Limit each log line length

.github/workflows/test.yml

@@ -24,8 +24,6 @@ jobs:
         run: bundle exec ci-helper CheckSpecSuffixes --extra-paths spec/*.rb --ignored-paths spec/*_helper.rb
       - name: Run specs
         run: bundle exec ci-helper RunSpecs
-      - name: Audit
-        run: bundle exec ci-helper BundlerAudit
       - name: Documentation coverage
         run: bundle exec rake doc:coverage
       - name: Coveralls

Changelog.md

@@ -1,3 +1,9 @@
+# Changelog
+
+## 1.11.0
+
+* Add `max_log_length` to limit each log line length in order to prevent memory leaks in case of very long logs
+
 ## 1.10.0
 
 * Add an ability to insert Lamian's middleware inside the rails initialization process manually (`Lamian.config.middleware_autoset = true/false`)
@@ -14,7 +20,7 @@
 
 ## 1.3.0
 
-* Add support for the (new sentry gem)[https://github.com/getsentry/sentry-ruby].
+* Add support for the [new sentry gem](https://github.com/getsentry/sentry-ruby).
 
 ## 1.2.0
 
@@ -33,7 +39,6 @@ which ruins concept of single entry point :(. Also tied it to lamian instance
 
 * `8136689` fixed crashes when dump used outside lamian context
 
-
 ## 0.3.2
 
 * `e57e6cec` Changed rails dependency from `~> 4.2` to `>= 4.2`

Gemfile

@@ -5,7 +5,6 @@ source "https://rubygems.org"
 # Specify your gem's dependencies in lamian.gemspec
 gemspec
 
-gem "bundler-audit"
 gem "ci-helper"
 gem "launchy"
 gem "pry"

Gemfile.lock

@@ -83,9 +83,6 @@ GEM
     base64 (0.2.0)
     bigdecimal (3.1.8)
     builder (3.3.0)
-    bundler-audit (0.9.1)
-      bundler (>= 1.2.0, < 3)
-      thor (~> 1.0)
     childprocess (5.1.0)
       logger (~> 1.5)
     ci-helper (0.6.0)
@@ -312,7 +309,6 @@ PLATFORMS
   x86_64-linux
 
 DEPENDENCIES
-  bundler-audit
   ci-helper
   lamian!
   launchy

lib/lamian/config.rb

@@ -13,12 +13,14 @@ module Lamian
   Config = Struct.new(
     :formatter,
     :max_log_lines,
+    :max_log_length,
     :raven_log_size_limit,
     :middleware_autoset,
   ) do
     def initialize
       self.formatter = ::Logger::Formatter.new
       self.max_log_lines = 5000
+      self.max_log_length = 10_000
       self.raven_log_size_limit = 500_000
       self.middleware_autoset = true
     end

lib/lamian/log_device.rb

@@ -2,14 +2,16 @@
 
 module Lamian
   class LogDevice # :nodoc:
-    def initialize(size = Lamian.config.max_log_lines)
-      self.size = size
+    def initialize(max_log_lines: Lamian.config.max_log_lines,
+                   max_log_length: Lamian.config.max_log_length)
+      self.max_log_lines = max_log_lines
+      self.max_log_length = max_log_length
       self.lines = []
     end
 
-    def write(string) # :nodoc:
-      lines << string
-      lines.shift if lines.size > size
+    def write(msg) # :nodoc:
+      lines << truncate(msg)
+      lines.shift if lines.size > max_log_lines
       true
     end
 
@@ -19,6 +21,16 @@ def string # :nodoc:
 
     private
 
-    attr_accessor :size, :lines
+    attr_accessor :lines, :max_log_lines, :max_log_length
+
+    def truncate(msg)
+      return msg unless msg.size > max_log_length
+
+      suffix = +"..."
+      suffix << "\n" if msg.end_with?("\n")
+      msg = msg[0, max_log_length - suffix.size]
+
+      "#{msg}#{suffix}"
+    end
   end
 end

spec/lamian/log_device_spec.rb

@@ -1,16 +1,30 @@
 # frozen_string_literal: true
 
 describe Lamian::LogDevice do
-  subject(:logdev) { described_class.new(5) }
+  subject(:logdev) { described_class.new(max_log_lines: 5, max_log_length: 20) }
 
   it "saves log" do
-    logdev.write("Hello ")
-    logdev.write("world!")
-    expect(logdev.string).to eq("Hello world!")
+    logdev.write("Hello\n")
+    logdev.write("world!\n")
+    expect(logdev.string).to eq("Hello\nworld!\n")
   end
 
   it "only stores 5 latest log lines" do
     8.times { |x| logdev.write(x + 1) }
     expect(logdev.string).to eq("45678")
   end
+
+  context "long log lines" do
+    it "truncates log" do
+      logdev.write("Hello world, this is me!")
+      expect(logdev.string).to eq("Hello world, this...")
+    end
+
+    context "line with newline in the end" do
+      it "truncates log and adds newline" do
+        logdev.write("Hello world, this is me!\n")
+        expect(logdev.string).to eq("Hello world, thi...\n")
+      end
+    end
+  end
 end