wip: add backup function

Author: geeksilva97

src/node_sqlite.cc

@@ -1,3 +1,4 @@
+#include "async_wrap-inl.h"
 #include "node_sqlite.h"
 #include <path.h>
 #include "base_object-inl.h"
@@ -9,13 +10,15 @@
 #include "node_mem-inl.h"
 #include "sqlite3.h"
 #include "util-inl.h"
+#include "threadpoolwork-inl.h"
 
 #include <cinttypes>
 
 namespace node {
 namespace sqlite {
 
 using v8::Array;
+using v8::HandleScope;
 using v8::ArrayBuffer;
 using v8::BigInt;
 using v8::Boolean;
@@ -40,6 +43,7 @@ using v8::NewStringType;
 using v8::Null;
 using v8::Number;
 using v8::Object;
+using v8::Promise;
 using v8::SideEffectType;
 using v8::String;
 using v8::TryCatch;
@@ -128,6 +132,54 @@ inline void THROW_ERR_SQLITE_ERROR(Isolate* isolate, int errcode) {
   isolate->ThrowException(error);
 }
 
+class BackupJob: public ThreadPoolWork {
+  public:
+    explicit BackupJob(Environment* env,
+        DatabaseSync* source,
+        Local<Promise::Resolver> resolver,
+        const char* source_name,
+        const char* destination_name,
+        int pages,
+        int sleep) : ThreadPoolWork(env, "node_sqlite3.BackupJob"),
+    env_(env),
+    source_(source),
+    /* resolver_(env->isolate(), resolver), */
+    source_name_(source_name),
+    destination_name_(destination_name),
+    pages_(pages),
+    sleep_(sleep) {
+      resolver_.Reset(env->isolate(), resolver);
+    }
+
+  void DoThreadPoolWork() override {
+    std::cout << "Gotta do a backup here" << std::endl;
+  }
+
+  void AfterThreadPoolWork(int status) override {
+    HandleScope handle_scope(env()->isolate());
+
+    if (!resolver_.IsEmpty()) {
+      Local<Promise::Resolver> resolver = Local<Promise::Resolver>::New(env()->isolate(), resolver_);
+      Local<String> message = String::NewFromUtf8(env()->isolate(), "Backup completed", NewStringType::kNormal).ToLocalChecked();
+
+      // Resolve the promise with a value (Null in this case)
+      resolver->Resolve(env()->context(), message).ToChecked();
+    }
+  }
+
+  private:
+
+  Environment* env() const { return env_; }
+
+  Environment* env_;
+  DatabaseSync* source_;
+  Global<Promise::Resolver> resolver_;
+  std::string source_name_;
+  std::string destination_name_;
+  int pages_;
+  int sleep_;
+};
+
 class UserDefinedFunction {
  public:
   explicit UserDefinedFunction(Environment* env,
@@ -533,6 +585,20 @@ void DatabaseSync::Exec(const FunctionCallbackInfo<Value>& args) {
   CHECK_ERROR_OR_THROW(env->isolate(), db->connection_, r, SQLITE_OK, void());
 }
 
+void DatabaseSync::Backup(const FunctionCallbackInfo<Value>& args) {
+  DatabaseSync* db;
+  ASSIGN_OR_RETURN_UNWRAP(&db, args.This());
+  Environment* env = Environment::GetCurrent(args);
+  Local<Promise::Resolver> resolver = Promise::Resolver::New(env->context())
+                                          .ToLocalChecked()
+                                          .As<Promise::Resolver>();
+
+  args.GetReturnValue().Set(resolver->GetPromise());
+
+  BackupJob* job = new BackupJob(env, db, resolver, "main", "main", 100, 250);
+  job->ScheduleWork();
+}
+
 void DatabaseSync::CustomFunction(const FunctionCallbackInfo<Value>& args) {
   DatabaseSync* db;
   ASSIGN_OR_RETURN_UNWRAP(&db, args.This());
@@ -1718,6 +1784,7 @@ static void Initialize(Local<Object> target,
   SetProtoMethod(isolate, db_tmpl, "close", DatabaseSync::Close);
   SetProtoMethod(isolate, db_tmpl, "prepare", DatabaseSync::Prepare);
   SetProtoMethod(isolate, db_tmpl, "exec", DatabaseSync::Exec);
+  SetProtoMethod(isolate, db_tmpl, "backup", DatabaseSync::Backup);
   SetProtoMethod(isolate, db_tmpl, "function", DatabaseSync::CustomFunction);
   SetProtoMethod(
       isolate, db_tmpl, "createSession", DatabaseSync::CreateSession);

src/node_sqlite.h

@@ -57,6 +57,7 @@ class DatabaseSync : public BaseObject {
   static void Close(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void Prepare(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void Exec(const v8::FunctionCallbackInfo<v8::Value>& args);
+  static void Backup(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void CustomFunction(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void CreateSession(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void ApplyChangeset(const v8::FunctionCallbackInfo<v8::Value>& args);
@@ -81,6 +82,7 @@ class DatabaseSync : public BaseObject {
   bool enable_load_extension_;
   sqlite3* connection_;
 
+	std::set<sqlite3_backup*> backups_;
   std::set<sqlite3_session*> sessions_;
   std::unordered_set<StatementSync*> statements_;