Add runtime context to log events (#3)

* ✨ Add file, line, and frame label to runtime context

* 💚 Fix existing tests

* ✅ Add test for runtime context

* 💄

* 🚧

* 👀

* 👀

* 👀

* 👀

* 👀

* 💚

* 💚

* 🚧 Improve gem installation path detection

* 🚧 Account for older ruby versions

* 🚧 Detect all logtail gems

* 🚧 Change the regex

* ✅ Update tests

* Update lib/logtail/log_entry.rb

Co-authored-by: Tomáš Hromada <[email protected]>

* Revert "Update lib/logtail/log_entry.rb"

This reverts commit 636f93c.

Co-authored-by: Tomáš Hromada <[email protected]>

Author: simonrozsival

lib/logtail/log_entry.rb

@@ -1,5 +1,6 @@
 require "socket"
 require "time"
+require "pathname"
 
 require "logtail/contexts"
 require "logtail/events"
@@ -11,6 +12,7 @@ class LogEntry #:nodoc:
     BINARY_LIMIT_THRESHOLD = 1_000.freeze
     DT_PRECISION = 6.freeze
     MESSAGE_MAX_BYTES = 8192.freeze
+    LOGTAIL_GEM_REGEX = /\/logtail(?:-ruby|-rails|-rack)?(?:-\d+(?:\.\d+)*)?\/lib$/.freeze
 
     attr_reader :context_snapshot, :event, :level, :message, :progname, :tags, :time
 
@@ -45,7 +47,7 @@ def to_hash(options = {})
       hash = {
         :level => level,
         :dt => formatted_dt,
-        :message => message
+        :message => message,
       }
 
       if !tags.nil? && tags.length > 0
@@ -60,6 +62,10 @@ def to_hash(options = {})
         hash[:context] = context_snapshot
       end
 
+      hash[:context] ||= {}
+      hash[:context][:runtime] ||= {}
+      hash[:context][:runtime].merge!(current_runtime_context || {})
+
       if options[:only]
         hash.select do |key, _value|
           options[:only].include?(key)
@@ -106,5 +112,34 @@ def encode_string(string)
       rescue Exception
         nil
       end
+
+      def current_runtime_context
+        index = caller_locations.rindex { |x| logtail_frame?(x) }
+        frame = caller_locations[index + 1] unless index.nil?
+        return convert_to_runtime_context(frame) unless frame.nil?
+      end
+
+      def convert_to_runtime_context(frame)
+        {
+          file: relative_to_main_module(frame.absolute_path),
+          line: frame.lineno,
+          frame_label: frame.label,
+        }
+      end
+
+      def logtail_frame?(frame)
+        return false if frame.absolute_path.nil? || logtail_gem_paths.empty?
+        logtail_gem_paths.any? { |path| frame.absolute_path.start_with?(path) }
+      end
+
+      def logtail_gem_paths
+        @logtail_gem_paths ||= $LOAD_PATH.select { |path| path.match(LOGTAIL_GEM_REGEX) }
+      end
+
+      def relative_to_main_module(path)
+        base_file = caller_locations.last.absolute_path
+        base_path = Pathname.new(File.dirname(base_file || '/'))
+        Pathname.new(path).relative_path_from(base_path).to_s
+      end
   end
 end

spec/logtail/log_devices/http_spec.rb

@@ -102,7 +102,7 @@
       request_queue = http.instance_variable_get(:@request_queue)
       request_attempt = request_queue.deq
       expect(request_attempt.request).to be_kind_of(Net::HTTP::Post)
-      expect(request_attempt.request.body).to start_with("\x92\x83\xA5level\xA4INFO\xA2dt\xBB2016-09-01T12:00:00.000000Z\xA7message\xB2test log message 1".force_encoding("ASCII-8BIT"))
+      expect(request_attempt.request.body).to start_with("\x92\x84\xA5level\xA4INFO\xA2dt\xBB2016-09-01T12:00:00.000000Z\xA7message\xB2test log message 1".force_encoding("ASCII-8BIT"))
 
       message_queue = http.instance_variable_get(:@msg_queue)
       expect(message_queue.size).to eq(0)
@@ -127,7 +127,7 @@
     it "should deliver requests on an interval" do
       stub = stub_request(:post, "https://in.logtail.com/").
         with(
-          :body => start_with("\x92\x83\xA5level\xA4INFO\xA2dt\xBB2016-09-01T12:00:00.000000Z\xA7message\xB2test log message 1".force_encoding("ASCII-8BIT")),
+          :body => start_with("\x92\x84\xA5level\xA4INFO\xA2dt\xBB2016-09-01T12:00:00.000000Z\xA7message\xB2test log message 1".force_encoding("ASCII-8BIT")),
           :headers => {
             'Authorization' => 'Bearer MYKEY',
             'Content-Type' => 'application/msgpack',

spec/logtail/log_entry_spec.rb

@@ -19,4 +19,18 @@
       expect(msgpack).to start_with("\x85\xA5level\xA4INFO\xA2dt\xBB2016-09-01T12:00:00.000000Z".force_encoding("ASCII-8BIT"))
     end
   end
+
+  describe "#to_hash" do
+    it "should include runtime context information" do
+      $:.unshift(File.expand_path(__dir__ + '/../../lib'))
+
+      log_entry = described_class.new("INFO", time, nil, "log message", {}, {})
+      hash = log_entry.to_hash
+      expect(hash[:context]).to_not be_nil
+      expect(hash[:context][:runtime]).to_not be_nil
+      expect(hash[:context][:runtime][:file]).to_not be_nil
+      expect(hash[:context][:runtime][:line]).to_not be_nil
+      expect(hash[:context][:runtime][:frame_label]).to_not be_nil
+    end
+  end
 end