Solid Cable

After installation, you must define the cable database configuration in config/database.yml. The name used in config/database.yml must match the name used in the connects_to block of config/cable.yml (which defaults to cable).

SQLite Example:

production:
  primary:
    <<: *default
    database: storage/production.sqlite3
  cable:
    <<: *default
    database: storage/production_cable.sqlite3
    migrations_paths: db/cable_migrate

MySQL/PostgreSQL/Trilogy Example:

production:
  primary: &primary_production
    <<: *default
    database: app_production
    username: app
    password: <%= ENV["APP_DATABASE_PASSWORD"] %>
  cable:
    <<: *primary_production
    database: app_production_cable
    migrations_paths: db/cable_migrate

After configuring the database, run bin/rails db:prepare in production to create the database and load the schema.

Solid Cable can encrypt stored message payloads using Active Record Encryption.

Requirements:

1. Your application must be configured to use Active Record Encryption.
2. You must include the msgpack gem (Solid Cable uses the binary MessagePack serializer by default).
3. Note for PostgreSQL users: Active Record Encryption does not support encrypted binary columns on PostgreSQL with Rails 7. Solid Cable will raise an error during boot if this combination is used.

Step 1: Update config/cable.yml

production:
  adapter: solid_cable
  encrypt: true
  connects_to:
    database:
      writing: cable

Step 2: Configure encryption context in an initializer Since encryption context properties contain Ruby objects, they must be set in config/initializers/solid_cable.rb rather than the YAML config:

SolidCable.configuration.encryption_context_properties = {
  encryptor: ActiveRecord::Encryption::Encryptor.new,
  message_serializer: ActiveRecord::Encryption::MessageSerializer.new
}

# config/initializers/solid_cable.rb
SolidCable.configuration.encryption_context_properties = {
  encryptor: ActiveRecord::Encryption::Encryptor.new,
  message_serializer: ActiveRecord::Encryption::MessageSerializer.new
}

All Solid Cable settings are managed in config/cable.yml.

Default Configuration:

production:
  adapter: solid_cable
  connects_to:
    database:
      writing: cable
  polling_interval: 0.1.seconds
  message_retention: 1.day

Available Options:

• connects_to: Sets the Active Record database configuration for Solid Cable models. Supports all Active Record options.
• polling_interval: Frequency of the polling interval. (Default: 0.1.seconds)
• message_retention: Retention time for messages. Used as the cut-off for trimming. (Default: 1.day)
• autotrim: Whether Solid Cable handles autotrimming. (Default: true)
• silence_polling: Whether to silence Active Record logs emitted during polling. (Default: true)
• use_skip_locked: Whether to use FOR UPDATE SKIP LOCKED during trimming. Set to false if your database doesn't support it (e.g., MySQL < 8 or PostgreSQL < 9.5). (Default: true)
• trim_batch_size: Batch size for deleting old records. (Default: 100)
• reconnect_attempts: Number of connection attempts or an array of durations to wait between attempts. (Default: 1 retry attempt)
• encrypt: Whether to encrypt message payloads with Active Record Encryption. (Default: false)

Solid Cable is configured via a configuration object, typically initialized in config/initializers/solid_cable.rb. You can tune performance, retention, and database behavior using several configuration keys.

Database and Polling

• connects_to: A hash of database connection configurations.
• silence_polling: Boolean. When false, polling is disabled. Defaults to true.
• polling_interval: The duration between polls. Defaults to 0.1.seconds.
• use_skip_locked: Boolean. Enables SKIP LOCKED for database queries to improve concurrency. Defaults to true.

Message Retention and Trimming

• message_retention: The duration for which messages are kept. Defaults to 1.day.
• autotrim: Boolean. Enables automatic trimming of old messages. Defaults to true.
• trim_batch_size: The number of records to delete in a single trim operation. Defaults to 100 if set to less than 2.

Writer and Reconnection

• writer_batch_size: Number of messages to batch during writes. Defaults to 4.
• writer_batch_delay: The delay applied to writer batches. Defaults to 0.001.seconds.
• reconnect_attempts: An integer representing the number of attempts, or an array of specific delays. Defaults to 1 (represented as [0]).

Encryption

• encrypt: Enables message encryption. Set this to a truthy value to enable.
• encryption_context_properties: A hash of properties for the encryption context. If encrypt is enabled, it defaults to using ActiveRecord::Encryption::Encryptor (with compression) and ActiveRecord::Encryption::MessagePackMessageSerializer (a binary-only serializer that is 40% more efficient than the default).

# Example configuration in config/initializers/solid_cable.rb
SolidCable.configure do |config|
  config.connects_to = { database: :cable }
  config.polling_interval = 0.5.seconds
  config.message_retention = 1.week
  config.encrypt = true
  config.encryption_context_properties = { some_key: 'some_value' }
end