logicminds/haproxy_manager

HAProxy Management API in Ruby.

HaProxy Manager

Haproxy provides ways to add and remove servers on the fly and a lot of other things. This gem lets you use that via a nice ruby API, so that it can be used in applications for deployments testing and gathering statistics.

This was extracted out of our rolling deployment scheme.

Prerequsites

For this to work haproxy

• Version 1.4 and above

• Should be running with the following configuration.

  stats socket /home/ubuntu/haproxysock level admin

  It means that haproxy will open a socket at /home/ubuntu/haproxysock. You can specify the level to use. We use admin. But I believe operator/admin is needed for the enable/disable/setting weights to work correctly.

Installation

Install the latest version of the gem with the following command...

  $ gem install haproxy_manager

  require "haproxy_manager"

Gemfile in Rails app

  gem "haproxy_manger", :require => false

Add the following where approporiate(eg. deploy.rb) require "haproxy_manager"

Release Notes

Version 0.2 opens up a bunch of new possibilities by allowing the user to interact with the backend or server object directly. Additionally the API is now more object oriented. Example:

serverobj.disable('foo-farm')

# get the stats for the server
serverobj.stats

# use any stat name and get value for all backends and calculate total across all backends
serverobj.smax  => {"foo-farm/bin"=>"34839081", "foo-https-farm/bin"=>"2577996", "total"=>37417077}

API

haproxy = HAProxyManager::Instance.new ('path to haproxy socket')



# New API Commands 0.2 API
haproxy.backend_instances  # Returns a hash of backend instances where the backend name is the key
haproxy.server_instances  # Returns a hash of server instances where the server name is the key

# New Backend API  (See class for more info)
foo_farm = haproxy.backend_instances('foo-farm')
foo_farm_servers = foo_farm.servers
foo_farm.up?  # returns the status of the backend
foo_farm.up_count  # returns the number of servers up in the backend
foo_farm.disable  # disable the entire backend
foo_farm.smax     # returns the value of smax for the backend (uses method missing)
foo_farm.bin       # returns the value of bytes in for the backend (uses method missing)

# New Server API  (See class for more info)
# because the server can be used in multiple backends many methods require the backend name to be passed in
all_servers = haproxy.server_instances
foo_farm_servers = haproxy.backend_instances('foo-farm').servers
foo_farm_servers.each do | name, server|
   puts "Info for #{server.name} = #{server.status('foo-farm')}"
   puts "Backends: #{server.backends.join("\n")}"
   puts "#{server.weight('foo-farm')"
   puts "#{server.smax}"
end

# New Hapsocket API 0.2 API
# The socket class has been moved to its own file and a new Class method has been added to determine if the socket is
# available should you need to determine if the socket can be opened
HAPSocket.available?('/home/haproxy/sockets/socketname')  # returns boolean

# below is a list of API calls that were used primarly in the 0.1 API but are still valid in 0.2 API
haproxy.backends # Lists all the backends available
haproxy.servers("foo-farm")  # List all the servers available in the given backend

haproxy.disable("preprod-app", "foo-farm") # Disables a server in a specific farm
haproxy.disable("preprod-app") # Disables a server with a given name in all the available backends


haproxy.enable("preprod-app", "foo-farm") # Enables a server in a specific farm
haproxy.enable("preprod-app") # Enables a server with a given name in all the available backends

haproxy.weight("preprod-app", "foo-farm", "10") # Sets the weight to 10. The value can be between 0 - 255
haproxy.weight("preprod-app", "foo-farm", "10%") # Reduces the weight of the server by 10%(of the value specified in the config)
haproxy.weight("preprod-app", "foo-farm", "0%") # Reduces the weight of the server to 0. Useful for disabling the server.
haproxy.weight("preprod-app", "foo-farm", "100%") # Increases the weight to the original configuration value. useful to bring the server back up after reducing the weight to 0%

haproxy.weight("preprod-app", "foo-farm") # Returns the current weights setting. The response is something like this.
{current => 10, initial=> 12}


haproxy.info # provides information about the haproxy setup. The following is how it looks like. Most fields are self describing.
{"Name" =>  "HAProxy", "Version" =>  "1.5-dev11", "Release_date" =>  "2012/06/04", "Nbproc" =>  "1", "Process_num" =>  "1", "Pid" =>  "4084", "Uptime" =>  "58d 3h50m53s", "Uptime_sec" => "5025053", "Memmax_MB" =>  "0", "Ulimit-n" =>  "40029", "Maxsock" =>  "40029", "Maxconn" =>  "20000", "Hard_maxconn" =>  "20000", "Maxpipes" => "0", "CurrConns" => "0", "PipesUsed" => "0", "PipesFree" => " 0", "ConnRate" => " 0", "ConnRateLimit" => " 0", "MaxConnRate" => " 69", "Tasks" => " 10", "Run_queue" => " 1", "Idle_pct" => "100", "node" => " The server name", "description" => "Our Awesome Load balancer"}

haproxy.reset_counters # Clears HAProxy counters. Except Global counters
haproxy.reset_counters(:all) # Clears All HAProxy counters. This is the equivalent of a restart

haproxy.stats # Retrives the HAProxy stats from the server. The result looks something like this.

{"foo-farm"=>
  {"FRONTEND"=>{"qcur"=>"", "qmax"=>"", "scur"=>"0", "smax"=>"150", "slim"=>"2000", "stot"=>"165893", "bin"=>"38619996", "bout"=>"3233457381", "dreq"=>"0", "dresp"=>"0", "ereq"=>"6504", "econ"=>"", "eresp"=>"", "wretr"=>"", "wredis"=>"", "status"=>"OPEN", "weight"=>"", "act"=>"", "bck"=>"", "chkfail"=>"", "chkdown"=>"", "lastchg"=>"", "downtime"=>"", "qlimit"=>"", "pid"=>"1", "iid"=>"1", "sid"=>"0", "throttle"=>"", "lbtot"=>"", "tracked"=>"", "type"=>"0", "rate"=>"0", "rate_lim"=>"0", "rate_max"=>"69", "check_status"=>"", "check_code"=>"", "check_duration"=>"", "hrsp_1xx"=>"0", "hrsp_2xx"=>"136147", "hrsp_3xx"=>"2128", "hrsp_4xx"=>"6654", "hrsp_5xx"=>"20955", "hrsp_other"=>"9", "hanafail"=>"", "req_rate"=>"0", "req_rate_max"=>"144", "req_tot"=>"165893", "cli_abrt"=>nil, "srv_abrt"=>nil}, 

  "preprod-app"=>{"qcur"=>"0", "qmax"=>"9", "scur"=>"0", "smax"=>"60", "slim"=>"60", "stot"=>"139066", "bin"=>"34839081", "bout"=>"3222850212", "dreq"=>"", "dresp"=>"0", "ereq"=>"", "econ"=>"3", "eresp"=>"725", "wretr"=>"0", "wredis"=>"0", "status"=>"UP", "weight"=>"10", "act"=>"1", "bck"=>"0", "chkfail"=>"583", "chkdown"=>"148", "lastchg"=>"10893", "downtime"=>"257935", "qlimit"=>"", "pid"=>"1", "iid"=>"1", "sid"=>"1", "throttle"=>"", "lbtot"=>"114847", "tracked"=>"", "type"=>"2", "rate"=>"0", "rate_lim"=>"", "rate_max"=>"88", "check_status"=>"L7OK", "check_code"=>"200", "check_duration"=>"150", "hrsp_1xx"=>"0", "hrsp_2xx"=>"135827", "hrsp_3xx"=>"2128", "hrsp_4xx"=>"147", "hrsp_5xx"=>"230", "hrsp_other"=>"0", "hanafail"=>"0", "req_rate"=>"", "req_rate_max"=>"", "req_tot"=>"", "cli_abrt"=>"20", "srv_abrt"=>"11"},

  "preprod-bg"=>{"qcur"=>"0", "qmax"=>"0", "scur"=>"0", "smax"=>"3", "slim"=>"30", "stot"=>"31", "bin"=>"14333", "bout"=>"380028", "dreq"=>"", "dresp"=>"0", "ereq"=>"", "econ"=>"0", "eresp"=>"9", "wretr"=>"4", "wredis"=>"2", "status"=>"DOWN", "weight"=>"5", "act"=>"1", "bck"=>"0", "chkfail"=>"4", "chkdown"=>"10", "lastchg"=>"2538799", "downtime"=>"4603702", "qlimit"=>"", "pid"=>"1", "iid"=>"1", "sid"=>"2", "throttle"=>"", "lbtot"=>"6", "tracked"=>"", "type"=>"2", "rate"=>"0", "rate_lim"=>"", "rate_max"=>"2", "check_status"=>"L4CON", "check_code"=>"", "check_duration"=>"0", "hrsp_1xx"=>"0", "hrsp_2xx"=>"16", "hrsp_3xx"=>"0", "hrsp_4xx"=>"0", "hrsp_5xx"=>"0", "hrsp_other"=>"0", "hanafail"=>"0", "req_rate"=>"", "req_rate_max"=>"", "req_tot"=>"", "cli_abrt"=>"1", "srv_abrt"=>"0"}, "preprod-test"=>{"qcur"=>"0", "qmax"=>"0", "scur"=>"0", "smax"=>"0", "slim"=>"30", "stot"=>"0", "bin"=>"0", "bout"=>"0", "dreq"=>"", "dresp"=>"0", "ereq"=>"", "econ"=>"0", "eresp"=>"0", "wretr"=>"0", "wredis"=>"0", "status"=>"DOWN", "weight"=>"5", "act"=>"1", "bck"=>"0", "chkfail"=>"0", "chkdown"=>"1", "lastchg"=>"5102839", "downtime"=>"5102839", "qlimit"=>"", "pid"=>"1", "iid"=>"1", "sid"=>"3", "throttle"=>"", "lbtot"=>"0", "tracked"=>"", "type"=>"2", "rate"=>"0", "rate_lim"=>"", "rate_max"=>"0", "check_status"=>"L4CON", "check_code"=>"", "check_duration"=>"0", "hrsp_1xx"=>"0", "hrsp_2xx"=>"0", "hrsp_3xx"=>"0", "hrsp_4xx"=>"0", "hrsp_5xx"=>"0", "hrsp_other"=>"0", "hanafail"=>"0", "req_rate"=>"", "req_rate_max"=>"", "req_tot"=>"", "cli_abrt"=>"0", "srv_abrt"=>"0"},

  "BACKEND"=>{"qcur"=>"0", "qmax"=>"84", "scur"=>"0", "smax"=>"150", "slim"=>"200", "stot"=>"159082", "bin"=>"38619996", "bout"=>"3233457381", "dreq"=>"0", "dresp"=>"0", "ereq"=>"", "econ"=>"19991", "eresp"=>"734", "wretr"=>"4", "wredis"=>"2", "status"=>"UP", "weight"=>"10", "act"=>"1", "bck"=>"0", "chkfail"=>"", "chkdown"=>"148", "lastchg"=>"10893", "downtime"=>"300268", "qlimit"=>"", "pid"=>"1", "iid"=>"1", "sid"=>"0", "throttle"=>"", "lbtot"=>"114853", "tracked"=>"", "type"=>"1", "rate"=>"0", "rate_lim"=>"", "rate_max"=>"144", "check_status"=>"", "check_code"=>"", "check_duration"=>"", "hrsp_1xx"=>"0", "hrsp_2xx"=>"135843", "hrsp_3xx"=>"2128", "hrsp_4xx"=>"147", "hrsp_5xx"=>"20955", "hrsp_other"=>"9", "hanafail"=>"", "req_rate"=>"", "req_rate_max"=>"", "req_tot"=>"", "cli_abrt"=>"21", "srv_abrt"=>"11"}}}