Class: Google::Cloud::PubSub::Snapshot

Inherits:
Object
  • Object
show all
Defined in:
lib/google/cloud/pubsub/snapshot.rb,
lib/google/cloud/pubsub/snapshot/list.rb

Overview

Snapshot

A named resource created from a subscription to retain a stream of messages from a topic. A snapshot is guaranteed to retain:

  • The existing backlog on the subscription. More precisely, this is defined as the messages in the subscription's backlog that are unacknowledged upon the successful completion of the create_snapshot operation; as well as:
  • Any messages published to the subscription's topic following the successful completion of the create_snapshot operation.

Examples:

require "google/cloud/pubsub"

pubsub = Google::Cloud::PubSub.new
sub = pubsub.subscription "my-sub"

snapshot = sub.create_snapshot "my-snapshot"
snapshot.name #=> "projects/my-project/snapshots/my-snapshot"

Defined Under Namespace

Classes: List

Instance Method Summary collapse

Instance Method Details

#delete ⇒ Boolean

Removes an existing snapshot. All messages retained in the snapshot are immediately dropped. After a snapshot is deleted, a new one may be created with the same name, but the new one has no association with the old snapshot or its subscription, unless the same subscription is specified.

Examples:

require "google/cloud/pubsub"

pubsub = Google::Cloud::PubSub.new

pubsub.snapshots.each do |snapshot|
  snapshot.delete
end

Returns:

  • (Boolean) —

    Returns true if the snapshot was deleted.



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# File 'lib/google/cloud/pubsub/snapshot.rb', line 166

def delete
  ensure_service!
  service.delete_snapshot name
  true
end

#expiration_time ⇒ Time

The snapshot is guaranteed to exist up until this time. A newly-created snapshot expires no later than 7 days from the time of its creation. Its exact lifetime is determined at creation by the existing backlog in the source subscription. Specifically, the lifetime of the snapshot is 7 days - (age of oldest unacked message in the subscription). For example, consider a subscription whose oldest unacked message is 3 days old. If a snapshot is created from this subscription, the snapshot -- which will always capture this 3-day-old backlog as long as the snapshot exists -- will expire in 4 days.

Examples:

require "google/cloud/pubsub"

pubsub = Google::Cloud::PubSub.new
sub = pubsub.subscription "my-sub"

snapshot = sub.create_snapshot "my-snapshot"
snapshot.topic.name #=> "projects/my-project/topics/my-topic"
snapshot.expiration_time

Returns:

  • (Time) —

    The time until which the snapshot is guaranteed to exist.



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# File 'lib/google/cloud/pubsub/snapshot.rb', line 109

def expiration_time
  self.class.timestamp_from_grpc @grpc.expire_time
end

#labels ⇒ Hash

A hash of user-provided labels associated with this snapshot. Labels can be used to organize and group snapshots.See Creating and Managing Labels.

The returned hash is frozen and changes are not allowed. Use #labels= to update the labels for this snapshot.

Returns:

  • (Hash) —

    The frozen labels hash.



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# File 'lib/google/cloud/pubsub/snapshot.rb', line 123

def labels
  @grpc.labels.to_h.freeze
end

#labels=(new_labels) ⇒ Object

Sets the hash of user-provided labels associated with this snapshot. Labels can be used to organize and group snapshots. Label keys and values can be no longer than 63 characters, can only contain lowercase letters, numeric characters, underscores and dashes. International characters are allowed. Label values are optional. Label keys must start with a letter and each label in the list must have a different key. See Creating and Managing Labels.

Parameters:

  • new_labels (Hash) —

    The new labels hash.

Raises:

  • (ArgumentError) 


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# File 'lib/google/cloud/pubsub/snapshot.rb', line 139

def labels= new_labels
  raise ArgumentError, "Value must be a Hash" if new_labels.nil?
  labels_map = Google::Protobuf::Map.new :string, :string
  Hash(new_labels).each { |k, v| labels_map[String(k)] = String(v) }
  update_grpc = @grpc.dup
  update_grpc.labels = labels_map
  @grpc = service.update_snapshot update_grpc, :labels
end

#name ⇒ Object

The name of the snapshot. Format is projects/{project}/snapshots/{snap}.



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# File 'lib/google/cloud/pubsub/snapshot.rb', line 63

def name
  @grpc.name
end

#topic ⇒ Topic

The Topic from which this snapshot is retaining messages.

Examples:

require "google/cloud/pubsub"

pubsub = Google::Cloud::PubSub.new
sub = pubsub.subscription "my-sub"

snapshot = sub.create_snapshot "my-snapshot"
snapshot.topic.name #=> "projects/my-project/topics/my-topic"

Returns:



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# File 'lib/google/cloud/pubsub/snapshot.rb', line 81

def topic
  Topic.from_name @grpc.topic, service
end