1 files changed, 285 insertions, 0 deletions
diff --git a/mocktracer/src/json.cpp b/mocktracer/src/json.cpp
new file mode 100644
index 0000000..10c46d3
--- /dev/null
+++ b/mocktracer/src/json.cpp
@@ -0,0 +1,285 @@
+#include <opentracing/mocktracer/json.h>
+#include <opentracing/mocktracer/recorder.h>
+#include <opentracing/string_view.h>
+#include <cmath>
+#include <iomanip>
+#include <sstream>
+
+namespace opentracing {
+BEGIN_OPENTRACING_ABI_NAMESPACE
+namespace mocktracer {
+// The implementation is based off of this answer from StackOverflow:
+// https://stackoverflow.com/a/33799784
+static void WriteEscapedString(std::ostream& writer,
+                               opentracing::string_view s) {
+  writer << '"';
+  for (char c : s) {
+    switch (c) {
+      case '"':
+        writer << R"(\")";
+        break;
+      case '\\':
+        writer << R"(\\)";
+        break;
+      case '\b':
+        writer << R"(\b)";
+        break;
+      case '\n':
+        writer << R"(\n)";
+        break;
+      case '\r':
+        writer << R"(\r)";
+        break;
+      case '\t':
+        writer << R"(\t)";
+        break;
+      default:
+        if ('\x00' <= c && c <= '\x1f') {
+          writer << R"(\u)";
+          writer << std::hex << std::setw(4) << std::setfill('0')
+                 << static_cast<int>(c);
+        } else {
+          writer << c;
+        }
+    }
+  }
+  writer << '"';
+}
+
+static void WriteId(std::ostream& writer, uint64_t id) {
+  std::ostringstream oss;
+  oss << std::setfill('0') << std::setw(16) << std::hex << id;
+  if (!oss.good()) {
+    writer.setstate(std::ios::failbit);
+    return;
+  }
+  writer << '"' << oss.str() << '"';
+}
+
+static void ToJson(std::ostream& writer,
+                   const SpanContextData& span_context_data) {
+  writer << '{';
+  writer << R"("trace_id":)";
+  WriteId(writer, span_context_data.trace_id);
+  writer << ',';
+
+  writer << R"("span_id":)";
+  WriteId(writer, span_context_data.span_id);
+  writer << ',';
+
+  writer << R"("baggage":{)";
+  auto num_baggage = span_context_data.baggage.size();
+  size_t baggage_index = 0;
+  for (auto& baggage_item : span_context_data.baggage) {
+    WriteEscapedString(writer, baggage_item.first);
+    writer << ':';
+    WriteEscapedString(writer, baggage_item.second);
+    if (++baggage_index < num_baggage) {
+      writer << ',';
+    }
+  }
+  writer << '}';
+  writer << '}';
+}
+
+static void ToJson(std::ostream& writer,
+                   const SpanReferenceData& span_reference_data) {
+  writer << '{';
+  writer << R"("reference_type":)";
+  if (span_reference_data.reference_type == SpanReferenceType::ChildOfRef) {
+    writer << R"("CHILD_OF")";
+  } else {
+    writer << R"("FOLLOWS_FROM")";
+  }
+  writer << ',';
+
+  writer << R"("trace_id":)";
+  WriteId(writer, span_reference_data.trace_id);
+  writer << ',';
+  writer << R"("span_id":)";
+  WriteId(writer, span_reference_data.span_id);
+
+  writer << '}';
+}
+
+static void ToJson(std::ostream& writer, const Value& value);
+
+namespace {
+struct ValueVisitor {
+  std::ostream& writer;
+
+  void operator()(bool value) {
+    if (value) {
+      writer << "true";
+    } else {
+      writer << "false";
+    }
+  }
+
+  void operator()(double value) {
+    if (std::isnan(value)) {
+      writer << R"("NaN")";
+    } else if (std::isinf(value)) {
+      if (std::signbit(value)) {
+        writer << R"("-Inf")";
+      } else {
+        writer << R"("+Inf")";
+      }
+    } else {
+      writer << value;
+    }
+  }
+
+  void operator()(int64_t value) { writer << value; }
+
+  void operator()(uint64_t value) { writer << value; }
+
+  void operator()(const std::string& s) { WriteEscapedString(writer, s); }
+
+  void operator()(std::nullptr_t) { writer << "null"; }
+
+  void operator()(const char* s) { WriteEscapedString(writer, s); }
+
+  void operator()(const Values& values) {
+    writer << '[';
+    size_t i = 0;
+    for (const auto& value : values) {
+      ToJson(writer, value);
+      if (++i < values.size()) {
+        writer << ',';
+      }
+    }
+    writer << ']';
+  }
+
+  void operator()(const Dictionary& dictionary) {
+    writer << '{';
+    size_t i = 0;
+    for (const auto& key_value : dictionary) {
+      WriteEscapedString(writer, key_value.first);
+      writer << ':';
+      ToJson(writer, key_value.second);
+      if (++i < dictionary.size()) {
+        writer << ',';
+      }
+    }
+    writer << '}';
+  }
+};
+}  // anonymous namespace
+
+void ToJson(std::ostream& writer, const Value& value) {
+  ValueVisitor value_visitor{writer};
+  apply_visitor(value_visitor, value);
+}
+
+template <class Rep, class Period>
+static void ToJson(std::ostream& writer,
+                   const std::chrono::duration<Rep, Period>& duration) {
+  auto count =
+      std::chrono::duration_cast<std::chrono::microseconds>(duration).count();
+  writer << count;
+}
+
+static void ToJson(std::ostream& writer, const LogRecord& log_record) {
+  writer << '{';
+  writer << R"("timestamp":)";
+  ToJson(writer, log_record.timestamp.time_since_epoch());
+  writer << ',';
+  writer << R"("fields":)";
+  writer << '[';
+  auto num_fields = log_record.fields.size();
+  size_t field_index = 0;
+  for (auto& field : log_record.fields) {
+    writer << '{';
+    writer << R"("key":)";
+    WriteEscapedString(writer, field.first);
+    writer << ',';
+    writer << R"("value":)";
+    ToJson(writer, field.second);
+    writer << '}';
+    if (++field_index < num_fields) {
+      writer << ',';
+    }
+  }
+  writer << ']';
+  writer << '}';
+}
+
+static void ToJson(std::ostream& writer, const SpanData& span_data) {
+  writer << '{';
+
+  writer << R"("span_context":)";
+  ToJson(writer, span_data.span_context);
+  writer << ',';
+
+  writer << R"("references":)";
+  writer << '[';
+  auto num_references = span_data.references.size();
+  size_t reference_index = 0;
+  for (auto& reference : span_data.references) {
+    ToJson(writer, reference);
+    if (++reference_index < num_references) {
+      writer << ',';
+    }
+  }
+  writer << ']';
+  writer << ',';
+
+  writer << R"("operation_name":)";
+  WriteEscapedString(writer, span_data.operation_name);
+  writer << ',';
+
+  writer << R"("start_timestamp":)";
+  ToJson(writer, span_data.start_timestamp.time_since_epoch());
+  writer << ',';
+
+  writer << R"("duration":)";
+  ToJson(writer, span_data.duration);
+  writer << ',';
+
+  writer << R"("tags":)";
+  writer << '{';
+  auto num_tags = span_data.tags.size();
+  size_t tag_index = 0;
+  for (auto& tag : span_data.tags) {
+    WriteEscapedString(writer, tag.first);
+    writer << ':';
+    ToJson(writer, tag.second);
+    if (++tag_index < num_tags) {
+      writer << ',';
+    }
+  }
+  writer << '}';
+  writer << ',';
+
+  writer << R"("logs":)";
+  writer << '[';
+  auto num_logs = span_data.logs.size();
+  size_t log_index = 0;
+  for (auto& log : span_data.logs) {
+    ToJson(writer, log);
+    if (++log_index < num_logs) {
+      writer << ',';
+    }
+  }
+  writer << ']';
+
+  writer << '}';
+}
+
+void ToJson(std::ostream& writer, const std::vector<SpanData>& spans) {
+  writer << '[';
+  auto num_spans = spans.size();
+  size_t span_index = 0;
+  for (auto& span_data : spans) {
+    ToJson(writer, span_data);
+    if (++span_index < num_spans) {
+      writer << ',';
+    }
+  }
+  writer << ']';
+}
+}  // namespace mocktracer
+END_OPENTRACING_ABI_NAMESPACE
+}  // namespace opentracing