Class: Elastomer::Client::Cluster

Inherits:
Object
  • Object
show all
Defined in:
lib/elastomer/client/cluster.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(client) ⇒ Cluster

Create a new cluster client for making API requests that pertain to the cluster health and management.

client - Elastomer::Client used for HTTP requests to the server



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# File 'lib/elastomer/client/cluster.rb', line 16

def initialize( client )
  @client = client
end

Instance Attribute Details

#client ⇒ Object (readonly)

Returns the value of attribute client.



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# File 'lib/elastomer/client/cluster.rb', line 20

def client
  @client
end

Instance Method Details

#get_aliases(params = {}) ⇒ Object Also known as: aliases

Retrieve the current aliases. An :index name can be given (or an array of index names) to get just the aliases for those indexes. You can also use the alias name here since it is acting the part of an index.

params - Parameters Hash

:index - an index name or Array of index names
:name  - an alias name or Array of alias names

Examples

get_aliases
get_aliases( index: 'users' )

See www.elastic.co/guide/en/elasticsearch/reference/current/indices-aliases.html

Returns the response body as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 181

def get_aliases( params = {} )
  response = client.get "{/index}/_alias{/name}", params.merge(action: "cluster.get_aliases", rest_api: "indices.get_alias")
  response.body
end

#get_settings(params = {}) ⇒ Object Also known as: settings

Cluster wide settings that have been modified via the update API.

params - Parameters Hash

See www.elastic.co/guide/en/elasticsearch/reference/current/cluster-update-settings.html

Returns the response as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 103

def get_settings( params = {} )
  response = client.get "/_cluster/settings", params.merge(action: "cluster.get_settings", rest_api: "cluster.get_settings")
  response.body
end

#health(params = {}) ⇒ Object

Simple status on the health of the cluster. The API can also be executed against one or more indices to get just the specified indices health.

params - Parameters Hash

:index - a single index name or an Array of index names
:level - one of "cluster", "indices", or "shards"
:wait_for_status - one of "green", "yellow", or "red"
:wait_for_relocating_shards - a number controlling to how many relocating shards to wait for
:wait_for_nodes - the request waits until the specified number N of nodes is available
:timeout - how long to wait [default is "30s"]

See www.elastic.co/guide/en/elasticsearch/reference/current/cluster-health.html

Returns the response as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 36

def health( params = {} )
  response = client.get "/_cluster/health{/index}", params.merge(action: "cluster.health", rest_api: "cluster.health")
  response.body
end

#indices ⇒ Object

List all indices currently defined. This is just a convenience method around the ‘state` call that extracts and returns the indices section.

Returns the indices definitions as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 234

def indices
  state(metrics: "metadata").dig("metadata", "indices")
end

#nodes ⇒ Object

List all nodes currently part of the cluster. This is just a convenience method around the ‘state` call that extracts and returns the nodes section.

Returns the nodes definitions as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 243

def nodes
  state(metrics: "nodes").dig("nodes")
end

#pending_tasks(params = {}) ⇒ Object

Returns a list of any cluster-level changes (e.g. create index, update mapping, allocate or fail shard) which have not yet been executed.

params - Parameters Hash

See www.elastic.co/guide/en/elasticsearch/reference/current/cluster-pending.html

Returns the response as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 82

def pending_tasks( params = {} )
  response = client.get "/_cluster/pending_tasks", params.merge(action: "cluster.pending_tasks", rest_api: "cluster.pending_tasks")
  response.body
end

#pending_tasks? ⇒ Boolean

Returns ‘true` if there items in the pending task list. Returns `false` if the pending task list is empty. Returns `nil` if the response body does not contain the “tasks” field.

Returns:

  • (Boolean) 


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# File 'lib/elastomer/client/cluster.rb', line 90

def pending_tasks?
  hash = pending_tasks
  return nil unless hash.key? "tasks"
  hash["tasks"].length > 0
end

#reroute(commands, params = {}) ⇒ Object

Explicitly execute a cluster reroute allocation command. For example, a shard can be moved from one node to another explicitly, an allocation can be canceled, or an unassigned shard can be explicitly allocated on a specific node.

commands - A command Hash or an Array of command Hashes params - Parameters Hash

Examples

reroute(move: { index: 'test', shard: 0, from_node: 'node1', to_node: 'node2' })

reroute([
  { move:     { index: 'test', shard: 0, from_node: 'node1', to_node: 'node2' }},
  { allocate: { index: 'test', shard: 1, node: 'node3' }}
])

reroute(commands: [
  { move:     { index: 'test', shard: 0, from_node: 'node1', to_node: 'node2' }},
  { allocate: { index: 'test', shard: 1, node: 'node3' }}
])

See www.elastic.co/guide/en/elasticsearch/reference/current/cluster-reroute.html

Returns the response as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 149

def reroute( commands, params = {} )
  if commands.is_a?(Hash) && commands.key?(:commands)
    body = commands
  elsif commands.is_a?(Hash)
    # Array() on a Hash does not do what you think it does - that is why
    # we are explicitly wrapping the Hash via [commands] here.
    body = {commands: [commands]}
  else
    body = {commands: Array(commands)}
  end

  response = client.post "/_cluster/reroute", params.merge(body: body, action: "cluster.reroute", rest_api: "cluster.reroute")
  response.body
end

#state(params = {}) ⇒ Object

Comprehensive state information of the whole cluster. For 1.x metric and index filtering, use the :metrics and :indices parameter keys.

The list of available metrics are:

version, master_node, nodes, routing_table, metadata, blocks

params - Parameters Hash

:metrics - list of metrics to select as an Array
:indices - a single index name or an Array of index names

See www.elastic.co/guide/en/elasticsearch/reference/current/cluster-state.html

Returns the response as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 54

def state( params = {} )
  response = client.get "/_cluster/state{/metrics}{/indices}", params.merge(action: "cluster.state", rest_api: "cluster.state")
  response.body
end

#stats(params = {}) ⇒ Object

Retrieve statistics from a cluster wide perspective. The API returns basic index metrics (shard numbers, store size, memory usage) and information about the current nodes that form the cluster (number, roles, os, jvm versions, memory usage, cpu and installed plugins).

params - Parameters Hash

See www.elastic.co/guide/en/elasticsearch/reference/current/cluster-stats.html

Returns the response as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 69

def stats( params = {} )
  response = client.get "/_cluster/stats", params.merge(action: "cluster.stats", rest_api: "cluster.stats")
  response.body
end

#templates ⇒ Object

List all templates currently defined. This is just a convenience method around the ‘state` call that extracts and returns the templates section.

Returns the template definitions as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 226

def templates
  state(metrics: "metadata").dig("metadata", "templates")
end

#update_aliases(actions, params = {}) ⇒ Object

Perform an aliases action on the cluster. We are just a teensy bit clever here in that a single action can be given or an array of actions. This API method will wrap the request in the appropriate […] body construct.

actions - An action Hash or an Array of action Hashes params - Parameters Hash

Examples

update_aliases(add: { index: 'users-1', alias: 'users' })

update_aliases([
  { remove: { index: 'users-1', alias: 'users' }},
  { add:    { index: 'users-2', alias: 'users' }}
])

See www.elastic.co/guide/en/elasticsearch/reference/current/indices-aliases.html

Returns the response body as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 207

def update_aliases( actions, params = {} )
  if actions.is_a?(Hash) && actions.key?(:actions)
    body = actions
  elsif actions.is_a?(Hash)
    # Array() on a Hash does not do what you think it does - that is why
    # we are explicitly wrapping the Hash via [actions] here.
    body = {actions: [actions]}
  else
    body = {actions: Array(actions)}
  end

  response = client.post "/_aliases", params.merge(body: body, action: "cluster.update_aliases", rest_api: "indices.update_aliases")
  response.body
end

#update_settings(body, params = {}) ⇒ Object

Update cluster wide specific settings. Settings updated can either be persistent (applied cross restarts) or transient (will not survive a full cluster restart).

body - The new settings as a Hash or a JSON encoded String params - Parameters Hash

See www.elastic.co/guide/en/elasticsearch/reference/current/cluster-update-settings.html

Returns the response as a Hash



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# File 'lib/elastomer/client/cluster.rb', line 119

def update_settings( body, params = {} )
  response = client.put "/_cluster/settings", params.merge(body: body, action: "cluster.update_settings", rest_api: "cluster.put_settings")
  response.body
end