Function applyRequestBody

packages/plugins/openapi/src/sdk/invoke.ts:834–912

(
  request: HttpClientRequest.HttpClientRequest,
  contentType: string,
  bodyValue: unknown,
  encoding: Record<string, EncodingObject> | undefined,
)

  | { readonly ok: false; readonly invalidFileField: string };

const applyRequestBody = (
  request: HttpClientRequest.HttpClientRequest,
  contentType: string,
  bodyValue: unknown,
  encoding: Record<string, EncodingObject> | undefined,
): AppliedRequestBody => {
  const sent = (req: HttpClientRequest.HttpClientRequest): AppliedRequestBody => ({
    ok: true,
    request: req,
  });

  if (isJsonContentType(contentType)) {
    const text = typeof bodyValue === "string" ? bodyValue : JSON.stringify(bodyValue);
    return sent(HttpClientRequest.bodyText(request, text, contentType));
  }

  if (isFormUrlEncoded(contentType)) {
    if (typeof bodyValue === "string") {
      return sent(HttpClientRequest.bodyText(request, bodyValue, contentType));
    }
    if (typeof bodyValue === "object" && bodyValue !== null && !Array.isArray(bodyValue)) {
      // Serialize ourselves so OAS3 encoding (style/explode/deepObject)
      // is honored. bodyUrlParams doesn't know about per-field style.
      const serialized = serializeFormUrlEncoded(bodyValue as Record<string, unknown>, encoding);
      return sent(HttpClientRequest.bodyText(request, serialized, contentType));
    }
    // Non-object body — fall back to platform helper (handles URLSearchParams).
    return sent(
      HttpClientRequest.bodyUrlParams(
        request,
        bodyValue as Parameters<typeof HttpClientRequest.bodyUrlParams>[1],
      ),
    );
  }

  if (isMultipartFormData(contentType)) {
    if (bodyValue instanceof FormData) {
      return sent(HttpClientRequest.bodyFormData(request, bodyValue));
    }
    if (typeof bodyValue === "object" && bodyValue !== null) {
      const coerced = coerceFormDataRecord(bodyValue as Record<string, unknown>, encoding);
      if (!coerced.ok) return { ok: false, invalidFileField: coerced.field };
      return sent(HttpClientRequest.bodyFormDataRecord(request, coerced.record));
    }
    // String / primitive under multipart is almost certainly wrong on the
    // caller's end — send it as text with their declared content type and
    // let the server produce a useful error.
    return sent(HttpClientRequest.bodyText(request, String(bodyValue), contentType));
  }

  if (isOctetStream(contentType)) {
    const bytes = toUint8Array(bodyValue);
    if (bytes) return sent(HttpClientRequest.bodyUint8Array(request, bytes, contentType));
    if (typeof bodyValue === "string") {
      return sent(HttpClientRequest.bodyText(request, bodyValue, contentType));
    }
    // Unknown shape — serialize as JSON so at least the payload is visible.
    return sent(HttpClientRequest.bodyText(request, JSON.stringify(bodyValue), contentType));