Files
MapLibreParticleLab/include/mbgl/storage/file_source.hpp
2019-05-14 11:29:24 +03:00

51 lines
1.9 KiB
C++

#pragma once
#include <mbgl/actor/actor_ref.hpp>
#include <mbgl/storage/response.hpp>
#include <mbgl/storage/resource.hpp>
#include <mbgl/util/async_request.hpp>
#include <functional>
#include <memory>
namespace mbgl {
class ResourceOptions;
class ResourceTransform;
class FileSource {
public:
FileSource(const FileSource&) = delete;
FileSource& operator=(const FileSource&) = delete;
virtual ~FileSource() = default;
using Callback = std::function<void (Response)>;
// Request a resource. The callback will be called asynchronously, in the same
// thread as the request was made. This thread must have an active RunLoop. The
// request may be cancelled before completion by releasing the returned AsyncRequest.
// If the request is cancelled before the callback is executed, the callback will
// not be executed.
virtual std::unique_ptr<AsyncRequest> request(const Resource&, Callback) = 0;
// When a file source supports consulting a local cache only, it must return true.
// Cache-only requests are requests that aren't as urgent, but could be useful, e.g.
// to cover part of the map while loading. The FileSource should only do cheap actions to
// retrieve the data, e.g. load it from a cache, but not from the internet.
virtual bool supportsCacheOnlyRequests() const {
return false;
}
// Singleton for obtaining the shared platform-specific file source. A single instance of a file source is provided
// for each unique combination of a Mapbox API base URL, access token, cache path and platform context.
static std::shared_ptr<FileSource> getSharedFileSource(const ResourceOptions&);
protected:
FileSource() = default;
// Factory for creating a platform-specific file source.
static std::shared_ptr<FileSource> createPlatformFileSource(const ResourceOptions&);
};
} // namespace mbgl