Fix bulk action annotation

[guan404ming]

Why

The type annotations for bulk action are incorrect, which is found when I dig into tracing ci error in #50443. I think this is independent thus split this from that one.

How

I update the action type with default value. This would affect bulk connection, variable and pool.

before (example value show on swagger)

{
  "actions": [
    {
      "action": "create",
      "entities": [
        {
          "connection_id": "RaWlyerMwZB4HWkvpQ",
          "conn_type": "string",
          "description": "string",
          "host": "string",
          "login": "string",
          "schema": "string",
          "port": 0,
          "password": "string",
          "extra": "string"
        }
      ],
      "action_on_existence": "fail"
    },
    {
      "action": "create",
      "entities": [
        {
          "connection_id": "qWspL.KI..EomTj-Z003JLNXUZ-c2iEB5y8OhfvShMBg",
          "conn_type": "string",
          "description": "string",
          "host": "string",
          "login": "string",
          "schema": "string",
          "port": 0,
          "password": "string",
          "extra": "string"
        }
      ],
      "action_on_non_existence": "fail"
    },
    {
      "action": "create",
      "entities": [
        "string"
      ],
      "action_on_non_existence": "fail"
    }
  ]
}

after (example value show on swagger)

{
  "actions": [
    {
      "action": "create",
      "entities": [
        {
          "connection_id": "X_yo6QuSl9u4HVXxB9YNy.mHdmnNzcPCVjy3Fa9D2IHrwY7tkvlX",
          "conn_type": "string",
          "description": "string",
          "host": "string",
          "login": "string",
          "schema": "string",
          "port": 0,
          "password": "string",
          "extra": "string"
        }
      ],
      "action_on_existence": "fail"
    },
    {
      "action": "update",
      "entities": [
        {
          "connection_id": "8sJhEpjO6-Ey9IyPGjL448pqIXIIu3bo9Vy4Sy1q2NoL5WS3bwNT2x6",
          "conn_type": "string",
          "description": "string",
          "host": "string",
          "login": "string",
          "schema": "string",
          "port": 0,
          "password": "string",
          "extra": "string"
        }
      ],
      "action_on_non_existence": "fail"
    },
    {
      "action": "delete",
      "entities": [
        "string"
      ],
      "action_on_non_existence": "fail"
    }
  ]
}

---

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[bugraoz93]

Thanks a lot! Looks good overall! Small question :)

[pierrejeambrun]

Thanks

[pierrejeambrun]

This is weird, since the action is not required, but this is the discriminator, so how can pydantic know what's the relevant deserializer if the action is not specified.

[pierrejeambrun]

Removing the action will yield a discriminator error.

[pierrejeambrun]

Maybe changing the enum to literal and do action: Literal[BulkAction.CREATE] = Field(description="The action to be performed on the entit...

[pierrejeambrun]

action should be required.

[pierrejeambrun]

I've pushed a commit to improve it, let me know what you think.

[bugraoz93]

Great, thanks, Pierre! Making Literal makes sense and eliminates the stated problem while making them limited to being properly used by the discriminator.
This was exactly what I mentioned in my comment. #50852 (comment).

[pierrejeambrun]

Yes, the tips for it to work was to make the enum extend string too.

[guan404ming]

Make sense! Thanks for fixing this and the tip is really helpful.
LGTM.

stalte, has been fixed