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#ifndef MBGL_STORAGE_DEFAULT_DEFAULT_FILE_SOURCE_IMPL
#define MBGL_STORAGE_DEFAULT_DEFAULT_FILE_SOURCE_IMPL
#include <mbgl/storage/default_file_source.hpp>
#include <mbgl/storage/asset_context_base.hpp>
#include <mbgl/storage/http_context_base.hpp>
#include <mbgl/util/async_task.hpp>
#include <mbgl/util/noncopyable.hpp>
#include <mbgl/util/chrono.hpp>
#include <mbgl/util/timer.hpp>
#include <set>
#include <unordered_map>
namespace mbgl {
class RequestBase;
class DefaultFileRequest : public FileRequest {
public:
DefaultFileRequest(const Resource& resource_,
DefaultFileSource& fileSource_)
: resource(resource_),
fileSource(fileSource_) {
}
~DefaultFileRequest() {
fileSource.cancel(resource, this);
}
Resource resource;
DefaultFileSource& fileSource;
std::unique_ptr<WorkRequest> workRequest;
};
class DefaultFileRequestImpl : public util::noncopyable {
public:
using Callback = std::function<void (Response)>;
const Resource resource;
std::unique_ptr<WorkRequest> cacheRequest;
RequestBase* realRequest = nullptr;
std::unique_ptr<util::Timer> timerRequest;
inline DefaultFileRequestImpl(const Resource& resource_)
: resource(resource_) {}
~DefaultFileRequestImpl();
// Observer accessors.
void addObserver(FileRequest*, Callback);
void removeObserver(FileRequest*);
bool hasObservers() const;
// Updates/gets the response of this request object.
void setResponse(const std::shared_ptr<const Response>&);
const std::shared_ptr<const Response>& getResponse() const;
// Returns the seconds we have to wait until we need to redo this request. A value of 0
// means that we need to redo it immediately, and a negative value means that we're not setting
// a timeout at all.
Seconds getRetryTimeout() const;
// Checks the currently stored response and replaces it with an idential one, except with the
// stale flag set, if the response is expired.
void checkResponseFreshness();
// Notifies all observers.
void notify();
private:
// Stores a set of all observing Request objects.
std::unordered_map<FileRequest*, Callback> observers;
// The current response data. We're storing it because we can satisfy requests for the same
// resource directly by returning this response object. We also need it to create conditional
// HTTP requests, and to check whether new responses we got changed any data.
std::shared_ptr<const Response> response;
// Counts the number of subsequent failed requests. We're using this value for exponential
// backoff when retrying requests.
int failedRequests = 0;
};
class DefaultFileSource::Impl {
public:
using Callback = std::function<void (Response)>;
Impl(FileCache*, const std::string& = "");
~Impl();
void networkIsReachableAgain();
void add(Resource, FileRequest*, Callback);
void cancel(Resource, FileRequest*);
private:
void update(DefaultFileRequestImpl&);
void startCacheRequest(DefaultFileRequestImpl&);
void startRealRequest(DefaultFileRequestImpl&);
void reschedule(DefaultFileRequestImpl&);
std::unordered_map<Resource, std::unique_ptr<DefaultFileRequestImpl>, Resource::Hash> pending;
FileCache* const cache;
const std::string assetRoot;
const std::unique_ptr<AssetContextBase> assetContext;
const std::unique_ptr<HTTPContextBase> httpContext;
util::AsyncTask reachability;
};
}
#endif
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