mruby で mackerel のプラグインを作るはなし

mruby で mackerel のプラグインを作るはなし

1. 1. mruby で mackerel の プラグインを作るはなし 今やるなら mruby
2. 2. self.introduce => { name: “SHIBATA Hiroshi”, nickname: “hsbt”, title: “Chief engineer at GMO Pepabo, Inc.”, commit_bits: [“ruby”, “rake”, “rubygems”, “rdoc”, “tdiary”, “hiki”, “railsgirls”, “railsgirls-jp”, …], sites: [“hsbt.org”, ruby-lang.org”, “rubyci.com”, “railsgirls.com”, “railsgirls.jp”], }
3. 3. What’s mackerel plugin? time series data monitoring item
4. 4. mackerel plugin format •time series data •tab separated value at stdout •monitoring item •nagios compatible results with exit status
5. 5. Write cli tool using mruby-cli see. https://github.com/hone/mruby-cli 1. Edit `build_config.rb` in top-level directory of mruby-cli 2. write mruby code into mrblib 3. build cli binary with docker or your development platform I think it’s too easily using mruby and mruby-redis at first.
6. 6. NoMethodError… > r = Redis.new '127.0.0.1', 6379 => #<Redis:0x7fa109806230> > r.scard (mirb):3: undefined method 'scard' for #<Redis:0x7fa109806230> (NoMethodError) > r.smember (mirb):4: undefined method 'smember' for #<Redis:0x7fa109806230> (NoMethodError) ??? … mruby-redis is not support `Set` type function in redis.
7. 7. We can make it
8. 8. Reading mruby-redis Checking out “https://github.com/matsumoto-r/mruby-redis” and open Rakefile MRUBY_CONFIG=File.expand_path(ENV["MRUBY_CONFIG"] || "build_config.rb") (snip) file :mruby do (snip) sh "git clone --depth=1 git://github.com/mruby/mruby.git" end desc "compile binary" task :compile => :mruby do sh "cd mruby && MRUBY_CONFIG=#{MRUBY_CONFIG} rake all" end (snip)
9. 9. build_config.rb MRuby::Build.new do |conf| # load specific toolchain settings toolchain :gcc (snip) conf.gembox 'default' conf.gem File.expand_path(File.dirname(__FILE__)) conf.gem :github => 'matsumoto-r/mruby-sleep' (snip) end
10. 10. Static link with hiredis MRuby::Gem::Specification.new('mruby-redis') do |spec| (snip) hiredis_dir = "#{build_dir}/hiredis" (snip) if ! File.exists? hiredis_dir Dir.chdir(build_dir) do e = {} run_command e, 'git clone git://github.com/redis/hiredis.git' end end (snip) spec.cc.include_paths << "#{hiredis_dir}/include" spec.linker.flags_before_libraries << “#{hiredis_dir}/lib/libhiredis.a" (snip) end
11. 11. Initialization point of native ext of mrbgem see doc/guides/mrbgems.md on mruby/mruby In src/mruby_redis.h on matsumoto-r/mruby-redis mrb_YOURGEMNAME_gem_init(mrb_state) ex. ruby-redis: mrb_mruby_redis_gem_init(mrb_state) #ifndef MRB_REDIS_H #define MRB_REDIS_H void mrb_mruby_redis_gem_init(mrb_state *mrb); #endif
12. 12. Basic pattern of mruby class in C void mrb_mruby_redis_gem_init(mrb_state *mrb) { struct RClass *redis; redis = mrb_define_class(mrb, "Redis", mrb->object_class); mrb_define_class_under(mrb, redis, "ConnectionError", E_RUNTIME_ERROR); mrb_define_method(mrb, redis, "initialize", mrb_redis_connect, MRB_ARGS_ANY()); mrb_define_method(mrb, redis, "select", mrb_redis_select, MRB_ARGS_REQ(1)); (snip) mrb_define_method(mrb, redis, "flushdb", mrb_redis_flushdb, MRB_ARGS_NONE()); (snip) }
13. 13. mrb_value mrb_redis_llen(mrb_state *mrb, mrb_value self) { mrb_value key; mrb_int integer; redisContext *rc = DATA_PTR(self); mrb_get_args(mrb, "o", &key); redisReply *rr = redisCommand(rc,"LLEN %s", mrb_str_to_cstr(mrb, key)); integer = rr->integer; freeReplyObject(rr); return mrb_fixnum_value(integer); } Write instance methods using C
14. 14. Implementation of “scard” command “scard" received key of target Set. It’s same as “llen” Replaced “LLEN” to “SCARD” SCARD return integer value of Set length mrb_get_args(mrb, "o", &key); redisReply *rr = redisCommand(rc,"SCARD %s", mrb_str_to_cstr(mrb, key)); integer = rr->integer; return mrb_fixnum_value(integer); mrb_define_method(mrb, redis, "scard", mrb_redis_scard, MRB_ARGS_REQ(1));
15. 15. Implementation of “smember” command mrb_value mrb_redis_smembers(mrb_state *mrb, mrb_value self) { int i; mrb_value array, key; redisContext *rc = DATA_PTR(self); mrb_get_args(mrb, "o", &key); redisReply *rr = redisCommand(rc, "SMEMBERS %s", mrb_str_to_cstr(mrb, key)); if (rr->type == REDIS_REPLY_ARRAY) { array = mrb_ary_new(mrb); for (i = 0; i < rr->elements; i++) { mrb_ary_push(mrb, array, mrb_str_new(mrb, rr->element[i]->str, rr->element[i]->len)); } } else { freeReplyObject(rr); return mrb_nil_value(); } freeReplyObject(rr); return array; }
16. 16. mackerel-plugin-sidekiq-job-count https://github.com/hsbt/mackerel-plugin-sidekiq-job-count def __main__(argv) if argv[1] == "version" puts "v#{SidekiqJobCount::VERSION}" else r = Redis.new argv[1], argv[2].to_i namespace = argv[3] key = "" key += "#{namespace}:" if namespace key += 'queues' queues = r.smembers key enqueued = queues.map{|queue| "#{key[0...-1]}:#{queue}" }.map{|k| r.llen k }.inject(0){|s, v| s + v} r.close puts "sidekiq_job_count.enqueuedt#{enqueued}t#{Time.now.to_i}" end end
17. 17. It works!!1 [user@manage001 ~]$ /usr/local/bin/mackerel-plugin-sidekiq-job-count redis_host_name 6379 sidekiq sidekiq_job_count.enqueued 0 1446624944