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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef mozilla_dom_IdentityNetworkHelpers_h
#define mozilla_dom_IdentityNetworkHelpers_h
#include "mozilla/dom/Promise.h"
#include "mozilla/dom/Promise-inl.h"
#include "mozilla/dom/Request.h"
#include "mozilla/dom/Response.h"
#include "mozilla/dom/WindowGlobalParent.h"
#include "mozilla/MozPromise.h"
namespace mozilla::dom {
// Helper to get a JSON structure via a Fetch.
// The Request must already be built and T should be a webidl type with
// annotation GenerateConversionToJS so it has an Init method.
template <typename T, typename TPromise = MozPromise<T, nsresult, true>>
RefPtr<TPromise> FetchJSONStructure(Request* aRequest) {
MOZ_ASSERT(XRE_IsParentProcess());
// Create the returned Promise
RefPtr<typename TPromise::Private> resultPromise =
new typename TPromise::Private(__func__);
// Fetch the provided request
RequestOrUTF8String fetchInput;
fetchInput.SetAsRequest() = aRequest;
RootedDictionary<RequestInit> requestInit(RootingCx());
IgnoredErrorResult error;
RefPtr<Promise> fetchPromise =
FetchRequest(aRequest->GetParentObject(), fetchInput, requestInit,
CallerType::System, error);
if (NS_WARN_IF(error.Failed())) {
resultPromise->Reject(NS_ERROR_FAILURE, __func__);
return resultPromise;
}
RefPtr<PromiseNativeHandler> reject =
new MozPromiseRejectOnDestruction{resultPromise, __func__};
// Handle the response
fetchPromise->AddCallbacksWithCycleCollectedArgs(
[resultPromise, reject](JSContext* aCx, JS::Handle<JS::Value> aValue,
ErrorResult&) {
// Get the Response object from the argument to the callback
if (NS_WARN_IF(!aValue.isObject())) {
resultPromise->Reject(NS_ERROR_FAILURE, __func__);
return;
}
JS::Rooted<JSObject*> obj(aCx, &aValue.toObject());
MOZ_ASSERT(obj);
Response* response = nullptr;
if (NS_WARN_IF(NS_FAILED(UNWRAP_OBJECT(Response, &obj, response)))) {
resultPromise->Reject(NS_ERROR_FAILURE, __func__);
return;
}
// Make sure the request was a success
if (!response->Ok()) {
resultPromise->Reject(NS_ERROR_FAILURE, __func__);
return;
}
// Parse the body into JSON, which must be done async
IgnoredErrorResult error;
RefPtr<Promise> jsonPromise = response->ConsumeBody(
aCx, BodyConsumer::ConsumeType::CONSUME_JSON, error);
if (NS_WARN_IF(error.Failed())) {
resultPromise->Reject(NS_ERROR_FAILURE, __func__);
return;
}
// Handle the parsed JSON from the Response body
jsonPromise->AddCallbacksWithCycleCollectedArgs(
[resultPromise](JSContext* aCx, JS::Handle<JS::Value> aValue,
ErrorResult&) {
// Parse the JSON into the correct type, validating fields and
// types
T result;
bool success = result.Init(aCx, aValue);
if (!success) {
resultPromise->Reject(NS_ERROR_FAILURE, __func__);
return;
}
resultPromise->Resolve(result, __func__);
},
[resultPromise](JSContext*, JS::Handle<JS::Value> aValue,
ErrorResult&) {
resultPromise->Reject(
Promise::TryExtractNSResultFromRejectionValue(aValue),
__func__);
});
jsonPromise->AppendNativeHandler(reject);
},
[resultPromise](JSContext*, JS::Handle<JS::Value> aValue, ErrorResult&) {
resultPromise->Reject(
Promise::TryExtractNSResultFromRejectionValue(aValue), __func__);
});
fetchPromise->AppendNativeHandler(reject);
return resultPromise;
}
} // namespace mozilla::dom
#endif // mozilla_dom_IdentityNetworkHelpers_h