[jeferson0306]

POST /validate/batch
{"items":[
  {"id":"titular",  "key":"cpf",  "value":"529.982.247-25"},
  {"id":"empresa",  "key":"cnpj", "value":"33.000.167/0001-01"},
  {"id":"estadual", "key":"ie",   "value":"0100482300112", "qualifier":"AC"}
]}

A registration form with eight fields was eight round trips. Now it is one.

The precondition

Adding a second endpoint over the same validators would have created two implementations of the same dispatch, free to drift apart. So every validator now lives in one table in utils/dispatch.go, and both endpoints read from it:

var validators = map[string]validatorFunc{
    "cpf":  ..., "cnpj": ..., "ie": ..., "pix": ...,
}

A document added there appears on both endpoints at once. The single-value handler lost its fourteen-branch if/else chain in the process, and its parameter counting is now derived from the same table rather than from a list kept by hand next to it — which is what let CNPJ slip past the one-per-request guard when it was added.

The existing handler tests passed unchanged through the refactor, which is the evidence that behaviour was preserved.

Design decisions worth arguing with

Items are a list, not an object keyed by document type. A form can carry two CPFs — a customer and a guarantor — and an object would silently keep only the last. Each item may carry an id, echoed back untouched, so results line up with the caller's own fields without depending on ordering.

A batch that ran answers 200 even when items failed validation. The single endpoint answers 422 for an invalid value because there the value is the whole request. Here it is one line of many, and failing the response would discard the results that did pass. The summary tells you what happened:

"summary": { "total": 5, "valid": 4, "invalid": 1 }

An unknown document type is UNKNOWN_KEY on that item, not an invalid value, and does not fail the batch. Calling it "invalid" would suggest the value had been checked and rejected; discarding nine good results over one typo helps nobody.

Bounded on both axes

At most 100 items — a form has tens of fields, not thousands, and anything past that is a mistake or an attempt to use the service as free compute. The body is capped at 1 MB before parsing, so a large request cannot exhaust memory ahead of the item check. Unknown JSON fields are refused rather than ignored: a caller who misspells items deserves to be told, not handed an empty summary.

The parser error is never echoed

A JSON decoding error can quote the body, and the body is exactly the personal data that must not travel back out. A test asserts a submitted CPF cannot be found anywhere in the failure message — the same rule as the logging fix in #4, applied to the other direction of travel.

Tests

Eight new cases; handlers coverage 79% → 94%. CORS now advertises POST, and the Swagger spec carries the new route.