Class: AwsLogs::Tail
Constant Summary collapse
- @@waiting_already_shown =
false
- @@global_end_loop_signal =
For backwards compatibility. This is not thread-safe.
false
Instance Attribute Summary collapse
-
#logger ⇒ Object
readonly
Returns the value of attribute logger.
Class Method Summary collapse
Instance Method Summary collapse
- #check_follow_until! ⇒ Object
-
#codebuild_complete?(message) ⇒ Boolean
- Container
-
2024/03/27 02:35:32.086024 Phase complete: BUILD State: SUCCEEDED.
- #data(since = "24h", quiet_not_found = false) ⇒ Object
- #default_logger ⇒ Object
-
#display ⇒ Object
There can be duplicated events as events can be written to the exact same timestamp.
- #filter_log_events(start_time, end_time, next_token = nil) ⇒ Object
-
#initialize(options = {}) ⇒ Tail
constructor
A new instance of Tail.
- #output ⇒ Object
-
#refresh_events(start_time, end_time) ⇒ Object
TODO: lazy Enum or else its seems stuck for long –since.
- #reset ⇒ Object
-
#run ⇒ Object
The start and end time is useful to limit results and make the API fast.
- #say(text) ⇒ Object
- #set_trap ⇒ Object
- #show_if(e) ⇒ Object
- #show_if? ⇒ Boolean
-
#stop_follow! ⇒ Object
The stop_follow! results in a little waiting because it signals to break the polling loop.
Methods included from AwsServices
Constructor Details
#initialize(options = {}) ⇒ Tail
Returns a new instance of Tail.
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# File 'lib/aws_logs/tail.rb', line 6 def initialize( = {}) super # Setting to ensure matches default CLI option @follow = @options[:follow].nil? ? true : @options[:follow] @refresh_rate = @options[:refresh_rate] || 2 @wait_exists = @options[:wait_exists] @wait_exists_retries = @options[:wait_exists_retries] @logger = @options[:logger] || default_logger # separate logger instance for thread-safety @loop_count = 0 @output = [] # for specs reset set_trap end |
Instance Attribute Details
#logger ⇒ Object (readonly)
Returns the value of attribute logger.
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# File 'lib/aws_logs/tail.rb', line 5 def logger @logger end |
Class Method Details
.stop_follow! ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 204 def self.stop_follow! logger.info "WARN: AwsLogs::Tail.stop_follow! is deprecated. Use AwsLogs::Tail#stop_follow! instead which is thread-safe." @@global_end_loop_signal = true end |
Instance Method Details
#check_follow_until! ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 171 def check_follow_until! follow_until = @options[:follow_until] return unless follow_until = @events.map(&:message) @end_loop_signal = .detect { |m| m.include?(follow_until) } end |
#codebuild_complete?(message) ⇒ Boolean
- Container
-
2024/03/27 02:35:32.086024 Phase complete: BUILD State: SUCCEEDED
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# File 'lib/aws_logs/tail.rb', line 167 def codebuild_complete?() .starts_with?("[Container]") && .include?("Phase complete: BUILD") end |
#data(since = "24h", quiet_not_found = false) ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 34 def data(since = "24h", quiet_not_found = false) since, now = Since.new(since).to_i, current_now resp = filter_log_events(since, now) resp.events rescue Aws::CloudWatchLogs::Errors::ResourceNotFoundException => e logger.info "WARN: #{e.class}: #{e.}" unless quiet_not_found [] end |
#default_logger ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 21 def default_logger logger = ActiveSupport::Logger.new($stdout) # The ActiveSupport::Logger::SimpleFormatter always adds extra lines to the output, # unlike puts, which only adds a newline if it's needed. # We want the simpler puts behavior. logger.formatter = proc { |severity, , progname, msg| msg = "#{msg}\n" unless msg.end_with?("\n") "#{msg}" } logger.level = ENV["AWS_LOGS_LOG_LEVEL"] || :info logger end |
#display ⇒ Object
There can be duplicated events as events can be written to the exact same timestamp. So also track the last_shown_event and prevent duplicate log lines from re-appearing.
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# File 'lib/aws_logs/tail.rb', line 132 def display new_events = @events shown_index = new_events.find_index { |e| e.event_id == @last_shown_event&.event_id } if shown_index new_events = @events[shown_index + 1..-1] || [] end new_events.each do |e| time = Time.at(e. / 1000).utc.to_s.color(:green) unless @options[:format] == "plain" line = [time, e.].compact format = @options[:format] || "detailed" line.insert(1, e.log_stream_name.color(:purple)) if format == "detailed" filtered = show_if? ? show_if(e) : true say line.join(" ") if !@options[:silence] && filtered end @last_shown_event = @events.last check_follow_until! end |
#filter_log_events(start_time, end_time, next_token = nil) ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 113 def filter_log_events(start_time, end_time, next_token = nil) = { log_group_name: @log_group_name, # required start_time: start_time, end_time: end_time # limit: 1000, # interleaved: true, } [:log_stream_names] = @options[:log_stream_names] if @options[:log_stream_names] [:log_stream_name_prefix] = @options[:log_stream_name_prefix] if @options[:log_stream_name_prefix] [:filter_pattern] = @options[:filter_pattern] if @options[:filter_pattern] [:next_token] = next_token if next_token != :start && !next_token.nil? cloudwatchlogs.filter_log_events() end |
#output ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 183 def output @output.join("\n") + "\n" end |
#refresh_events(start_time, end_time) ⇒ Object
TODO: lazy Enum or else its seems stuck for long –since
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# File 'lib/aws_logs/tail.rb', line 99 def refresh_events(start_time, end_time) @events = [] next_token = :start # TODO: can hit throttle limit if there are lots of pages while next_token resp = filter_log_events(start_time, end_time, next_token) @events += resp.events next_token = resp.next_token end @events end |
#reset ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 43 def reset @events = [] # constantly replaced with recent events @last_shown_event_id = nil @completed = nil end |
#run ⇒ Object
The start and end time is useful to limit results and make the API fast. We’ll leverage it like so:
1. load all events from an initial since time
2. after that load events pass that first window
It’s a sliding window of time we’re using.
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# File 'lib/aws_logs/tail.rb', line 56 def run # We overlap the sliding window because CloudWatch logs can receive or send the logs out of order. # For example, a bunch of logs can all come in at the same second, but they haven't registered to CloudWatch logs # yet. If we don't overlap the sliding window then we'll miss the logs that were delayed in registering. overlap = 60 * 1000 # overlap the sliding window by a minute since, now = initial_since, current_now @wait_retries ||= 0 until end_loop? refresh_events(since, now) display # @last_shown_event.timestamp changes and creates a "sliding window" # The overlap is a just in case buffer since = @last_shown_event ? @last_shown_event. - overlap : initial_since now = current_now loop_count! sleep @refresh_rate if @follow && !ENV["AWS_LOGS_TEST"] end # Refresh and display a final time in case the end_loop gets interrupted by stop_follow! refresh_events(since, now) display rescue Aws::CloudWatchLogs::Errors::ResourceNotFoundException => e if @wait_exists seconds = Integer(@options[:wait_exists_seconds] || 5) unless @@waiting_already_shown logger.info "Waiting for log group to exist: #{@log_group_name}" @@waiting_already_shown = true end sleep seconds @wait_retries += 1 logger.info "Waiting #{seconds} seconds. #{@wait_retries} of #{@wait_exists_retries} retries" if !@wait_exists_retries || @wait_retries < @wait_exists_retries retry end logger.info "Giving up waiting for log group to exist" end logger.info "ERROR: #{e.class}: #{e.}".color(:red) logger.info "Log group #{@log_group_name} not found." end |
#say(text) ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 179 def say(text) ENV["AWS_LOGS_TEST"] ? @output << text : logger.info(text) end |
#set_trap ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 187 def set_trap Signal.trap("INT") { # puts must be used here instead of logger.info or else get Thread-safe error puts "\nCtrl-C detected. Exiting..." exit # immediate exit } end |
#show_if(e) ⇒ Object
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# File 'lib/aws_logs/tail.rb', line 156 def show_if(e) filter = @options[:show_if] case filter when ->(f) { f.respond_to?(:call) } filter.call(e) else filter # true or false end end |
#show_if? ⇒ Boolean
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# File 'lib/aws_logs/tail.rb', line 152 def show_if? !@options[:show_if].nil? end |
#stop_follow! ⇒ Object
The stop_follow! results in a little waiting because it signals to break the polling loop. Since it’s in the middle of the loop process, the loop will finish the sleep 5 first. So it can pause from 0-5 seconds.
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# File 'lib/aws_logs/tail.rb', line 198 def stop_follow! @end_loop_signal = true end |