Add placement group control to the pool resource.

providers/pool.rb

@@ -13,7 +13,17 @@ def whyrun_supported?
 
 action :create do
   if @current_resource.exists
-    Chef::Log.info "#{@new_resource} already exists - nothing to do."
+    if @current_resource.pg_num == @new_resource.pg_num
+      Chef::Log.info "#{@new_resource} already exists - nothing to do."
+    else
+      Chef::Log.info "#{@new_resource} already exists, with different pg_num."
+      converge_by("Setting pg_num for #{@new_resource}") do
+        set_pg_num(@new_resource.name, @new_resource.pg_num)
+        while get_pgp_num(@new_resource.name) != @new_resource.pg_num
+          set_pgp_num(@new_resource.name, @new_resource.pg_num)
+        end
+      end
+    end
   else
     converge_by("Creating #{@new_resource}") do
       create_pool
@@ -35,6 +45,8 @@ def load_current_resource
   @current_resource = Chef::Resource::CephPool.new(@new_resource.name)
   @current_resource.name(@new_resource.name)
   @current_resource.exists = pool_exists?(@current_resource.name)
+  @current_resource.pg_num = get_pg_num(@current_resource.name) || 0
+  @current_resource.pgp_num = get_pgp_num(@current_resource.name) || 0
 end
 
 def create_pool
@@ -56,6 +68,36 @@ def delete_pool
   Chef::Log.debug "Pool deleted: #{cmd.stderr}"
 end
 
+def set_pg_num(name, pg_num)
+  cmd_text = "ceph osd pool set #{name} pg_num #{pg_num}"
+  cmd = Mixlib::ShellOut.new(cmd_text)
+  cmd.run_command
+  cmd.error!
+  Chef::Log.debug "Placement Groups Set: #{cmd.stderr}"
+end
+
+def set_pgp_num(name, pg_num)
+  cmd_text = "ceph osd pool set #{name} pgp_num #{pg_num}"
+  cmd = Mixlib::ShellOut.new(cmd_text)
+  cmd.run_command
+  cmd.error!
+  Chef::Log.debug "Placement Groups Set: #{cmd.stderr}"
+end
+
+def get_pg_num(name)
+  cmd = Mixlib::ShellOut.new("ceph osd pool get #{name} pg_num")
+  cmd.run_command
+  cmd.error!
+  cmd.stdout.split(' ')[1].to_i
+end
+
+def get_pgp_num(name)
+  cmd = Mixlib::ShellOut.new("ceph osd pool get #{name} pgp_num")
+  cmd.run_command
+  cmd.error!
+  cmd.stdout.split(' ')[1].to_i
+end
+
 def pool_exists?(name)
   cmd = Mixlib::ShellOut.new("ceph osd pool get #{name} size")
   cmd.run_command

resources/pool.rb

@@ -12,6 +12,7 @@
 
 # The total number of placement groups for the pool.
 attribute :pg_num, :kind_of => Integer, :required => true
+attribute :pgp_num, kind_of: Integer, required: false
 
 # Optional arguments for pool creation
 attribute :create_options, :kind_of => String