require 'socket'
require 'net/https'
require 'net/http'
require 'logger'
require 'zlib'
require 'stringio'
require 'new_relic/data_serialization'
module NewRelic
module Agent
# The Agent is a singleton that is instantiated when the plugin is
# activated. It collects performance data from ruby applications
# in realtime as the application runs, and periodically sends that
# data to the NewRelic server.
class Agent
# Specifies the version of the agent's communication protocol with
# the NewRelic hosted site.
PROTOCOL_VERSION = 8
# 14105: v8 (tag 2.10.3)
# (no v7)
# 10379: v6 (not tagged)
# 4078: v5 (tag 2.5.4)
# 2292: v4 (tag 2.3.6)
# 1754: v3 (tag 2.3.0)
# 534: v2 (shows up in 2.1.0, our first tag)
def initialize
@launch_time = Time.now
@metric_ids = {}
@stats_engine = NewRelic::Agent::StatsEngine.new
@transaction_sampler = NewRelic::Agent::TransactionSampler.new
@sql_sampler = NewRelic::Agent::SqlSampler.new
@stats_engine.transaction_sampler = @transaction_sampler
@error_collector = NewRelic::Agent::ErrorCollector.new
@connect_attempts = 0
@request_timeout = NewRelic::Control.instance.fetch('timeout', 2 * 60)
@last_harvest_time = Time.now
@obfuscator = lambda {|sql| NewRelic::Agent::Database.default_sql_obfuscator(sql) }
end
# contains all the class-level methods for NewRelic::Agent::Agent
module ClassMethods
# Should only be called by NewRelic::Control - returns a
# memoized singleton instance of the agent, creating one if needed
def instance
@instance ||= self.new
end
end
# Holds all the methods defined on NewRelic::Agent::Agent
# instances
module InstanceMethods
# holds a proc that is used to obfuscate sql statements
attr_reader :obfuscator
# the statistics engine that holds all the timeslice data
attr_reader :stats_engine
# the transaction sampler that handles recording transactions
attr_reader :transaction_sampler
attr_reader :sql_sampler
# error collector is a simple collection of recorded errors
attr_reader :error_collector
# whether we should record raw, obfuscated, or no sql
attr_reader :record_sql
# a cached set of metric_ids to save the collector some time -
# it returns a metric id for every metric name we send it, and
# in the future we transmit using the metric id only
attr_reader :metric_ids
# in theory a set of rules applied by the agent to the output
# of its metrics. Currently unimplemented
attr_reader :url_rules
# a configuration for the Real User Monitoring system -
# handles things like static setup of the header for inclusion
# into pages
attr_reader :beacon_configuration
# Returns the length of the unsent errors array, if it exists,
# otherwise nil
def unsent_errors_size
@unsent_errors.length if @unsent_errors
end
# Returns the length of the traces array, if it exists,
# otherwise nil
def unsent_traces_size
@traces.length if @traces
end
# Initializes the unsent timeslice data hash, if needed, and
# returns the number of keys it contains
def unsent_timeslice_data
@unsent_timeslice_data ||= {}
@unsent_timeslice_data.keys.length
end
# fakes out a transaction that did not happen in this process
# by creating apdex, summary metrics, and recording statistics
# for the transaction
#
# This method is *deprecated* - it may be removed in future
# versions of the agent
def record_transaction(duration_seconds, options={})
is_error = options['is_error'] || options['error_message'] || options['exception']
metric = options['metric']
metric ||= options['uri'] # normalize this with url rules
raise "metric or uri arguments required" unless metric
metric_info = NewRelic::MetricParser::MetricParser.for_metric_named(metric)
if metric_info.is_web_transaction?
NewRelic::Agent::Instrumentation::MetricFrame.record_apdex(metric_info, duration_seconds, duration_seconds, is_error)
end
metrics = metric_info.summary_metrics
metrics << metric
metrics.each do |name|
stats = stats_engine.get_stats_no_scope(name)
stats.record_data_point(duration_seconds)
end
if is_error
if options['exception']
e = options['exception']
elsif options['error_message']
e = StandardError.new options['error_message']
else
e = StandardError.new 'Unknown Error'
end
error_collector.notice_error e, :uri => options['uri'], :metric => metric
end
# busy time ?
end
# This method should be called in a forked process after a fork.
# It assumes the parent process initialized the agent, but does
# not assume the agent started.
#
# The call is idempotent, but not re-entrant.
#
# * It clears any metrics carried over from the parent process
# * Restarts the sampler thread if necessary
# * Initiates a new agent run and worker loop unless that was done
# in the parent process and +:force_reconnect+ is not true
#
# Options:
# * :force_reconnect => true to force the spawned process to
# establish a new connection, such as when forking a long running process.
# The default is false--it will only connect to the server if the parent
# had not connected.
# * :keep_retrying => false if we try to initiate a new
# connection, this tells me to only try it once so this method returns
# quickly if there is some kind of latency with the server.
def after_fork(options={})
# @connected gets false after we fail to connect or have an error
# connecting. @connected has nil if we haven't finished trying to connect.
# or we didn't attempt a connection because this is the master process
# log.debug "Agent received after_fork notice in #$$: [#{control.agent_enabled?}; monitor=#{control.monitor_mode?}; connected: #{@connected.inspect}; thread=#{@worker_thread.inspect}]"
return if !control.agent_enabled? or
!control.monitor_mode? or
@connected == false or
@worker_thread && @worker_thread.alive?
log.info "Starting the worker thread in #$$ after forking."
# Clear out stats that are left over from parent process
reset_stats
# Don't ever check to see if this is a spawner. If we're in a forked process
# I'm pretty sure we're not also forking new instances.
start_worker_thread(options)
@stats_engine.start_sampler_thread
end
# True if we have initialized and completed 'start'
def started?
@started
end
# Return nil if not yet connected, true if successfully started
# and false if we failed to start.
def connected?
@connected
end
# Attempt a graceful shutdown of the agent, running the worker
# loop if it exists and is running.
#
# Options:
# :force_send => (true/false) # force the agent to send data
# before shutting down
def shutdown(options={})
run_loop_before_exit = options.fetch(:force_send, false)
return if not started?
if @worker_loop
@worker_loop.run_task if run_loop_before_exit
@worker_loop.stop
log.debug "Starting Agent shutdown"
# if litespeed, then ignore all future SIGUSR1 - it's
# litespeed trying to shut us down
if control.dispatcher == :litespeed
Signal.trap("SIGUSR1", "IGNORE")
Signal.trap("SIGTERM", "IGNORE")
end
begin
NewRelic::Agent.disable_all_tracing do
graceful_disconnect
end
rescue => e
log.error e
log.error e.backtrace.join("\n")
end
end
@started = nil
end
# Tells the statistics engine we are starting a new transaction
def start_transaction
@stats_engine.start_transaction
end
# Tells the statistics engine we are ending a transaction
def end_transaction
@stats_engine.end_transaction
end
# Sets a thread local variable as to whether we should or
# should not record sql in the current thread. Returns the
# previous value, if there is one
def set_record_sql(should_record)
prev = Thread::current[:record_sql]
Thread::current[:record_sql] = should_record
prev.nil? || prev
end
# Sets a thread local variable as to whether we should or
# should not record transaction traces in the current
# thread. Returns the previous value, if there is one
def set_record_tt(should_record)
prev = Thread::current[:record_tt]
Thread::current[:record_tt] = should_record
prev.nil? || prev
end
# Push flag indicating whether we should be tracing in this
# thread. This uses a stack which allows us to disable tracing
# children of a transaction without affecting the tracing of
# the whole transaction
def push_trace_execution_flag(should_trace=false)
value = Thread.current[:newrelic_untraced]
if (value.nil?)
Thread.current[:newrelic_untraced] = []
end
Thread.current[:newrelic_untraced] << should_trace
end
# Pop the current trace execution status. Restore trace execution status
# to what it was before we pushed the current flag.
def pop_trace_execution_flag
Thread.current[:newrelic_untraced].pop if Thread.current[:newrelic_untraced]
end
# Shorthand to the NewRelic::Agent.logger method
def log
NewRelic::Agent.logger
end
# Herein lies the corpse of the former 'start' method. May
# it's unmatched flog score rest in pieces.
module Start
# Check whether we have already started, which is an error condition
def already_started?
if started?
control.log!("Agent Started Already!", :error)
true
end
end
# The agent is disabled when it is not force enabled by the
# 'agent_enabled' option (e.g. in a manual start), or
# enabled normally through the configuration file
def disabled?
!control.agent_enabled?
end
# Logs the dispatcher to the log file to assist with
# debugging. When no debugger is present, logs this fact to
# assist with proper dispatcher detection
def log_dispatcher
dispatcher_name = control.dispatcher.to_s
return if log_if(dispatcher_name.empty?, :info, "No dispatcher detected.")
log.info "Dispatcher: #{dispatcher_name}"
end
# Logs the configured application names
def log_app_names
log.info "Application: #{control.app_names.join(", ")}"
end
# Connecting in the foreground blocks further startup of the
# agent until we have a connection - useful in cases where
# you're trying to log a very-short-running process and want
# to get statistics from before a server connection
# (typically 20 seconds) exists
def connect_in_foreground
NewRelic::Agent.disable_all_tracing { connect(:keep_retrying => false) }
end
# If we're using sinatra, old versions run in an at_exit
# block so we should probably know that
def using_sinatra?
defined?(Sinatra::Application)
end
# we should not set an at_exit block if people are using
# these as they don't do standard at_exit behavior per MRI/YARV
def weird_ruby?
NewRelic::LanguageSupport.using_engine?('rbx') ||
NewRelic::LanguageSupport.using_engine?('jruby') ||
using_sinatra?
end
# Installs our exit handler, which exploits the weird
# behavior of at_exit blocks to make sure it runs last, by
# doing an at_exit within an at_exit block.
def install_exit_handler
if control.send_data_on_exit && !weird_ruby?
# Our shutdown handler needs to run after other shutdown handlers
at_exit { at_exit { shutdown } }
end
end
# Tells us in the log file where the log file is
# located. This seems redundant, but can come in handy when
# we have some log file path set by the user which parses
# incorrectly, sending the log file to who-knows-where
def notify_log_file_location
log_file = NewRelic::Control.instance.log_file
log_if(File.exists?(log_file.to_s), :info,
"Agent Log at #{log_file}")
end
# Classy logging of the agent version and the current pid,
# so we can disambiguate processes in the log file and make
# sure they're running a reasonable version
def log_version_and_pid
log.info "New Relic Ruby Agent #{NewRelic::VERSION::STRING} Initialized: pid = #{$$}"
end
# A helper method that logs a condition if that condition is
# true. Mentally cleaner than having every method set a
# local and log if it is true
def log_if(boolean, level, message)
self.log.send(level, message) if boolean
boolean
end
# A helper method that logs a condition unless that
# condition is true. Mentally cleaner than having every
# method set a local and log unless it is true
def log_unless(boolean, level, message)
self.log.send(level, message) unless boolean
boolean
end
# Warn the user if they have configured their agent not to
# send data, that way we can see this clearly in the log file
def monitoring?
log_unless(control.monitor_mode?, :warn, "Agent configured not to send data in this environment - edit newrelic.yml to change this")
end
# Tell the user when the license key is missing so they can
# fix it by adding it to the file
def has_license_key?
log_unless(control.license_key, :error, "No license key found. Please edit your newrelic.yml file and insert your license key.")
end
# A correct license key exists and is of the proper length
def has_correct_license_key?
has_license_key? && correct_license_length
end
# A license key is an arbitrary 40 character string,
# usually looks something like a SHA1 hash
def correct_license_length
key = control.license_key
log_unless((key.length == 40), :error, "Invalid license key: #{key}")
end
# If we're using a dispatcher that forks before serving
# requests, we need to wait until the children are forked
# before connecting, otherwise the parent process sends odd data
def using_forking_dispatcher?
log_if([:passenger, :unicorn].include?(control.dispatcher), :info, "Connecting workers after forking.")
end
# Sanity-check the agent configuration and start the agent,
# setting up the worker thread and the exit handler to shut
# down the agent
def check_config_and_start_agent
return unless monitoring? && has_correct_license_key?
return if using_forking_dispatcher?
connect_in_foreground if control.sync_startup
start_worker_thread
install_exit_handler
end
end
include Start
# Logs a bunch of data and starts the agent, if needed
def start
return if already_started? || disabled?
@started = true
@local_host = determine_host
log_dispatcher
log_app_names
config_transaction_tracer
check_config_and_start_agent
log_version_and_pid
notify_log_file_location
end
# Clear out the metric data, errors, and transaction traces,
# making sure the agent is in a fresh state
def reset_stats
@stats_engine.reset_stats
@unsent_errors = []
@traces = nil
@unsent_timeslice_data = {}
@last_harvest_time = Time.now
@launch_time = Time.now
end
private
def collector
@collector ||= control.server
end
# All of this module used to be contained in the
# start_worker_thread method - this is an artifact of
# refactoring and can be moved, renamed, etc at will
module StartWorkerThread
# disable transaction sampling if disabled by the server
# and we're not in dev mode
def check_transaction_sampler_status
if control.developer_mode? || @should_send_samples
@transaction_sampler.enable
else
@transaction_sampler.disable
end
end
def check_sql_sampler_status
# disable sql sampling if disabled by the server
# and we're not in dev mode
if @sql_sampler.config.fetch('enabled', true) && ['raw', 'obfuscated'].include?(@sql_sampler.config.fetch('record_sql', 'obfuscated').to_s) && @transaction_sampler.config.fetch('enabled', true)
@sql_sampler.enable
else
@sql_sampler.disable
end
end
# logs info about the worker loop so users can see when the
# agent actually begins running in the background
def log_worker_loop_start
log.info "Reporting performance data every #{@report_period} seconds."
log.debug "Running worker loop"
end
# Creates the worker loop and loads it with the instructions
# it should run every @report_period seconds
def create_and_run_worker_loop
@worker_loop = WorkerLoop.new
@worker_loop.run(@report_period) do
save_or_transmit_data
end
end
# Handles the case where the server tells us to restart -
# this clears the data, clears connection attempts, and
# waits a while to reconnect.
def handle_force_restart(error)
log.info error.message
reset_stats
@metric_ids = {}
@connected = nil
sleep 30
end
# when a disconnect is requested, stop the current thread, which
# is the worker thread that gathers data and talks to the
# server.
def handle_force_disconnect(error)
log.error "New Relic forced this agent to disconnect (#{error.message})"
disconnect
end
# there is a problem with connecting to the server, so we
# stop trying to connect and shut down the agent
def handle_server_connection_problem(error)
log.error "Unable to establish connection with the server. Run with log level set to debug for more information."
log.debug("#{error.class.name}: #{error.message}\n#{error.backtrace.first}")
disconnect
end
# Handles an unknown error in the worker thread by logging
# it and disconnecting the agent, since we are now in an
# unknown state
def handle_other_error(error)
log.error "Terminating worker loop: #{error.class.name}: #{error.message}\n #{error.backtrace.join("\n ")}"
disconnect
end
# a wrapper method to handle all the errors that can happen
# in the connection and worker thread system. This
# guarantees a no-throw from the background thread.
def catch_errors
yield
rescue NewRelic::Agent::ForceRestartException => e
handle_force_restart(e)
retry
rescue NewRelic::Agent::ForceDisconnectException => e
handle_force_disconnect(e)
rescue NewRelic::Agent::ServerConnectionException => e
handle_server_connection_problem(e)
rescue => e
handle_other_error(e)
end
# This is the method that is run in a new thread in order to
# background the harvesting and sending of data during the
# normal operation of the agent.
#
# Takes connection options that determine how we should
# connect to the server, and loops endlessly - typically we
# never return from this method unless we're shutting down
# the agent
def deferred_work!(connection_options)
catch_errors do
NewRelic::Agent.disable_all_tracing do
# We try to connect. If this returns false that means
# the server rejected us for a licensing reason and we should
# just exit the thread. If it returns nil
# that means it didn't try to connect because we're in the master.
connect(connection_options)
if @connected
check_transaction_sampler_status
check_sql_sampler_status
log_worker_loop_start
create_and_run_worker_loop
# never reaches here unless there is a problem or
# the agent is exiting
else
log.debug "No connection. Worker thread ending."
end
end
end
end
end
include StartWorkerThread
# Try to launch the worker thread and connect to the server.
#
# See #connect for a description of connection_options.
def start_worker_thread(connection_options = {})
log.debug "Creating Ruby Agent worker thread."
@worker_thread = Thread.new do
deferred_work!(connection_options)
end # thread new
@worker_thread['newrelic_label'] = 'Worker Loop'
end
# A shorthand for NewRelic::Control.instance
def control
NewRelic::Control.instance
end
# This module is an artifact of a refactoring of the connect
# method - all of its methods are used in that context, so it
# can be refactored at will. It should be fully tested
module Connect
# the frequency with which we should try to connect to the
# server at the moment.
attr_accessor :connect_retry_period
# number of attempts we've made to contact the server
attr_accessor :connect_attempts
# Disconnect just sets connected to false, which prevents
# the agent from trying to connect again
def disconnect
@connected = false
true
end
# We've tried to connect if @connected is not nil, or if we
# are forcing reconnection (i.e. in the case of an
# after_fork with long running processes)
def tried_to_connect?(options)
!(@connected.nil? || options[:force_reconnect])
end
# We keep trying by default, but you can disable it with the
# :keep_retrying option set to false
def should_keep_retrying?(options)
@keep_retrying = (options[:keep_retrying].nil? || options[:keep_retrying])
end
# Retry period is a minute for each failed attempt that
# we've made. This should probably do some sort of sane TCP
# backoff to prevent hammering the server, but a minute for
# each attempt seems to work reasonably well.
def get_retry_period
return 600 if self.connect_attempts > 6
connect_attempts * 60
end
def increment_retry_period! #:nodoc:
self.connect_retry_period=(get_retry_period)
end
# We should only retry when there has not been a more
# serious condition that would prevent it. We increment the
# connect attempts and the retry period, to prevent constant
# connection attempts, and tell the user what we're doing by
# logging.
def should_retry?
if @keep_retrying
self.connect_attempts=(connect_attempts + 1)
increment_retry_period!
log.info "Will re-attempt in #{connect_retry_period} seconds"
true
else
disconnect
false
end
end
# When we have a problem connecting to the server, we need
# to tell the user what happened, since this is not an error
# we can handle gracefully.
def log_error(error)
log.error "Error establishing connection with New Relic Service at #{control.server}: #{error.message}"
log.debug error.backtrace.join("\n")
end
# When the server sends us an error with the license key, we
# want to tell the user that something went wrong, and let
# them know where to go to get a valid license key
#
# After this runs, it disconnects the agent so that it will
# no longer try to connect to the server, saving the
# application and the server load
def handle_license_error(error)
log.error error.message
log.info "Visit NewRelic.com to obtain a valid license key, or to upgrade your account."
disconnect
end
# If we are using a seed and token to validate the agent, we
# should debug log that fact so that debug logs include a
# clue that token authentication is what will be used
def log_seed_token
if control.validate_seed
log.debug "Connecting with validation seed/token: #{control.validate_seed}/#{control.validate_token}"
end
end
# Checks whether we should send environment info, and if so,
# returns the snapshot from the local environment
def environment_for_connect
control['send_environment_info'] != false ? control.local_env.snapshot : []
end
# These validation settings are used for cases where a
# dynamic server is spun up for clients - partners can
# include a seed and token to indicate that the host is
# allowed to connect, rather than setting a unique hostname
def validate_settings
{
:seed => control.validate_seed,
:token => control.validate_token
}
end
# Initializes the hash of settings that we send to the
# server. Returns a literal hash containing the options
def connect_settings
{
:pid => $$,
:host => @local_host,
:app_name => control.app_names,
:language => 'ruby',
:agent_version => NewRelic::VERSION::STRING,
:environment => environment_for_connect,
:settings => control.settings,
:validate => validate_settings
}
end
# Does some simple logging to make sure that our seed and
# token for verification are correct, then returns the
# connect data passed back from the server
def connect_to_server
log_seed_token
connect_data = invoke_remote(:connect, connect_settings)
end
# Configures the error collector if the server says that we
# are allowed to send errors. Pretty simple, and logs at
# debug whether errors will or will not be sent.
def configure_error_collector!(server_enabled)
# Reinitialize the error collector
@error_collector = NewRelic::Agent::ErrorCollector.new
# Ask for permission to collect error data
enabled = if error_collector.config_enabled && server_enabled
error_collector.enabled = true
else
error_collector.enabled = false
end
log.debug "Errors will #{enabled ? '' : 'not '}be sent to the New Relic service."
end
# Random sampling is enabled based on a sample rate, which
# is the n in "every 1/n transactions is added regardless of
# its length".
#
# uses a sane default for sampling rate if the sampling rate
# is zero, since the collector currently sends '0' as a
# sampling rate for all accounts, which is probably for
# legacy reasons
def enable_random_samples!(sample_rate)
sample_rate = 10 unless sample_rate.to_i > 0
@transaction_sampler.random_sampling = true
@transaction_sampler.sampling_rate = sample_rate
log.info "Transaction sampling enabled, rate = #{@transaction_sampler.sampling_rate}"
end
# this entire method should be done on the transaction
# sampler object, rather than here. We should pass in the
# sampler config.
def config_transaction_tracer
# Reconfigure the transaction tracer
@transaction_sampler.configure!
@sql_sampler.configure!
@should_send_samples = @config_should_send_samples = @transaction_sampler.config.fetch('enabled', true)
@should_send_random_samples = @transaction_sampler.config.fetch('random_sample', false)
set_sql_recording!
# default to 2.0, string 'apdex_f' will turn into your
# apdex * 4
@slowest_transaction_threshold = @transaction_sampler.config.fetch('transaction_threshold', 2.0).to_f
@slowest_transaction_threshold = apdex_f if apdex_f_threshold?
end
# Enables or disables the transaction tracer and sets its
# options based on the options provided to the
# method.
def configure_transaction_tracer!(server_enabled, sample_rate)
# Ask the server for permission to send transaction samples.
# determined by subscription license.
@transaction_sampler.config['enabled'] = server_enabled
@sql_sampler.configure!
@should_send_samples = @config_should_send_samples && server_enabled
if @should_send_samples
# I don't think this is ever true, but...
enable_random_samples!(sample_rate) if @should_send_random_samples
@transaction_sampler.slow_capture_threshold = @slowest_transaction_threshold
log.debug "Transaction tracing threshold is #{@slowest_transaction_threshold} seconds."
else
log.debug "Transaction traces will not be sent to the New Relic service."
end
end
# apdex_f is always 4 times the apdex_t
def apdex_f
(4 * NewRelic::Control.instance.apdex_t).to_f
end
# If the transaction threshold is set to the string
# 'apdex_f', we use 4 times the apdex_t value to record
# transactions. This gears well with using apdex since you
# will attempt to send any transactions that register as 'failing'
def apdex_f_threshold?
@transaction_sampler.config.fetch('transaction_threshold', '') =~ /apdex_f/i
end
# Sets the sql recording configuration by trying to detect
# any attempt to disable the sql collection - 'off',
# 'false', 'none', and friends. Otherwise, we accept 'raw',
# and unrecognized values default to 'obfuscated'
def set_sql_recording!
record_sql_config = @transaction_sampler.config.fetch('record_sql', :obfuscated)
case record_sql_config.to_s
when 'off'
@record_sql = :off
when 'none'
@record_sql = :off
when 'false'
@record_sql = :off
when 'raw'
@record_sql = :raw
else
@record_sql = :obfuscated
end
log_sql_transmission_warning?
end
# Warn the user when we are sending raw sql across the wire
# - they should probably be using ssl when this is true
def log_sql_transmission_warning?
log.warn("Agent is configured to send raw SQL to the service") if @record_sql == :raw
end
# Asks the collector to tell us which sub-collector we
# should be reporting to, and then does the name resolution
# on that host so we don't block on DNS during the normal
# course of agent processing
def set_collector_host!
host = invoke_remote(:get_redirect_host)
if host
@collector = control.server_from_host(host)
end
end
# Sets the collector host and connects to the server, then
# invokes the final configuration with the returned data
def query_server_for_configuration
set_collector_host!
finish_setup(connect_to_server)
end
# Takes a hash of configuration data returned from the
# server and uses it to set local variables and to
# initialize various parts of the agent that are configured
# separately.
#
# Can accommodate most arbitrary data - anything extra is
# ignored unless we say to do something with it here.
def finish_setup(config_data)
@agent_id = config_data['agent_run_id']
@report_period = config_data['data_report_period']
@url_rules = config_data['url_rules']
@beacon_configuration = BeaconConfiguration.new(config_data)
@server_side_config_enabled = config_data['listen_to_server_config']
if @server_side_config_enabled
log.info "Using config from server"
log.debug "Server provided config: #{config_data.inspect}"
end
control.merge_server_side_config(config_data) if @server_side_config_enabled
config_transaction_tracer
log_connection!(config_data)
configure_transaction_tracer!(config_data['collect_traces'], config_data['sample_rate'])
configure_error_collector!(config_data['collect_errors'])
end
# Logs when we connect to the server, for debugging purposes
# - makes sure we know if an agent has not connected
def log_connection!(config_data)
control.log! "Connected to NewRelic Service at #{@collector}"
log.debug "Agent Run = #{@agent_id}."
log.debug "Connection data = #{config_data.inspect}"
end
end
include Connect
# Serialize all the important data that the agent might want
# to send to the server. We could be sending this to file (
# common in short-running background transactions ) or
# alternately we could serialize via a pipe or socket to a
# local aggregation device
def serialize
accumulator = []
accumulator[1] = harvest_transaction_traces if @transaction_sampler
accumulator[2] = harvest_errors if @error_collector
accumulator[0] = harvest_timeslice_data
reset_stats
@metric_ids = {}
accumulator
end
public :serialize
# Accepts data as provided by the serialize method and merges
# it into our current collection of data to send. Can be
# dangerous if we re-merge the same data more than once - it
# will be sent multiple times.
def merge_data_from(data)
metrics, transaction_traces, errors = data
@stats_engine.merge_data(metrics) if metrics
if transaction_traces
if @traces
@traces = @traces + transaction_traces
else
@traces = transaction_traces
end
end
if errors
if @unsent_errors
@unsent_errors = @unsent_errors + errors
else
@unsent_errors = errors
end
end
end
public :merge_data_from
# Connect to the server and validate the license. If successful,
# @connected has true when finished. If not successful, you can
# keep calling this. Return false if we could not establish a
# connection with the server and we should not retry, such as if
# there's a bad license key.
#
# Set keep_retrying=false to disable retrying and return asap, such as when
# invoked in the foreground. Otherwise this runs until a successful
# connection is made, or the server rejects us.
#
# * :keep_retrying => false to only try to connect once, and
# return with the connection set to nil. This ensures we may try again
# later (default true).
# * force_reconnect => true if you want to establish a new connection
# to the server before running the worker loop. This means you get a separate
# agent run and New Relic sees it as a separate instance (default is false).
def connect(options)
# Don't proceed if we already connected (@connected=true) or if we tried
# to connect and were rejected with prejudice because of a license issue
# (@connected=false), unless we're forced to by force_reconnect.
return if tried_to_connect?(options)
# wait a few seconds for the web server to boot, necessary in development
@connect_retry_period = should_keep_retrying?(options) ? 10 : 0
sleep connect_retry_period
log.debug "Connecting Process to New Relic: #$0"
query_server_for_configuration
@connected_pid = $$
@connected = true
rescue NewRelic::Agent::LicenseException => e
handle_license_error(e)
rescue Timeout::Error, StandardError => e
log_error(e)
if should_retry?
retry
else
disconnect
end
end
# Who am I? Well, this method can tell you your hostname.
def determine_host
Socket.gethostname
end
# Delegates to the control class to determine the root
# directory of this project
def determine_home_directory
control.root
end
# Checks whether this process is a Passenger or Unicorn
# spawning server - if so, we probably don't intend to report
# statistics from this process
def is_application_spawner?
$0 =~ /ApplicationSpawner|^unicorn\S* master/
end
# calls the busy harvester and collects timeslice data to
# send later
def harvest_timeslice_data(time=Time.now)
# this creates timeslices that are harvested below
NewRelic::Agent::BusyCalculator.harvest_busy
@unsent_timeslice_data ||= {}
@unsent_timeslice_data = @stats_engine.harvest_timeslice_data(@unsent_timeslice_data, @metric_ids)
@unsent_timeslice_data
end
# takes an array of arrays of spec and id, adds it into the
# metric cache so we can save the collector some work by
# sending integers instead of strings
def fill_metric_id_cache(pairs_of_specs_and_ids)
Array(pairs_of_specs_and_ids).each do |metric_spec, metric_id|
@metric_ids[metric_spec] = metric_id
end
end
# note - exceptions are logged in invoke_remote. If an exception is encountered here,
# then the metric data is downsampled for another
# transmission later
def harvest_and_send_timeslice_data
now = Time.now
NewRelic::Agent.instance.stats_engine.get_stats_no_scope('Supportability/invoke_remote').record_data_point(0.0)
NewRelic::Agent.instance.stats_engine.get_stats_no_scope('Supportability/invoke_remote/metric_data').record_data_point(0.0)
harvest_timeslice_data(now)
begin
# In this version of the protocol, we get back an assoc array of spec to id.
metric_specs_and_ids = invoke_remote(:metric_data, @agent_id,
@last_harvest_time.to_f,
now.to_f,
@unsent_timeslice_data.values)
rescue Timeout::Error
# assume that the data was received. chances are that it
# was. Also, lol.
metric_specs_and_ids = []
end
fill_metric_id_cache(metric_specs_and_ids)
log.debug "#{now}: sent #{@unsent_timeslice_data.length} timeslices (#{@agent_id}) in #{Time.now - now} seconds"
# if we successfully invoked this web service, then clear the unsent message cache.
@unsent_timeslice_data = {}
@last_harvest_time = now
end
# Fills the traces array with the harvested transactions from
# the transaction sampler, subject to the setting for slowest
# transaction threshold
def harvest_transaction_traces
@traces = @transaction_sampler.harvest(@traces, @slowest_transaction_threshold)
@traces
end
def harvest_and_send_slowest_sql
# FIXME add the code to try to resend if our connection is down
sql_traces = @sql_sampler.harvest
unless sql_traces.empty?
log.debug "Sending (#{sql_traces.size}) sql traces"
begin
response = invoke_remote :sql_trace_data, sql_traces
# log.debug "Sql trace response: #{response}"
rescue
@sql_sampler.merge sql_traces
end
end
end
# This handles getting the transaction traces and then sending
# them across the wire. This includes gathering SQL
# explanations, stripping out stack traces, and normalizing
# SQL. note that we explain only the sql statements whose
# segments' execution times exceed our threshold (to avoid
# unnecessary overhead of running explains on fast queries.)
def harvest_and_send_slowest_sample
harvest_transaction_traces
unless @traces.empty?
now = Time.now
log.debug "Sending (#{@traces.length}) transaction traces"
begin
options = { :keep_backtraces => true }
options[:record_sql] = @record_sql unless @record_sql == :off
if @transaction_sampler.explain_enabled
options[:explain_sql] = @transaction_sampler.explain_threshold
end
traces = @traces.collect {|trace| trace.prepare_to_send(options)}
invoke_remote :transaction_sample_data, @agent_id, traces
rescue PostTooBigException
# we tried to send too much data, drop the first trace and
# try again
retry if @traces.shift
end
log.debug "Sent slowest sample (#{@agent_id}) in #{Time.now - now} seconds"
end
# if we succeed sending this sample, then we don't need to keep
# the slowest sample around - it has been sent already and we
# can clear the collection and move on
@traces = nil
end
# Gets the collection of unsent errors from the error
# collector. We pass back in an existing array of errors that
# may be left over from a previous send
def harvest_errors
@unsent_errors = @error_collector.harvest_errors(@unsent_errors)
@unsent_errors
end
# Handles getting the errors from the error collector and
# sending them to the server, and any error cases like trying
# to send very large errors - we drop the oldest error on the
# floor and try again
def harvest_and_send_errors
harvest_errors
if @unsent_errors && @unsent_errors.length > 0
log.debug "Sending #{@unsent_errors.length} errors"
begin
invoke_remote :error_data, @agent_id, @unsent_errors
rescue PostTooBigException
@unsent_errors.shift
retry
end
# if the remote invocation fails, then we never clear
# @unsent_errors, and therefore we can re-attempt to send on
# the next heartbeat. Note the error collector maxes out at
# 20 instances to prevent leakage
@unsent_errors = []
end
end
# This method handles the compression of the request body that
# we are going to send to the server
#
# We currently optimize for CPU here since we get roughly a 10x
# reduction in message size with this, and CPU overhead is at a
# premium. For extra-large posts, we use the higher compression
# since otherwise it actually errors out.
#
# We do not compress if content is smaller than 64kb. There are
# problems with bugs in Ruby in some versions that expose us
# to a risk of segfaults if we compress aggressively.
#
# medium payloads get fast compression, to save CPU
# big payloads get all the compression possible, to stay under
# the 2,000,000 byte post threshold
def compress_data(object)
dump = Marshal.dump(object)
dump_size = dump.size
return [dump, 'identity'] if dump_size < (64*1024)
compressed_dump = Zlib::Deflate.deflate(dump, Zlib::DEFAULT_COMPRESSION)
# this checks to make sure mongrel won't choke on big uploads
check_post_size(compressed_dump)
[compressed_dump, 'deflate']
end
# Raises a PostTooBigException if the post_string is longer
# than the limit configured in the control object
def check_post_size(post_string)
# TODO: define this as a config option on the server side
return if post_string.size < control.post_size_limit
log.warn "Tried to send too much data: #{post_string.size} bytes"
raise PostTooBigException
end
# Posts to the specified server
#
# Options:
# - :uri => the path to request on the server (a misnomer of
# course)
# - :encoding => the encoding to pass to the server
# - :collector => a URI object that responds to the 'name' method
# and returns the name of the collector to
# contact
# - :data => the data to send as the body of the request
def send_request(opts)
request = Net::HTTP::Post.new(opts[:uri], 'CONTENT-ENCODING' => opts[:encoding], 'HOST' => opts[:collector].name)
request['user-agent'] = user_agent
request.content_type = "application/octet-stream"
request.body = opts[:data]
log.debug "Connect to #{opts[:collector]}#{opts[:uri]}"
response = nil
http = control.http_connection(collector)
http.read_timeout = nil
begin
NewRelic::TimerLib.timeout(@request_timeout) do
response = http.request(request)
end
rescue Timeout::Error
log.warn "Timed out trying to post data to New Relic (timeout = #{@request_timeout} seconds)" unless @request_timeout < 30
raise
end
if response.is_a? Net::HTTPServiceUnavailable
raise NewRelic::Agent::ServerConnectionException, "Service unavailable (#{response.code}): #{response.message}"
elsif response.is_a? Net::HTTPGatewayTimeOut
log.debug("Timed out getting response: #{response.message}")
raise Timeout::Error, response.message
elsif response.is_a? Net::HTTPRequestEntityTooLarge
raise PostTooBigException
elsif !(response.is_a? Net::HTTPSuccess)
raise NewRelic::Agent::ServerConnectionException, "Unexpected response from server (#{response.code}): #{response.message}"
end
response
end
# Decompresses the response from the server, if it is gzip
# encoded, otherwise returns it verbatim
def decompress_response(response)
if response['content-encoding'] != 'gzip'
log.debug "Uncompressed content returned"
return response.body
end
log.debug "Decompressing return value"
i = Zlib::GzipReader.new(StringIO.new(response.body))
i.read
end
# unmarshals the response and raises it if it is an exception,
# so we can handle it in nonlocally
def check_for_exception(response)
dump = decompress_response(response)
value = Marshal.load(dump)
raise value if value.is_a? Exception
value
end
# The path on the server that we should post our data to
def remote_method_uri(method)
uri = "/agent_listener/#{PROTOCOL_VERSION}/#{control.license_key}/#{method}"
uri << "?run_id=#{@agent_id}" if @agent_id
uri
end
# Sets the user agent for connections to the server, to
# conform with the HTTP spec and allow for debugging. Includes
# the ruby version and also zlib version if available since
# that may cause corrupt compression if there is a problem.
def user_agent
ruby_description = ''
# note the trailing space!
ruby_description << "(ruby #{::RUBY_VERSION} #{::RUBY_PLATFORM}) " if defined?(::RUBY_VERSION) && defined?(::RUBY_PLATFORM)
zlib_version = ''
zlib_version << "zlib/#{Zlib.zlib_version}" if defined?(::Zlib) && Zlib.respond_to?(:zlib_version)
"NewRelic-RubyAgent/#{NewRelic::VERSION::STRING} #{ruby_description}#{zlib_version}"
end
# send a message via post to the actual server. This attempts
# to automatically compress the data via zlib if it is large
# enough to be worth compressing, and handles any errors the
# server may return
def invoke_remote(method, *args)
now = Time.now
#determines whether to zip the data or send plain
post_data, encoding = compress_data(args)
response = send_request({:uri => remote_method_uri(method), :encoding => encoding, :collector => collector, :data => post_data})
# raises the right exception if the remote server tells it to die
return check_for_exception(response)
rescue NewRelic::Agent::ForceRestartException => e
log.info e.message
raise
rescue SystemCallError, SocketError => e
# These include Errno connection errors
raise NewRelic::Agent::ServerConnectionException, "Recoverable error connecting to the server: #{e}"
ensure
NewRelic::Agent.instance.stats_engine.get_stats_no_scope('Supportability/invoke_remote').record_data_point((Time.now - now).to_f)
NewRelic::Agent.instance.stats_engine.get_stats_no_scope('Supportability/invoke_remote/' + method.to_s).record_data_point((Time.now - now).to_f)
end
def save_or_transmit_data
if NewRelic::DataSerialization.should_send_data?
log.debug "Sending data to New Relic Service"
NewRelic::Agent.load_data unless NewRelic::Control.instance.disable_serialization?
harvest_and_send_errors
harvest_and_send_slowest_sample
harvest_and_send_slowest_sql
harvest_and_send_timeslice_data
else
log.debug "Serializing agent data to disk"
NewRelic::Agent.save_data
end
rescue => e
NewRelic::Control.instance.disable_serialization = true
NewRelic::Control.instance.log.warn("Disabling serialization: #{e.message}")
retry_count ||= 0
retry_count += 1
retry unless retry_count > 1
raise e
end
# This method contacts the server to send remaining data and
# let the server know that the agent is shutting down - this
# allows us to do things like accurately set the end of the
# lifetime of the process
#
# If this process comes from a parent process, it will not
# disconnect, so that the parent process can continue to send data
def graceful_disconnect
if @connected
begin
@request_timeout = 10
save_or_transmit_data
if @connected_pid == $$
log.debug "Sending New Relic service agent run shutdown message"
invoke_remote :shutdown, @agent_id, Time.now.to_f
else
log.debug "This agent connected from parent process #{@connected_pid}--not sending shutdown"
end
log.debug "Graceful disconnect complete"
rescue Timeout::Error, StandardError
end
else
log.debug "Bypassing graceful disconnect - agent not connected"
end
end
end
extend ClassMethods
include InstanceMethods
include BrowserMonitoring
end
end
end