Class: ConvertSdk::Stores::RedisStore

Inherits:
Object
  • Object
show all
Defined in:
lib/convert_sdk/stores/redis_store.rb

Overview

A first-party, in-tree store adapter backed by Redis — the cross-process answer to MemoryStore's per-process limitation.

== Why Redis (FR49)

MemoryStore keeps state in a single process. Puma clusters, Sidekiq worker fleets, and Lambda invocations each run in separate processes, so sticky bucketing (Story 2.11) and goal deduplication (Story 4.3) that round-trip through a +MemoryStore+ are inconsistent across the fleet. +RedisStore+ shares that state through a Redis instance, giving every process the same view.

== Zero gemspec footprint

The +redis+ gem is the user's dependency, never the SDK's: it is NOT a gemspec runtime dependency and is +require+-d lazily inside #initialize — and only when a client is built from connection options. Requiring this file (which +lib/convert_sdk.rb+ does unconditionally) therefore never pulls in +redis+, so +require "convert_sdk"+ stays green for users who do not install it. If a caller asks +RedisStore+ to build its own client without +redis+ installed, instantiation raises an actionable error naming the gem to add — a wiring-time programmer error, sanctioned in the same class as +ConvertSdk.create+'s argument validation, NOT a business path.

== Construction

# Preferred: inject an existing client (connection reuse / pooling). # No require "redis", no Redis.new — works even where the adapter # file is loaded without the gem present. store = ConvertSdk::Stores::RedisStore.new(redis: Redis.new(url: ...))

# Or pass connection options; the adapter lazily requires redis and # constructs the client itself. store = ConvertSdk::Stores::RedisStore.new(url: "redis://localhost:6379/0")

An optional +key_prefix+ namespaces every key (default +"convert:"+) so the SDK's keys do not collide with other tenants of the same Redis database.

== Thin adapter — resilience lives upstream

This adapter is serialization + connection only. It does NOT rescue Redis client exceptions: DataStoreManager (Story 2.1) already wraps every +get+/+set+ in a rescue-log passthrough, degrading a raising store to +nil+/no-op instead of crashing the host. Duplicating that rescue here would swallow errors the manager is responsible for logging.

== Cross-process consistency caveat

Visitor-data merges are a read-modify-write. In-process that sequence is atomic under DataStoreManager's mutex, but across processes sharing one Redis there is no such lock: concurrent writers race and the last write wins. This matches the JS SDK contract. The SDK does NOT use Lua scripts or +WATCH+/+MULTI+ to close that race — that is deliberately out of scope.

Sidekiq / Lambda deployment guidance: see the Epic 5 documentation.

Constant Summary collapse

DEFAULT_KEY_PREFIX =

Default namespace prepended to every key written to Redis.

"convert:"

Instance Method Summary collapse

Constructor Details

#initialize(redis: nil, key_prefix: DEFAULT_KEY_PREFIX, **options) ⇒ RedisStore

Returns a new instance of RedisStore.

Parameters:

  • redis (Object, nil) (defaults to: nil) —

    an existing redis-rb-compatible client responding to +#get+/+#set+. When supplied, +redis+ is NOT required and no new client is constructed (preferred — enables connection reuse).

  • key_prefix (String) (defaults to: DEFAULT_KEY_PREFIX) —

    namespace prepended to every key (default +"convert:"+).

  • options (Hash) —

    connection options (e.g. +url:+) forwarded to +Redis.new+ when no +redis:+ client is injected. Triggers the lazy +require "redis"+.

Raises:

  • (LoadError) —

    re-raised as an actionable error when +redis:+ is omitted and the +redis+ gem is not installed.



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# File 'lib/convert_sdk/stores/redis_store.rb', line 76

def initialize(redis: nil, key_prefix: DEFAULT_KEY_PREFIX, **options)
  @key_prefix = key_prefix
  @client = redis || build_client(options)
end

Instance Method Details

#get(key) ⇒ Object?

Read and deserialize the value stored under +key+.

Parameters:

  • key (String) —

    the (unprefixed) lookup key.

Returns:

  • (Object, nil) —

    the JSON-parsed value (string-keyed hashes, numbers, arrays, booleans), or +nil+ when the key is absent.



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# File 'lib/convert_sdk/stores/redis_store.rb', line 86

def get(key)
  raw = @client.get(namespaced(key))
  raw.nil? ? nil : JSON.parse(raw)
end

#set(key, value) ⇒ Object

Serialize +value+ to JSON and store it under +key+, overwriting any existing value.

Parameters:

  • key (String) —

    the (unprefixed) storage key.

  • value (Object) —

    a JSON-serializable value (StoreData shape).

Returns:

  • (Object) —

    the client's +set+ return value.



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# File 'lib/convert_sdk/stores/redis_store.rb', line 97

def set(key, value)
  @client.set(namespaced(key), JSON.generate(value))
end