281

# see https://stackoverflow.com/a/7961390
result["required"] = list(dict.fromkeys(required)) # filter duplicates from list

[MeltyBot]

View 2 previous comments from the original issue on GitLab

[stale]

This has been marked as stale because it is unassigned, and has not had recent activity. It will be closed after 21 days if no further activity occurs. If this should never go stale, please add the evergreen label, or request that it be added.

[edgarrmondragon]

Closed by #1214