Module: GraphQL::Tracing::PerfettoTrace

Defined in:
lib/graphql/tracing/perfetto_trace.rb,
lib/graphql/tracing/perfetto_trace/trace_pb.rb

Overview

This produces a trace file for inspecting in the Perfetto Trace Viewer.

To get the file, call #write on the trace.

Use “trace modes” to configure this to run on command or on a sample of traffic.

Examples:

Writing trace output


result = MySchema.execute(...)
result.query.trace.write(file: "tmp/trace.dump")

Running this instrumenter when trace: true is present in the request


class MySchema < GraphQL::Schema
  # Only run this tracer when `context[:trace_mode]` is `:trace`
  trace_with GraphQL::Tracing::Perfetto, mode: :trace
end

# In graphql_controller.rb:

context[:trace_mode] = params[:trace] ? :trace : nil
result = MySchema.execute(query_str, context: context, variables: variables, ...)
if context[:trace_mode] == :trace
  result.trace.write(file: ...)
end

Constant Summary collapse

PROTOBUF_AVAILABLE =

TODOs: - Make debug annotations visible on both parts when dataloader is involved

begin
  require "google/protobuf"
  true
rescue LoadError
  false
end
DATALOADER_CATEGORY_IIDS = 
[5]
FIELD_EXECUTE_CATEGORY_IIDS = 
[6]
ACTIVE_SUPPORT_NOTIFICATIONS_CATEGORY_IIDS = 
[7]
AUTHORIZED_CATEGORY_IIDS = 
[8]
RESOLVE_TYPE_CATEGORY_IIDS = 
[9]
DA_OBJECT_IID = 
10
DA_RESULT_IID = 
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DA_ARGUMENTS_IID = 
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DA_FETCH_KEYS_IID = 
13
DA_STR_VAL_NIL_IID = 
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Trace = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.Trace").msgclass
TracePacket = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.TracePacket").msgclass
TrackEvent = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.TrackEvent").msgclass
DebugAnnotation = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.DebugAnnotation").msgclass
TrackDescriptor = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.TrackDescriptor").msgclass
CounterDescriptor = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.CounterDescriptor").msgclass
InternedData = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.InternedData").msgclass
InternedString = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.InternedString").msgclass
EventCategory = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.EventCategory").msgclass
EventName = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.EventName").msgclass
DebugAnnotationName = 
::Google::Protobuf::DescriptorPool.generated_pool.lookup("perfetto_trace.protos.DebugAnnotationName").msgclass

Instance Method Summary collapse

Instance Method Details

#begin_analyze_multiplex(m, analyzers) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 239

def begin_analyze_multiplex(m, analyzers)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_BEGIN,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
    name: "Analysis",
    debug_annotations: [
      payload_to_debug("analyzers_count", analyzers.size),
      payload_to_debug("analyzers", analyzers),
    ]
  )
  super
end

#begin_authorized(type, obj, ctx) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 449

def begin_authorized(type, obj, ctx)
  packet = trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_BEGIN,
    track_uuid: fid,
    category_iids: AUTHORIZED_CATEGORY_IIDS,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
    name_iid: @auth_name_iids[type],
  )
  @packets << packet
  fiber_flow_stack << packet
  super
end

#begin_dataloader(dl) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 394

def begin_dataloader(dl)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_COUNTER,
    track_uuid: @fibers_counter_id,
    counter_value: count_fibers(1),
  )
  @did = fid
  @packets << track_descriptor_packet(@main_fiber_id, @did, "Dataloader Fiber ##{@did}")
  super
end

#begin_dataloader_source(source) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 414

def begin_dataloader_source(source)
  fds = @flow_ids[source]
  fds_copy = fds.dup
  fds.clear
  packet = trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_BEGIN,
    track_uuid: fid,
    name_iid: @source_name_iids[source.class],
    category_iids: DATALOADER_CATEGORY_IIDS,
    flow_ids: fds_copy,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
    debug_annotations: [
      payload_to_debug(nil, source.pending.values, iid: DA_FETCH_KEYS_IID, intern_value: true),
      *(source.instance_variables - [:@pending, :@fetching, :@results, :@dataloader]).map { |iv|
        payload_to_debug(iv.to_s, source.instance_variable_get(iv), intern_value: true)
      }
    ]
  )
  @packets << packet
  fiber_flow_stack << packet
  super
end

#begin_execute_field(field, object, arguments, query) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 206

def begin_execute_field(field, object, arguments, query)
  packet = trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_BEGIN,
    track_uuid: fid,
    name: query.context.current_path.join("."),
    category_iids: FIELD_EXECUTE_CATEGORY_IIDS,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
  )
  @packets << packet
  fiber_flow_stack << packet
  super
end

#begin_resolve_type(type, value, context) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 475

def begin_resolve_type(type, value, context)
  packet = trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_BEGIN,
    track_uuid: fid,
    category_iids: RESOLVE_TYPE_CATEGORY_IIDS,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
    name_iid: @resolve_type_name_iids[type],
  )
  @packets << packet
  fiber_flow_stack << packet
  super
end

#begin_validate(query, validate) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 282

def begin_validate(query, validate)
  @packets << @begin_validate = trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_BEGIN,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
    name: "Validate",
    debug_annotations: [
      payload_to_debug("validate?", validate),
    ]
  )
  super
end

#dataloader_fiber_exit ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 382

def dataloader_fiber_exit
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_INSTANT,
    track_uuid: fid,
    name: "Fiber Exit",
    category_iids: DATALOADER_CATEGORY_IIDS,
    extra_counter_track_uuids: [@fibers_counter_id],
    extra_counter_values: [count_fibers(-1)],
  )
  super
end

#dataloader_fiber_resume(source) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 363

def dataloader_fiber_resume(source)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_INSTANT,
    track_uuid: fid,
    name: "Fiber Resume",
    category_iids: DATALOADER_CATEGORY_IIDS,
  )

  ls = fiber_flow_stack.pop
  @packets << packet = TracePacket.new(
    timestamp: ts,
    track_event: dup_with(ls.track_event, { type: TrackEvent::Type::TYPE_SLICE_BEGIN }),
    trusted_packet_sequence_id: @sequence_id,
  )
  fiber_flow_stack << packet

  super
end

#dataloader_fiber_yield(source) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 341

def dataloader_fiber_yield(source)
  ls = fiber_flow_stack.last
  if (flow_id = ls.track_event.flow_ids.first)
    # got it
  else
    flow_id = ls.track_event.name.object_id
    ls.track_event = dup_with(ls.track_event, {flow_ids: [flow_id] }, delete_counters: true)
  end
  @flow_ids[source] << flow_id
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
  )
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_INSTANT,
    track_uuid: fid,
    name: "Fiber Yield",
    category_iids: DATALOADER_CATEGORY_IIDS,
  )
  super
end

#dataloader_spawn_execution_fiber(jobs) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 315

def dataloader_spawn_execution_fiber(jobs)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_INSTANT,
    track_uuid: fid,
    name: "Create Execution Fiber",
    category_iids: DATALOADER_CATEGORY_IIDS,
    extra_counter_track_uuids: [@fibers_counter_id, @objects_counter_id],
    extra_counter_values: [count_fibers(1), count_allocations]
  )
  @packets << track_descriptor_packet(@did, fid, "Exec Fiber ##{fid}")
  super
end

#dataloader_spawn_source_fiber(pending_sources) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 328

def dataloader_spawn_source_fiber(pending_sources)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_INSTANT,
    track_uuid: fid,
    name: "Create Source Fiber",
    category_iids: DATALOADER_CATEGORY_IIDS,
    extra_counter_track_uuids: [@fibers_counter_id, @objects_counter_id],
    extra_counter_values: [count_fibers(1), count_allocations]
  )
  @packets << track_descriptor_packet(@did, fid, "Source Fiber ##{fid}")
  super
end

#end_analyze_multiplex(m, analyzers) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 254

def end_analyze_multiplex(m, analyzers)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
  )
  super
end

#end_authorized(type, obj, ctx, is_authorized) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 463

def end_authorized(type, obj, ctx, is_authorized)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
  )
  beg_auth = fiber_flow_stack.pop
  beg_auth.track_event = dup_with(beg_auth.track_event, { debug_annotations: [payload_to_debug("authorized?", is_authorized)] })
  super
end

#end_dataloader(dl) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 405

def end_dataloader(dl)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_COUNTER,
    track_uuid: @fibers_counter_id,
    counter_value: count_fibers(-1),
  )
  super
end

#end_dataloader_source(source) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 438

def end_dataloader_source(source)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
  )
  fiber_flow_stack.pop
  super
end

#end_execute_field(field, object, arguments, query, app_result) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 220

def end_execute_field(field, object, arguments, query, app_result)
  start_field = fiber_flow_stack.pop
  start_field.track_event = dup_with(start_field.track_event, {
    debug_annotations: [
      payload_to_debug(nil, object.object, iid: DA_OBJECT_IID, intern_value: true),
      payload_to_debug(nil, arguments, iid: DA_ARGUMENTS_IID),
      payload_to_debug(nil, app_result, iid: DA_RESULT_IID, intern_value: true)
    ]
  })

  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id, @fields_counter_id],
    extra_counter_values: [count_allocations, count_fields],
  )
  super
end

#end_resolve_type(type, value, context, resolved_type) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 489

def end_resolve_type(type, value, context, resolved_type)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
  )
  rt_begin = fiber_flow_stack.pop
  rt_begin.track_event = dup_with(rt_begin.track_event, { debug_annotations: [payload_to_debug("resolved_type", resolved_type, intern_value: true)] })
  super
end

#end_validate(query, validate, validation_errors) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 296

def end_validate(query, validate, validation_errors)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
  )
  @begin_validate.track_event = dup_with(
    @begin_validate.track_event,
    {
      debug_annotations: [
        @begin_validate.track_event.debug_annotations.first,
        payload_to_debug("valid?", validation_errors.empty?)
      ]
    }
  )
  super
end

#execute_multiplex(multiplex:) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 174

def execute_multiplex(multiplex:)
  if defined?(ActiveSupport::Notifications) && @active_support_notifications_pattern != false
    subscribe_to_active_support_notifications(@active_support_notifications_pattern)
  end
  @operation_name = multiplex.queries.map { |q| q.selected_operation_name || "anonymous" }.join(",")
  @begin_time = Time.now
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_BEGIN,
    track_uuid: fid,
    name: "Multiplex",
    debug_annotations: [
      payload_to_debug("query_string", multiplex.queries.map(&:sanitized_query_string).join("\n\n"))
    ]
  )
  result = super

  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
  )

  result
ensure
  unsubscribe_from_active_support_notifications
  if @save_profile
    begin_ts = (@begin_time.to_f * 1000).round
    end_ts = (Time.now.to_f * 1000).round
    duration_ms = end_ts - begin_ts
    multiplex.schema.detailed_trace.save_trace(@operation_name, duration_ms, begin_ts, Trace.encode(Trace.new(packet: @packets)))
  end
end

#initialize(active_support_notifications_pattern: nil, save_profile: false, **_rest) ⇒ Object

Parameters:

  • active_support_notifications_pattern (String, RegExp, false) (defaults to: nil) —

    A filter for ActiveSupport::Notifications, if it’s present. Or false to skip subscribing.



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 64

def initialize(active_support_notifications_pattern: nil, save_profile: false, **_rest)
  super
  @active_support_notifications_pattern = active_support_notifications_pattern
  @save_profile = save_profile
  Fiber[:graphql_flow_stack] = nil
  @sequence_id = object_id
  @pid = Process.pid
  @flow_ids = Hash.new { |h, source_inst| h[source_inst] = [] }.compare_by_identity
  @new_interned_event_names = {}
  @interned_event_name_iids = Hash.new { |h, k|
    new_id = 100 + h.size
    @new_interned_event_names[k] = new_id
    h[k] = new_id
  }

  @source_name_iids = Hash.new do |h, source_class|
    h[source_class] = @interned_event_name_iids[source_class.name]
  end.compare_by_identity

  @auth_name_iids = Hash.new do |h, graphql_type|
    h[graphql_type] = @interned_event_name_iids["Authorize: #{graphql_type.graphql_name}"]
  end.compare_by_identity

  @resolve_type_name_iids = Hash.new do |h, graphql_type|
    h[graphql_type] = @interned_event_name_iids["Resolve Type: #{graphql_type.graphql_name}"]
  end.compare_by_identity

  @new_interned_da_names = {}
  @interned_da_name_ids = Hash.new { |h, k|
    next_id = 100 + h.size
    @new_interned_da_names[k] = next_id
    h[k] = next_id
  }

  @new_interned_da_string_values = {}
  @interned_da_string_values = Hash.new do |h, k|
    new_id = 100 + h.size
    @new_interned_da_string_values[k] = new_id
    h[k] = new_id
  end

  @class_name_iids = Hash.new do |h, k|
    h[k] = @interned_da_string_values[k.name]
  end.compare_by_identity

  @starting_objects = GC.stat(:total_allocated_objects)
  @objects_counter_id = :objects_counter.object_id
  @fibers_counter_id = :fibers_counter.object_id
  @fields_counter_id = :fields_counter.object_id
  @begin_validate = nil
  @begin_time = nil
  @packets = []
  @packets << TracePacket.new(
    track_descriptor: TrackDescriptor.new(
      uuid: tid,
      name: "Main Thread",
      child_ordering: TrackDescriptor::ChildTracksOrdering::CHRONOLOGICAL,
    ),
    first_packet_on_sequence: true,
    previous_packet_dropped: true,
    trusted_packet_sequence_id: @sequence_id,
    sequence_flags: 3,
  )
  @packets << TracePacket.new(
    interned_data: InternedData.new(
      event_categories: [
        EventCategory.new(name: "Dataloader", iid: DATALOADER_CATEGORY_IIDS.first),
        EventCategory.new(name: "Field Execution", iid: FIELD_EXECUTE_CATEGORY_IIDS.first),
        EventCategory.new(name: "ActiveSupport::Notifications", iid: ACTIVE_SUPPORT_NOTIFICATIONS_CATEGORY_IIDS.first),
        EventCategory.new(name: "Authorized", iid: AUTHORIZED_CATEGORY_IIDS.first),
        EventCategory.new(name: "Resolve Type", iid: RESOLVE_TYPE_CATEGORY_IIDS.first),
      ],
      debug_annotation_names: [
        DebugAnnotationName.new(name: "object", iid: DA_OBJECT_IID),
        DebugAnnotationName.new(name: "arguments", iid: DA_ARGUMENTS_IID),
        DebugAnnotationName.new(name: "result", iid: DA_RESULT_IID),
        DebugAnnotationName.new(name: "fetch keys", iid: DA_FETCH_KEYS_IID),
      ],
      debug_annotation_string_values: [
        InternedString.new(str: "(nil)", iid: DA_STR_VAL_NIL_IID),
      ],
    ),
    trusted_packet_sequence_id: @sequence_id,
    sequence_flags: 2,
  )
  @main_fiber_id = fid
  @packets << track_descriptor_packet(tid, fid, "Main Fiber")
  @packets << track_descriptor_packet(tid, @objects_counter_id, "Allocated Objects", counter: {})
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_COUNTER,
    track_uuid: @objects_counter_id,
    counter_value: count_allocations,
  )
  @packets << track_descriptor_packet(tid, @fibers_counter_id, "Active Fibers", counter: {})
  @fibers_count = 0
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_COUNTER,
    track_uuid: @fibers_counter_id,
    counter_value: count_fibers(0),
  )

  @packets << track_descriptor_packet(tid, @fields_counter_id, "Resolved Fields", counter: {})
  @fields_count = -1
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_COUNTER,
    track_uuid: @fields_counter_id,
    counter_value: count_fields,
  )
end

#parse(query_string:) ⇒ Object 



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 264

def parse(query_string:)
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_BEGIN,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
    name: "Parse"
  )
  result = super
  @packets << trace_packet(
    type: TrackEvent::Type::TYPE_SLICE_END,
    track_uuid: fid,
    extra_counter_track_uuids: [@objects_counter_id],
    extra_counter_values: [count_allocations],
  )
  result
end

#write(file:, debug_json: false) ⇒ nil, ...

Dump protobuf output in the specified file.

Parameters:

  • file (String) —

    path to a file in a directory that already exists

  • debug_json (Boolean) (defaults to: false) —

    True to print JSON instead of binary

Returns:

  • (nil, String, Hash) —

    If file was given, nil. If file was nil, a Hash if debug_json: true, else binary data.



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# File 'lib/graphql/tracing/perfetto_trace.rb', line 505

def write(file:, debug_json: false)
  trace = Trace.new(
    packet: @packets,
  )
  data = if debug_json
    small_json = Trace.encode_json(trace)
    JSON.pretty_generate(JSON.parse(small_json))
  else
    Trace.encode(trace)
  end

  if file
    File.write(file, data, mode: 'wb')
    nil
  else
    data
  end
end