bag_reader.h File Reference

Abstract base class for VLink bag file playback with time-based seeking and rate control. More...

#include <cstdint>
#include <functional>
#include <future>
#include <memory>
#include <string>
#include <string_view>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#include "../base/bytes.h"
#include "../base/macros.h"
#include "../base/message_loop.h"
#include "../impl/types.h"
#include "./bag_reader_plugin_interface.h"

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Classes
class	vlink::BagReader
	Abstract VLink bag file player with time control, seeking, and integrity tools. More...
struct	vlink::BagReader::Info
	Metadata extracted from the bag file header and index. More...
struct	vlink::BagReader::Info::UrlMeta
	Per-URL statistics extracted from the bag index. More...
struct	vlink::BagReader::Config
	Playback configuration passed to play(). More...

Namespaces
namespace	vlink

Detailed Description

Abstract base class for VLink bag file playback with time-based seeking and rate control.

BagReader is an abstract MessageLoop-based player that reads VLink bag files and replays recorded messages through an OutputCallback. Concrete implementations are DatabaseReader (SQLite-backed) and McapReader (MCAP-format).

Playback features:

• Configurable playback rate (e.g., rate=2.0 for 2x speed).
• Loop playback via the times field (kInfinite = -1 for endless loop).
• Time-range filtering via begin_time and end_time.
• Jump-to-timestamp seeking with optional forced play.
• Per-URL output filtering via Config::filter_urls whitelist.
• Background integrity check, reindex, and fix operations via std::future.
• Plugin interface for custom URL/type mapping.

Playback example

auto reader = vlink::BagReader::create("/data/log.vdb");
reader->register_output_callback([](int64_t ts, const std::string& url,
                                    vlink::ActionType action, const vlink::Bytes& data) {
    VLOG_I("ts=", ts, " url=", url, " size=", data.size());
});
reader->async_run();
 
vlink::BagReader::Config cfg;
cfg.rate = 1.0;
cfg.times = vlink::BagReader::kInfinite;
reader->play(cfg);

Note

• Call async_run() before play().
• check(), reindex(), and fix() run on a background thread and return a std::future<bool> for result polling.
• The file format is auto-detected from the extension by create() (.vcap / .vcapx -> McapReader, otherwise -> DatabaseReader).