jsonl_logging.h

Go to the documentation of this file.

// Copyright (c) 2023 anabrid GmbH
// Contact: https://www.anabrid.com/licensing/
// SPDX-License-Identifier: MIT OR GPL-2.0-or-later
 
#pragma once
 
#include <Arduino.h> // Output, millis()
#ifdef ARDUINO
 
#include <list>
#include <string>
 
#include "utils/print-multiplexer.h"
#include "utils/streaming_json.h"
 
namespace msg {
 
template <typename T> class ring_buffer {
  std::list<T> _data;
 
public:
  const std::list<T> &data() const { return _data; }
 
  size_t max_size; 
 
  ring_buffer(int max_size) : max_size(max_size) {}
 
  void push_back(T item) {
    if (_data.size() > max_size)
      _data.pop_front();
    _data.push_back(item);
  }
 
  void clear() { _data.clear(); }
};
 
// Decorates a stream of characters into JSONL-ready LogLines
struct StreamLogger : public Print {
  uint16_t line_count = 0;
  bool new_line = true;
  ::utils::StreamingJson target;
 
  StreamLogger(Print &_target) : target(_target) {}
 
  virtual size_t write(uint8_t b) override;
  // size_t write(const uint8_t *buffer, size_t size) override
};
 
struct Log : public Print {
  msg::StreamLogger formatter;
  utils::PrintMultiplexer sinks;
 
  Log() : formatter(sinks) {}
 
  virtual size_t write(uint8_t b) override { return formatter.write(b); }
 
  // for debugging...
  // Log() : msg::StreamLogger(Serial) {}
 
  static Log &get() {
    static Log instance;
    return instance;
  }
};
 
void activate_serial_log();
 
struct StartupLog : public Print {
  constexpr static size_t max_buf_size = 60;
  msg::ring_buffer<std::string> buf{max_buf_size};
  std::string linebuf = "";
 
  StartupLog() { linebuf.reserve(80); }
 
  bool is_active() { return buf.max_size != 0; }
 
  virtual size_t write(uint8_t b) override {
    if (b == '\r')
      return 1; // Ignore CR in CR NL
    if (b == '\n') {
      buf.push_back(linebuf);
      linebuf.clear();
      return 1;
    }
    linebuf += b;
    return 1;
  }
 
  void disable() {
    buf.max_size = 0;
    buf.clear();
    linebuf.clear();
  }
 
  // Logs are big so don't use regular ArduinoJSON
  void stream_to_json(utils::StreamingJson &s);
 
  static StartupLog &get() {
    static StartupLog instance;
    return instance;
  }
};
 
} // namespace msg
 
#endif // ARDUINO