VILLASnode/lib/formats/json_reserve.cpp

/* JSON serializtion for RESERVE project.
 *
 * Author: Steffen Vogel <post@steffenvogel.de>
 * SPDX-FileCopyrightText: 2014-2023 Institute for Automation of Complex Power Systems, RWTH Aachen University
 * SPDX-License-Identifier: Apache-2.0
 */

#include <cstring>

#include <villas/formats/json_reserve.hpp>
#include <villas/timing.hpp>

using namespace villas::node;

#define JSON_RESERVE_INTEGER_TARGET 1

int JsonReserveFormat::packSample(json_t **json_smp, const struct Sample *smp) {
  json_error_t err;
  json_t *json_root;
  json_t *json_data;
  json_t *json_name;
  json_t *json_unit;
  json_t *json_value;
  json_t *json_created = nullptr;
  json_t *json_sequence = nullptr;

  if (smp->flags & (int)SampleFlags::HAS_TS_ORIGIN)
    json_created = json_integer(time_to_double(&smp->ts.origin) * 1e3);

  if (smp->flags & (int)SampleFlags::HAS_SEQUENCE)
    json_sequence = json_integer(smp->sequence);

  json_data = json_array();

  for (unsigned i = 0; i < smp->length; i++) {
    auto sig = smp->signals->getByIndex(i);
    if (!sig)
      return -1;

    if (!sig->name.empty())
      json_name = json_string(sig->name.c_str());
    else {
      char name[32];
      snprintf(name, 32, "signal%u", i);

      json_name = json_string(name);
    }

    if (!sig->unit.empty())
      json_unit = json_string(sig->unit.c_str());
    else
      json_unit = nullptr;

    json_value = json_pack_ex(&err, 0, "{ s: o, s: f }", "name", json_name,
                              "value", smp->data[i].f);
    if (!json_value)
      continue;

    if (json_unit)
      json_object_set_new(json_value, "unit", json_unit);
    if (json_created)
      json_object_set_new(json_value, "created", json_created);
    if (json_sequence)
      json_object_set_new(json_value, "sequence", json_sequence);

    json_array_append_new(json_data, json_value);
  }

  json_root = json_pack_ex(&err, 0, "{ s: o }", "measurements", json_data);
  if (json_root == nullptr)
    return -1;
#if 0
#ifdef JSON_RESERVE_INTEGER_TARGET
	if (io->out.node) {
		char *endptr;
		char *id_str = strrchr(io->out.node->name, '_');
		if (!id_str)
			return -1;

		int id = strtoul(id_str+1, &endptr, 10);
		if (endptr[0] != 0)
			return -1;

		json_object_set_new(json_root, "target", json_integer(id));
	}
#else
	if (io->out.node)
		json_object_set_new(json_root, "target", json_string(io->out.node->name));
#endif
#endif

  *json_smp = json_root;

  return 0;
}

int JsonReserveFormat::unpackSample(json_t *json_smp, struct Sample *smp) {
  int ret, idx;
  double created = -1;
  json_error_t err;
  json_t *json_value, *json_data = nullptr;
  json_t *json_origin = nullptr, *json_target = nullptr;
  size_t i;

  ret = json_unpack_ex(json_smp, &err, 0, "{ s?: o, s?: o, s?: o, s?: o }",
                       "origin", &json_origin, "target", &json_target,
                       "measurements", &json_data, "setpoints", &json_data);
  if (ret)
    return -1;

#if 0
#ifdef JSON_RESERVE_INTEGER_TARGET
	if (json_target && io->in.node) {
		if (!json_is_integer(json_target))
			return -1;

		char *endptr;
		char *id_str = strrchr(io->in.node->name, '_');
		if (!id_str)
			return -1;

		int id = strtoul(id_str+1, &endptr, 10);
		if (endptr[0] != 0)
			return -1;

		if (id != json_integer_value(json_target))
			return 0;
	}
#else
	if (json_target && io->in.node) {
		const char *target = json_string_value(json_target);
		if (!target)
			return -1;

		if (strcmp(target, io->in.node->name))
			return 0;
	}
#endif
#endif
  if (!json_data || !json_is_array(json_data))
    return -1;

  smp->flags = 0;
  smp->length = 0;

  json_array_foreach(json_data, i, json_value) {
    const char *name, *unit = nullptr;
    double value;

    ret = json_unpack_ex(json_value, &err, 0, "{ s: s, s?: s, s: F, s?: F }",
                         "name", &name, "unit", &unit, "value", &value,
                         "created", &created);
    if (ret)
      return -1;

    auto sig = signals->getByName(name);
    if (sig)
      idx = signals->getIndexByName(name);
    else {
      ret = sscanf(name, "signal_%d", &idx);
      if (ret != 1)
        continue;
    }

    if (idx < 0)
      return -1;

    if (idx < (int)smp->capacity) {
      smp->data[idx].f = value;

      if (idx >= (int)smp->length)
        smp->length = idx + 1;
    }
  }

  if (smp->length > 0)
    smp->flags |= (int)SampleFlags::HAS_DATA;

  if (created > 0) {
    smp->ts.origin = time_from_double(created * 1e-3);
    smp->flags |= (int)SampleFlags::HAS_TS_ORIGIN;
  }

  return smp->length > 0 ? 1 : 0;
}

// Register format
static char n[] = "json.reserve";
static char d[] = "RESERVE JSON format";
static FormatPlugin<JsonReserveFormat, n, d,
                    (int)SampleFlags::HAS_TS_ORIGIN |
                        (int)SampleFlags::HAS_SEQUENCE |
                        (int)SampleFlags::HAS_DATA>
    p;