Commit afa03840 authored by Matthias Käppler's avatar Matthias Käppler 3️⃣ Committed by Bob Van Landuyt
Browse files

Reject reserved log keys in dev & test

parent 08ca2edf

lib/labkit/logging/json_logger.rb

+22 −0
Original line number Diff line number Diff line
@@ -6,6 +6,17 @@ require "json" 
module Labkit

  module Logging

    class JsonLogger < ::Logger

      INTERNAL_LOG_KEYS = Labkit::Context::RAW_KEYS + [Labkit::Context::LOG_KEY]

      RESERVED_LOG_KEYS = INTERNAL_LOG_KEYS.map(&:to_sym) + [

        :environment,

        :host,

        :shard,

        :stage,

        :subcomponent,

        :tier,

        :type,

      ].freeze



      def self.log_level(fallback: ::Logger::DEBUG)

        ENV.fetch("GITLAB_LOG_LEVEL", fallback)

      end
@@ -24,6 +35,7 @@ module Labkit 
        when String

          data[:message] = message

        when Hash

          reject_reserved_log_keys!(message)

          data.merge!(message)

        end
@@ -39,6 +51,16 @@ module Labkit 
      def dump_json(data)

        JSON.generate(data)

      end



      def reject_reserved_log_keys!(hash)

        return if ENV["RAILS_ENV"] == "production"



        reserved_keys_used = hash.transform_keys(&:to_sym).slice(*RESERVED_LOG_KEYS)

        if reserved_keys_used.any?

          raise "The following log keys used are reserved: #{reserved_keys_used.keys.join(", ")}" +

                  "\n\nUse key names that are descriptive e.g. by using a prefix."

        end

      end

    end

  end

end

spec/labkit/logging/json_logger_spec.rb

+51 −0
Original line number Diff line number Diff line
@@ -120,4 +120,55 @@ RSpec.describe Labkit::Logging::JsonLogger do 
    expect(data["message"]).to be_nil

    expect(data["correlation_id"]).to eq("new-correlation-id")

  end



  it "uses indifferent log key access" do

    output = subject.format_message("INFO", now, "test", { hello: 1, "world": 2 })

    data = JSON.parse(output)



    expect(data["hello"]).to eq(1)

    expect(data["world"]).to eq(2)

  end



  describe "reserved log keys" do

    let(:reserved_key_data) { described_class::RESERVED_LOG_KEYS.to_h { |k| [k, 42] } }

    let(:expected_error) { /^The following log keys used are reserved: #{described_class::RESERVED_LOG_KEYS.join(", ")}.*/ }



    shared_examples "raise error" do

      it "raises an error" do

        expect { subject.format_message("INFO", now, "test", reserved_key_data) }.to raise_error(expected_error)

      end



      describe "symbol and string indifference" do

        it "raises error when reserved key is a symbol" do

          expect { subject.format_message("INFO", now, "test", reserved_key_data.transform_keys(&:to_sym)) }.to raise_error(expected_error)

        end



        it "raises error when reserved key is a string" do

          expect { subject.format_message("INFO", now, "test", reserved_key_data.transform_keys(&:to_s)) }.to raise_error(expected_error)

        end

      end

    end



    describe "in test env" do

      it_behaves_like "raise error"

    end



    describe "in dev env" do

      before do

        stub_env("RAILS_ENV", "development")

      end



      it_behaves_like "raise error"

    end



    describe "in production env" do

      before do

        stub_env("RAILS_ENV", "production")

      end



      it "does not raise an error" do

        expect { subject.format_message("INFO", now, "test", reserved_key_data) }.not_to raise_error

      end

    end

  end

end