summaryrefslogtreecommitdiff
path: root/provider_base/lib/macros/nodes.rb
diff options
context:
space:
mode:
Diffstat (limited to 'provider_base/lib/macros/nodes.rb')
-rw-r--r--provider_base/lib/macros/nodes.rb88
1 files changed, 88 insertions, 0 deletions
diff --git a/provider_base/lib/macros/nodes.rb b/provider_base/lib/macros/nodes.rb
new file mode 100644
index 00000000..0c6668a0
--- /dev/null
+++ b/provider_base/lib/macros/nodes.rb
@@ -0,0 +1,88 @@
+# encoding: utf-8
+
+##
+## node related macros
+##
+
+module LeapCli
+ module Macro
+
+ #
+ # the list of all the nodes
+ #
+ def nodes
+ global.nodes
+ end
+
+ #
+ # grab an environment appropriate provider
+ #
+ def provider
+ global.env(@node.environment).provider
+ end
+
+ #
+ # returns a list of nodes that match the same environment
+ #
+ # if @node.environment is not set, we return other nodes
+ # where environment is not set.
+ #
+ def nodes_like_me
+ nodes[:environment => @node.environment]
+ end
+
+ #
+ # returns a list of nodes that match the location name
+ # and environment of @node.
+ #
+ def nodes_near_me
+ if @node['location'] && @node['location']['name']
+ nodes_like_me['location.name' => @node.location.name]
+ else
+ nodes_like_me['location' => nil]
+ end
+ end
+
+ #
+ #
+ # picks a node out from the node list in such a way that:
+ #
+ # (1) which nodes picked which nodes is saved in secrets.json
+ # (2) when other nodes call this macro with the same node list, they are guaranteed to get a different node
+ # (3) if all the nodes in the pick_node list have been picked, remaining nodes are distributed randomly.
+ #
+ # if the node_list is empty, an exception is raised.
+ # if node_list size is 1, then that node is returned and nothing is
+ # memorized via the secrets.json file.
+ #
+ # `label` is needed to distinguish between pools of nodes for different purposes.
+ #
+ # TODO: more evenly balance after all the nodes have been picked.
+ #
+ def pick_node(label, node_list)
+ if node_list.any?
+ if node_list.size == 1
+ return node_list.values.first
+ else
+ secrets_key = "pick_node(:#{label},#{node_list.keys.sort.join(',')})"
+ secrets_value = @manager.secrets.retrieve(secrets_key, @node.environment) || {}
+ secrets_value[@node.name] ||= begin
+ node_to_pick = nil
+ node_list.each_node do |node|
+ next if secrets_value.values.include?(node.name)
+ node_to_pick = node.name
+ end
+ node_to_pick ||= secrets_value.values.shuffle.first # all picked already, so pick a random one.
+ node_to_pick
+ end
+ picked_node_name = secrets_value[@node.name]
+ @manager.secrets.set(secrets_key, secrets_value, @node.environment)
+ return node_list[picked_node_name]
+ end
+ else
+ raise ArgumentError.new('pick_node(node_list): node_list cannot be empty')
+ end
+ end
+
+ end
+end \ No newline at end of file