lib/fluent/plugin/elasticsearch_index_template.rb
require 'fluent/error'
require_relative './elasticsearch_error'
module Fluent::ElasticsearchIndexTemplate
def get_template(template_file)
if !File.exist?(template_file)
raise "If you specify a template_name you must specify a valid template file (checked '#{template_file}')!"
end
file_contents = IO.read(template_file).gsub(/\n/,'')
JSON.parse(file_contents)
end
def get_custom_template(template_file, customize_template)
if !File.exist?(template_file)
raise "If you specify a template_name you must specify a valid template file (checked '#{template_file}')!"
end
file_contents = IO.read(template_file).gsub(/\n/,'')
customize_template.each do |key, value|
file_contents = file_contents.gsub(key,value.downcase)
end
JSON.parse(file_contents)
end
def template_exists?(name, host = nil)
if @use_legacy_template
client(host).indices.get_template(:name => name)
else
client(host).indices.get_index_template(:name => name)
end
return true
rescue TRANSPORT_CLASS::Transport::Errors::NotFound
return false
end
def host_unreachable_exceptions
if Gem::Version.new(::TRANSPORT_CLASS::VERSION) >= Gem::Version.new("8.0.0")
# elasticsearch-ruby 8.0.0's elastic-transport uses
# direct callable #host_unreachable_exceptions again.
client.transport.host_unreachable_exceptions
elsif Gem::Version.new(::TRANSPORT_CLASS::VERSION) >= Gem::Version.new("7.14.0")
# elasticsearch-ruby 7.14.0's elasticsearch-transport does not extends
# Elasticsearch class on Transport.
# This is why #host_unreachable_exceptions is not callable directly
# via transport (not transport's transport instance accessor) any more.
client.transport.transport.host_unreachable_exceptions
else
client.transport.host_unreachable_exceptions
end
end
def retry_operate(max_retries, fail_on_retry_exceed = true, catch_trasport_exceptions = true)
return unless block_given?
retries = 0
transport_errors = TRANSPORT_CLASS::Transport::Errors.constants.map{ |c| TRANSPORT_CLASS::Transport::Errors.const_get c } if catch_trasport_exceptions
begin
yield
rescue *host_unreachable_exceptions, *transport_errors, Timeout::Error => e
@_es = nil
@_es_info = nil
if retries < max_retries
retries += 1
wait_seconds = 2**retries
sleep wait_seconds
log.warn "Could not communicate to Elasticsearch, resetting connection and trying again. #{e.message}"
log.warn "Remaining retry: #{max_retries - retries}. Retry to communicate after #{wait_seconds} second(s)."
retry
end
message = "Could not communicate to Elasticsearch after #{retries} retries. #{e.message}"
log.warn message
raise Fluent::Plugin::ElasticsearchError::RetryableOperationExhaustedFailure,
message if fail_on_retry_exceed
end
end
def template_put(name, template, host = nil)
if @use_legacy_template
client(host).indices.put_template(:name => name, :body => template)
else
client(host).indices.put_index_template(:name => name, :body => template)
end
end
def indexcreation(index_name, host = nil)
client(host).indices.create(:index => index_name)
rescue TRANSPORT_CLASS::Transport::Error => e
if e.message =~ /"already exists"/ || e.message =~ /resource_already_exists_exception/
log.debug("Index #{index_name} already exists")
else
log.error("Error while index creation - #{index_name}", error: e)
end
end
def template_install(name, template_file, overwrite, enable_ilm = false, deflector_alias_name = nil, ilm_policy_id = nil, host = nil, target_index = nil, index_separator = '-')
inject_template_name = get_template_name(enable_ilm, name, deflector_alias_name)
if overwrite
template_put(inject_template_name,
enable_ilm ? inject_ilm_settings_to_template(deflector_alias_name,
target_index,
ilm_policy_id,
get_template(template_file),
index_separator) :
get_template(template_file), host)
log.debug("Template '#{inject_template_name}' overwritten with #{template_file}.")
return
end
if !template_exists?(inject_template_name, host)
template_put(inject_template_name,
enable_ilm ? inject_ilm_settings_to_template(deflector_alias_name,
target_index,
ilm_policy_id,
get_template(template_file),
index_separator) :
get_template(template_file), host)
log.info("Template configured, but no template installed. Installed '#{inject_template_name}' from #{template_file}.")
else
log.debug("Template '#{inject_template_name}' configured and already installed.")
end
end
def template_custom_install(template_name, template_file, overwrite, customize_template, enable_ilm, deflector_alias_name, ilm_policy_id, host, target_index, index_separator)
template_custom_name = get_template_name(enable_ilm, template_name, deflector_alias_name)
custom_template = if enable_ilm
inject_ilm_settings_to_template(deflector_alias_name,
target_index,
ilm_policy_id,
get_custom_template(template_file,
customize_template),
index_separator)
else
get_custom_template(template_file, customize_template)
end
if overwrite
template_put(template_custom_name, custom_template, host)
log.info("Template '#{template_custom_name}' overwritten with #{template_file}.")
else
if !template_exists?(template_custom_name, host)
template_put(template_custom_name, custom_template, host)
log.info("Template configured, but no template installed. Installed '#{template_custom_name}' from #{template_file}.")
else
log.debug("Template '#{template_custom_name}' configured and already installed.")
end
end
end
def get_template_name(enable_ilm, template_name, deflector_alias_name)
enable_ilm ? deflector_alias_name : template_name
end
def inject_ilm_settings_to_template(deflector_alias, target_index, ilm_policy_id, template, index_separator)
log.debug("Overwriting index patterns when Index Lifecycle Management is enabled.")
template['index_patterns'] = "#{target_index}#{index_separator}*"
if @use_legacy_template
template.delete('template') if template.include?('template')
# Prepare settings Hash
if !template.key?('settings')
template['settings'] = {}
end
if template['settings'] && (template['settings']['index.lifecycle.name'] || template['settings']['index.lifecycle.rollover_alias'])
log.debug("Overwriting index lifecycle name and rollover alias when Index Lifecycle Management is enabled.")
end
template['settings'].update({ 'index.lifecycle.name' => ilm_policy_id, 'index.lifecycle.rollover_alias' => deflector_alias})
template['order'] = template['order'] ? template['order'] + target_index.count(index_separator) + 1 : 51 + target_index.count(index_separator)
else
# Prepare template.settings Hash
if !template['template'].key?('settings')
template['template']['settings'] = {}
end
if template['template']['settings'] && (template['template']['settings']['index.lifecycle.name'] || template['template']['settings']['index.lifecycle.rollover_alias'])
log.debug("Overwriting index lifecycle name and rollover alias when Index Lifecycle Management is enabled.")
end
template['template']['settings'].update({ 'index.lifecycle.name' => ilm_policy_id, 'index.lifecycle.rollover_alias' => deflector_alias})
template['priority'] = template['priority'] ? template['priority'] + target_index.count(index_separator) + 1 : 101 + target_index.count(index_separator)
end
template
end
def create_rollover_alias(target_index, rollover_index, deflector_alias_name, app_name, index_date_pattern, index_separator, enable_ilm, ilm_policy_id, ilm_policy, ilm_policy_overwrite, host)
# ILM request to create alias.
if rollover_index || enable_ilm
if !client.indices.exists_alias(:name => deflector_alias_name)
if @logstash_format
index_name_temp = '<'+target_index+'-000001>'
else
if index_date_pattern.empty?
index_name_temp = '<'+target_index.downcase+index_separator+app_name.downcase+'-000001>'
else
index_name_temp = '<'+target_index.downcase+index_separator+app_name.downcase+'-{'+index_date_pattern+'}-000001>'
end
end
indexcreation(index_name_temp, host)
body = rollover_alias_payload(deflector_alias_name)
client.indices.put_alias(:index => index_name_temp, :name => deflector_alias_name,
:body => body)
log.info("The alias '#{deflector_alias_name}' is created for the index '#{index_name_temp}'")
else
log.debug("The alias '#{deflector_alias_name}' is already present")
end
# Create ILM policy if rollover indices exist.
if enable_ilm
if ilm_policy.empty?
setup_ilm(enable_ilm, ilm_policy_id)
else
setup_ilm(enable_ilm, ilm_policy_id, ilm_policy, ilm_policy_overwrite)
end
end
else
log.debug("No index and alias creation action performed because rollover_index or enable_ilm is set to: '#{rollover_index}', '#{enable_ilm}'")
end
end
def templates_hash_install(templates, overwrite)
templates.each do |key, value|
template_install(key, value, overwrite)
end
end
def rollover_alias_payload(rollover_alias)
{
'aliases' => {
rollover_alias => {
'is_write_index' => true
}
}
}
end
end