make export logger

exporter/otlp-logs/lib/opentelemetry/exporter/otlp/logs_exporter.rb

@@ -70,6 +70,16 @@ def initialize(endpoint: OpenTelemetry::Common::Utilities.config_opt('OTEL_EXPOR
           @timeout = timeout.to_f
           @compression = compression
           @shutdown = false
+          @logger = create_logger
+        end
+
+        def create_logger
+          logger = Logger.new($stdout, level: ENV['OTEL_LOG_LEVEL'] || Logger::INFO)
+          # @skip_instrumenting prevents Ruby Logger instrumentation from
+          # triggering a stack overflow. Logs emitted using OpenTelemetry.logger
+          # will not be turned into OpenTelemetry LogRecords.
+          logger.instance_variable_set(:@skip_instrumenting, true)
+          logger
         end
 
         # Called to export sampled {OpenTelemetry::SDK::Logs::LogRecordData} structs.
@@ -128,11 +138,11 @@ def around_request
         end
 
         def send_bytes(bytes, timeout:) # rubocop:disable Metrics/CyclomaticComplexity, Metrics/MethodLength, Metrics/PerceivedComplexity
-          logger.error("From Logs exporter: bytes.nil? #{bytes.nil?}")
+          @logger.error("From Logs exporter: bytes.nil? #{bytes.nil?}")
           return FAILURE if bytes.nil?
 
-          logger.error("LOGZ: path - #{@path}")
-          logger.error("LOGZ: compression - #{@compression}")
+          @logger.error("LOGZ: path - #{@path}")
+          @logger.error("LOGZ: compression - #{@compression}")
           request = Net::HTTP::Post.new(@path)
           if @compression == 'gzip'
             request.add_field('Content-Encoding', 'gzip')
@@ -159,7 +169,7 @@ def send_bytes(bytes, timeout:) # rubocop:disable Metrics/CyclomaticComplexity,
             @http.start unless @http.started?
             response = measure_request_duration { @http.request(request) }
 
-            logger.error("LOGZ response: #{response}")
+            @logger.error("LOGZ response: #{response}")
             case response
             when Net::HTTPOK
               response.body # Read and discard body
@@ -266,7 +276,7 @@ def backoff?(retry_count:, reason:, retry_after: nil) # rubocop:disable Metrics/
         end
 
         def encode(log_record_data) # rubocop:disable Metrics/MethodLength, Metrics/CyclomaticComplexity
-          logger.error("Logs exporter made it to encode!")
+          @logger.error("Logs exporter made it to encode!")
           Opentelemetry::Proto::Collector::Logs::V1::ExportLogsServiceRequest.encode(
             Opentelemetry::Proto::Collector::Logs::V1::ExportLogsServiceRequest.new(
               resource_logs: log_record_data