Add ability to filter logs send to Better Stack (#23)

Author: PetrHeinz

.github/workflows/main.yml

@@ -23,7 +23,6 @@ jobs:
           - 2.5
           - 2.4
           - 2.3
-          - 2.2
           - jruby-9.4.3.0
           - jruby-9.2.14.0
           - truffleruby-23.0.0

example-project/Gemfile

@@ -1,2 +1,2 @@
 source 'https://rubygems.org'
-gem "logtail"
+gem "logtail", "~> 0.1.12"

example-project/Gemfile.lock

@@ -1,9 +1,9 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    logtail (0.1.9)
+    logtail (0.1.12)
       msgpack (~> 1.0)
-    msgpack (1.7.1)
+    msgpack (1.7.2)
 
 PLATFORMS
   ruby

example-project/main.rb

@@ -15,6 +15,9 @@
 http_device = Logtail::LogDevices::HTTP.new(ARGV[0])
 logger = Logtail::Logger.new(http_device)
 
+# Filter logs that shouldn't be sent to Better Stack, see {Logtail::LogEntry} for available attributes
+Logtail.config.filter_sent_to_better_stack { |log_entry| log_entry.message.include?("DO_NOT_SEND") }
+
 # LOGGING
 
 # Send debug logs messages using the debug() method
@@ -33,6 +36,9 @@
     }
 )
 
+# Some messages can be filtered, see {Logtail::Config#filter_sent_to_better_stack} call above
+logger.info("This message will not be sent to Better Stack because it contains 'DO_NOT_SEND'")
+
 # Send error messages using the error() method
 logger.error("Oops! An error occurred!")
 

lib/logtail/config.rb

@@ -32,6 +32,28 @@ def call(severity, timestamp, progname, msg)
 
     attr_writer :http_body_limit
 
+    # Whether a particular {Logtail::LogEntry} should be sent to Better Stack
+    def send_to_better_stack?(log_entry)
+      !@better_stack_filters&.any? { |blocker| blocker.call(log_entry) }
+    rescue => e
+      debug { "Could not determine whether to send LogEntry to Better Stack (assumed yes): #{e}" }
+      true
+    end
+
+    # This allows filtering logs that are sent to Better Stack. Can be called multiple times, all filters will
+    # be applied. If the passed block RETURNS TRUE for a particular LogEntry, it WILL NOT BE SENT to Better Stack.
+    #
+    # See {Logtail::LogEntry} for available attributes of the block parameter.
+    #
+    # @example Rails
+    #   config.logtail.filter_sent_to_better_stack { |log_entry| log_entry.context_snapshot[:http][:path].start_with?('_') }
+    # @example Everything else
+    #   Logtail.config.filter_sent_to_better_stack { |log_entry| log_entry.message.include?('IGNORE') }
+    def filter_sent_to_better_stack(&block)
+      @better_stack_filters ||= []
+      @better_stack_filters << -> (log_entry) { yield(log_entry) }
+    end
+
     # Convenience method for logging debug statements to the debug logger
     # set in this class.
     # @private

lib/logtail/log_devices/http.rb

@@ -89,6 +89,8 @@ def initialize(source_token, options = {})
       # size is constricted by the Logtail API. The actual application limit is a multiple
       # of this. Hence the `@request_queue`.
       def write(msg)
+        return unless Logtail.config.send_to_better_stack?(msg)
+
         @msg_queue.enq(msg)
 
         # Lazily start flush threads to ensure threads are alive after forking processes.

lib/logtail/version.rb

@@ -1,3 +1,3 @@
 module Logtail
-  VERSION = "0.1.11"
+  VERSION = "0.1.12"
 end

logtail.gemspec

@@ -18,7 +18,7 @@ Gem::Specification.new do |spec|
   spec.metadata["homepage_uri"] = spec.homepage
   spec.metadata["source_code_uri"] = spec.homepage
 
-  spec.required_ruby_version = Gem::Requirement.new(">= 2.2.0")
+  spec.required_ruby_version = Gem::Requirement.new(">= 2.3")
 
   spec.files         = `git ls-files`.split("\n")
   spec.test_files    = `git ls-files -- {test,spec,features}/*`.split("\n")