Add support for Arbiter pools

Signed-off-by: Shree Vatsa N <vatsa@kadalu.tech>

mgr/shard.lock

@@ -6,7 +6,7 @@ shards:
 
   crinja:
     git: https://github.com/straight-shoota/crinja.git
-    version: 0.8.0
+    version: 0.8.1
 
   db:
     git: https://github.com/crystal-lang/crystal-db.git
@@ -22,7 +22,7 @@ shards:
 
   kemal:
     git: https://github.com/kemalcr/kemal.git
-    version: 1.3.0
+    version: 1.4.0
 
   moana_types:
     path: ../types
@@ -38,7 +38,7 @@ shards:
 
   volgen:
     git: https://github.com/kadalu/volgen.git
-    version: 0.3.1
+    version: 0.4.1
 
   xattr:
     git: https://github.com/aravindavk/xattr-crystal.git

mgr/src/cmds/pool_create_parser.cr

@@ -178,6 +178,10 @@ module PoolRequestParser
         storage_units["replica"].size,
         storage_units["mirror"].size
       )
+    elsif storage_units["arbiter"].size == 3
+      grp_storage_units = storage_units["arbiter"]
+      dist_group.replica_count = 3
+      dist_group.arbiter_count = 1
     elsif storage_units["disperse"].size > 0 ||
           storage_units["data"].size > 0
       grp_storage_units = storage_units["disperse"] +
@@ -292,7 +296,12 @@ module PoolRequestParser
     # TODO: Pool name validations
 
     req.distribute_groups.each do |dist_grp|
-      if dist_grp.replica_count > 0 && dist_grp.storage_units.size != dist_grp.replica_count
+      replica_arbiter_dist_grp_size = dist_grp.replica_count
+      if dist_grp.arbiter_count > 0 && dist_grp.replica_count == 2
+        replica_arbiter_dist_grp_size += 1
+      end
+
+      if dist_grp.replica_count > 0 && dist_grp.storage_units.size != replica_arbiter_dist_grp_size
         raise InvalidPoolRequest.new(
           "Number of Storage units not matching #{dist_grp.replica_keyword} count"
         )

mgr/src/server/plugins/pool_utils.cr

@@ -299,6 +299,7 @@ def services_and_volfiles(req)
 
   # Client Volfile
   tmpl = volfile_get("client")
+
   client_volfile_content = Volgen.generate(tmpl, req.to_json, req.options)
 
   # SHD Volfile
@@ -309,7 +310,7 @@ def services_and_volfiles(req)
   end
 
   req.distribute_groups.each do |dist_grp|
-    dist_grp.storage_units.each do |storage_unit|
+    dist_grp.storage_units.each_with_index do |storage_unit, index|
       # Generate Service Unit
       service = StorageUnitService.new(req.name, storage_unit)
       services[storage_unit.node.name] = [] of MoanaTypes::ServiceUnit unless services[storage_unit.node.name]?
@@ -321,6 +322,13 @@ def services_and_volfiles(req)
       tmpl = volfile_get("storage_unit")
       storage_unit.volume.id = req.id
       storage_unit.volume.name = req.name
+
+      # Handle arbiter pools
+      # Mark every 3rd storage-unit as type arbiter if distribute group has arbiter count > 0
+      if dist_grp.arbiter_count > 0 && ((index + 1) % 3 == 0)
+        storage_unit.type = "arbiter"
+      end
+
       content = Volgen.generate(tmpl, storage_unit.to_json)
       volfiles[storage_unit.node.name] = [] of MoanaTypes::Volfile unless volfiles[storage_unit.node.name]?
       volfiles[storage_unit.node.name] << MoanaTypes::Volfile.new(service.id, content)

types/src/moana_types.cr

@@ -109,7 +109,9 @@ module MoanaTypes
     end
 
     def type
-      if @replica_count > 0
+      if @replica_count >= 2 && @arbiter_count == 1
+        "Arbiter"
+      elsif @replica_count > 0
         @replica_keyword == "mirror" ? "Mirror" : "Replicate"
       elsif @disperse_count > 0
         "Disperse"