GitHub - h2337/cppdataloader: cppdataloader is a batching and caching library for C++17 (original) (raw)

cppdataloader

cppdataloader is a batching and caching library for C++17.

cppdataloader is a generic utility to be used as part of your application's data fetching layer to provide a simplified and consistent API over various remote data sources such as databases or web services via batching and caching.

Features

• Batching
• Caching
• Direct dispatch
• Timeout dispatch
• Empty values

Quickstart

cppq is a header-only library with no dependencies.

Just include the header: #include "cppdataloader.h".

Example

#include "cppdataloader.hpp"

#include

class User { public: User(long _id): id(_id) {} long id; };

class UserBatchLoader : public BatchLoader<long, User> { public: std::vector load(std::vector userIds) const override { auto result = std::vector(); // Make a DB call here or something and pass in userIds to SELECT and return for (auto userId : userIds) result.push_back(User(userId)); // Results should be in the same order as passed-in IDs return result; } };

int main(int argc, char *argv[]) { UserBatchLoader userBatchLoader = UserBatchLoader(); DataLoader<long, User> userLoader = DataLoader(userBatchLoader);

std::future load1 = userLoader.load(1); std::future load2 = userLoader.load(2); // Since this fetches the same ID of 1, it will return the cached value std::future load3 = userLoader.load(1);

// Both calls to load will be batched and executed with this call userLoader.dispatch();

std::cout << load1.get().id << " " << load2.get().id << " " << load3.get().id << std::endl; }

License

cppdataloader is MIT-licensed.