a number of improvements and fixes to the new mms-agent recipe:

- fix the cookbook name in runit
- adds 2 new attributes: mongodb.mms_agent.{install_dir, log_dir} to
  customize the agent
- forces the use of the standard community runit cookbook
- only restarts the agent service if a change has been detected
- sets two new 'dynamic' attributes for reference:
  mongodb.mms_agent.{version, checksum}

note that the last (bounce on change) required quite a bit of extra work
because it always downloads the zip; most of this can be removed when
the issue is resolved by the mms mongo team

Berksfile.lock

@@ -4,11 +4,19 @@
       "path": "."
     },
     "apt": {
-      "locked_version": "1.8.4",
-      "constraint": ">= 1.8.2"
+      "locked_version": "2.1.1"
+    },
+    "python": {
+      "locked_version": "1.4.0"
+    },
+    "build-essential": {
+      "locked_version": "1.4.0"
     },
     "yum": {
-      "locked_version": "2.1.0"
+      "locked_version": "2.3.0"
+    },
+    "runit": {
+      "locked_version": "1.3.0"
     }
   }
 }

README.md

@@ -59,6 +59,8 @@ For examples see the USAGE section below.
 * `mongodb[:replicaset_name]` - Define name of replicatset
 * `mongodb[:mms_agent][:api_key]` - MMS Agent API Key
 * `mongodb[:mms_agent][:secret_key]` - MMS Agent API Key
+* `mongodb[:mms_agent][:install_dir]` - Location to install the agent
+* `mongodb[:mms_agent][:log_dir]` - Location to write the agent logfile. If this is a relative path, it's relative to where the service is run (via runit), e.g. set to './main'
 
 # USAGE:
 

attributes/mms_agent.rb

@@ -1,2 +1,5 @@
-default['mongodb']['mms_agent']['api_key'] = ''
-default['mongodb']['mms_agent']['secret_key'] = ''
+default[:mongodb][:mms_agent][:api_key] = ""
+default[:mongodb][:mms_agent][:secret_key] = ""
+
+default[:mongodb][:mms_agent][:install_dir] = "/usr/local/share"
+default[:mongodb][:mms_agent][:log_dir] = "#{node[:mongodb][:logpath]}/agent"

metadata.rb

@@ -11,11 +11,11 @@
 recipe "mongodb::configserver", "Installs and configures a configserver for mongodb sharding"
 recipe "mongodb::shard", "Installs and configures a single shard"
 recipe "mongodb::replicaset", "Installs and configures a mongodb replicaset"
+recipe "mongodb::mms-agent", "Installs and configures a Mongo Management Service agent"
 
 depends "apt", ">= 1.8.2"
-depends "apt"
 depends "python"
-depends "runit"
+depends "runit", ">= 1.1.6"
 depends "yum"
 
 %w{ ubuntu debian freebsd centos redhat fedora amazon scientific}.each do |os|

recipes/mms-agent.rb

@@ -9,52 +9,86 @@
 include_recipe 'python'
 
 require 'fileutils'
+chef_gem 'rubyzip'
 
 # munin-node for hardware info
 package 'munin-node'
+# python dependencies
+python_pip 'pymongo'
 
-# download
+# download, and unzip if it's changed
 package 'unzip'
 remote_file '/tmp/10gen-mms-agent.zip' do
   source 'https://mms.10gen.com/settings/10gen-mms-agent.zip'
+  # irrelevant because of https://jira.mongodb.org/browse/MMSSUPPORT-2258
+  checksum node.mongodb.mms_agent.checksum if node.mongodb.mms_agent.key?(:checksum)
+  notifies :run, "bash[unzip 10gen-mms-agent]", :immediately
 end
-
-# unzip
 bash 'unzip 10gen-mms-agent' do
   cwd '/tmp/'
-  code <<-EOH
-    unzip -o -d /usr/local/share/ ./10gen-mms-agent.zip
-  EOH
-  not_if { File.exist?('/usr/local/share/mms-agent') }
+  code "rm -rf #{node.mongodb.mms_agent.install_dir} && unzip -o -d #{node.mongodb.mms_agent.install_dir} /tmp/10gen-mms-agent.zip"
+  action :nothing
+  only_if {
+    def checksum_zip_contents(zipfile)
+      require 'zip/filesystem'
+      require 'digest'
+
+      files = Zip::File.open(zipfile).collect.reject{|f| f.name_is_directory?}.sort
+      content = files.map{|f| f.get_input_stream.read}.join
+      Digest::SHA256.hexdigest content
+    end
+    new_checksum = checksum_zip_contents('/tmp/10gen-mms-agent.zip')
+    existing_checksum = node.mongodb.mms_agent.key?(:checksum) ? node.mongodb.mms_agent.checksum : 'NONE'
+    Chef::Log.debug "new checksum = #{new_checksum}, expected = #{existing_checksum}"
+
+    should_install = !File.exist?("#{node.mongodb.mms_agent.install_dir}/settings.py") || new_checksum != existing_checksum
+    # update the expected checksum in chef, for reference
+    node.default.mongodb.mms_agent.checksum = new_checksum
+    should_install
+  }
 end
 
-# install pymongo
-python_pip 'pymongo' do
-  action :install
+# runit and agent logging
+directory node.mongodb.mms_agent.log_dir do
+  action :create
+  recursive true
+end
+include_recipe 'runit::default'
+mms_agent_service = runit_service 'mms-agent' do
+  template_name 'mms-agent'
+  cookbook 'mongodb'
+  options({
+    :mms_agent_install_dir => node.mongodb.mms_agent.install_dir,
+    :mms_agent_log_dir => node.mongodb.mms_agent.log_dir
+  })
+  action :nothing
 end
 
-# modify settings.py
+# update settings.py and restart the agent if there were any key changes
 ruby_block 'modify settings.py' do
   block do
+    Chef::Log.warn "Found empty mms_agent.api_key or mms_agent.secret_key attributes" if node.mongodb.mms_agent.api_key.empty? || node.mongodb.mms_agent.secret_key.empty?
+
     orig_s = ''
-    open('/usr/local/share/mms-agent/settings.py') { |f|
+    open("#{node.mongodb.mms_agent.install_dir}/mms-agent/settings.py") { |f|
       orig_s = f.read
     }
     s = orig_s
     s = s.gsub(/mms\.10gen\.com/, 'mms.10gen.com')
-    s = s.gsub(/@API_KEY@/, node['mongodb']['mms_agent']['api_key'])
-    s = s.gsub(/@SECRET_KEY@/, node['mongodb']['mms_agent']['secret_key'])
+    s = s.gsub(/mms_key = ".*"/, "mms_key = \"#{node['mongodb']['mms_agent']['api_key']}\"")
+    s = s.gsub(/secret_key = ".*"/, "secret_key = \"#{node['mongodb']['mms_agent']['secret_key']}\"")
     if s != orig_s
-      open('/usr/local/share/mms-agent/settings.py','w') { |f|
+      Chef::Log.debug "Settings changed, overwriting and restarting service"
+      open("#{node.mongodb.mms_agent.install_dir}/mms-agent/settings.py", 'w') { |f|
         f.puts(s)
       }
+
+      # update the agent version in chef, for reference
+      /settingsAgentVersion = "(?<mms_agent_version>.*)"/ =~ s
+      node.default.mongodb.mms_agent.version = mms_agent_version
+
+      notifies :enable, mms_agent_service, :delayed
+      notifies :restart, mms_agent_service, :delayed
     end
   end
 end
-
-# runit
-runit_service 'mms-agent' do
-  template_name 'mms-agent'
-  cookbook 'mms-agent'
-  run_restart false
-end

templates/default/sv-mms-agent-log-run.erb

@@ -1,2 +1,3 @@
 #!/bin/sh
-exec svlogd -tt ./main
+
+exec svlogd -tt <%= @options[:mms_agent_log_dir] %>

templates/default/sv-mms-agent-run.erb

@@ -1,6 +1,6 @@
-#!/bin/bash
+#!/bin/sh
 
-cd /usr/local/share/mms-agent/
+cd <%= @options[:mms_agent_install_dir] %>
 
 exec 2>&1
-exec chpst -u root:root python /usr/local/share/mms-agent/agent.py 2>&1
+exec chpst -u root:root python <%= @options[:mms_agent_install_dir] %>/mms-agent/agent.py 2>&1