module Google::Cloud::PubSub
Google
Cloud
Pub/Sub is designed to provide reliable, many-to-many, asynchronous messaging between applications. Publisher applications can send messages to a “topic” and other applications can subscribe to that topic to receive the messages. By decoupling senders and receivers, Google
Cloud
Pub/Sub allows developers to communicate between independently written applications.
Constants
- VERSION
Public Class Methods
Configure the Google
Cloud
PubSub
library.
The following PubSub
configuration parameters are supported:
-
`project_id` - (String) Identifier for a
PubSub
project. (The parameter `project` is considered deprecated, but may also be used.) -
`credentials` - (String, Hash, Google::Auth::Credentials) The path to the keyfile as a String, the contents of the keyfile as a Hash, or a Google::Auth::Credentials object. (See {PubSub::Credentials}) (The parameter `keyfile` is considered deprecated, but may also be used.)
-
`scope` - (String, Array<String>) The OAuth 2.0 scopes controlling the set of resources and operations that the connection can access.
-
`retries` - (Integer) Number of times to retry requests on server error.
-
`timeout` - (Integer) Default timeout to use in requests.
-
`endpoint` - (String) Override of the endpoint host name, or `nil` to use the default endpoint.
-
`emulator_host` - (String) Host name of the emulator. Defaults to `ENV`
-
`on_error` - (Proc) A Proc to be run when an error is encountered on a background thread. The Proc must take the error object as the single argument. (See {Subscriber.on_error}.)
@return [Google::Cloud::Config] The configuration object the
Google::Cloud::PubSub library uses.
# File lib/google/cloud/pubsub.rb, line 138 def self.configure yield Google::Cloud.configure.pubsub if block_given? Google::Cloud.configure.pubsub end
@private Default credentials.
# File lib/google/cloud/pubsub.rb, line 154 def self.default_credentials scope: nil Google::Cloud.configure.pubsub.credentials || Google::Cloud.configure.credentials || PubSub::Credentials.default(scope: scope) end
@private Default project.
# File lib/google/cloud/pubsub.rb, line 146 def self.default_project_id Google::Cloud.configure.pubsub.project_id || Google::Cloud.configure.project_id || Google::Cloud.env.project_id end
Creates a new object for connecting to the Pub/Sub service. Each call creates a new connection.
For more information on connecting to Google
Cloud
see the {file:AUTHENTICATION.md Authentication Guide}.
@param [String] project_id Project
identifier for the Pub/Sub service
you are connecting to. If not present, the default project for the credentials is used.
@param [String, Hash, Google::Auth::Credentials] credentials The path to
the keyfile as a String, the contents of the keyfile as a Hash, or a Google::Auth::Credentials object. (See {PubSub::Credentials})
@param [String, Array<String>] scope The OAuth 2.0 scopes controlling
the set of resources and operations that the connection can access. See [Using OAuth 2.0 to Access Google APIs](https://developers.google.com/identity/protocols/OAuth2). The default scope is: * `https://www.googleapis.com/auth/pubsub`
@param [Integer] timeout Default timeout to use in requests. Optional. @param [String] endpoint Override of the endpoint host name. Optional.
If the param is nil, uses the default endpoint.
@param [String] emulator_host Pub/Sub emulator host. Optional.
If the param is nil, uses the value of the `emulator_host` config.
@param [String] project Alias for the `project_id` argument. Deprecated. @param [String] keyfile Alias for the `credentials` argument.
Deprecated.
@return [Google::Cloud::PubSub::Project]
@example
require "google/cloud/pubsub" pubsub = Google::Cloud::PubSub.new topic = pubsub.topic "my-topic" topic.publish "task completed"
# File lib/google/cloud/pubsub.rb, line 76 def self.new project_id: nil, credentials: nil, scope: nil, timeout: nil, endpoint: nil, emulator_host: nil, project: nil, keyfile: nil project_id ||= (project || default_project_id) scope ||= configure.scope timeout ||= configure.timeout endpoint ||= configure.endpoint emulator_host ||= configure.emulator_host if emulator_host project_id = project_id.to_s # Always cast to a string raise ArgumentError, "project_id is missing" if project_id.empty? service = PubSub::Service.new project_id, :this_channel_is_insecure, host: emulator_host, timeout: timeout return PubSub::Project.new service end credentials ||= (keyfile || default_credentials(scope: scope)) unless credentials.is_a? Google::Auth::Credentials credentials = PubSub::Credentials.new credentials, scope: scope end project_id ||= credentials.project_id if credentials.respond_to? :project_id project_id = project_id.to_s # Always cast to a string raise ArgumentError, "project_id is missing" if project_id.empty? service = PubSub::Service.new project_id, credentials, host: endpoint, timeout: timeout PubSub::Project.new service end