Get the value stored at the given JSONPath inside the given key, deserializing the value into the type T. You can use this to deserialize your custom JSON::Serializable objects.

struct Order
  include JSON::Serializable
  getter id : UUID
  getter customer_id : UUID
  getter line_items : Array(LineItem)
end

struct LineItem
  include JSON::Serializable
  getter product_id : UUID
  getter quantity : Int32
  getter unit_price_cents : Int32
end

# Get the Order at the root
redis.json.get("order:#{id}", ".", as: Order)
# Get the LineItems at the `.line_items` JSONPath
# Note the `$` at the beginning to make it an array
redis.json.get("order:#{id}", "$.line_items", as: Array(LineItem))
# Get only the `product_id` properties of all the `line_items`
redis.json.get("order:#{id}", "$.line_items..product_id", as: Array(UUID))

NOTE This method cannot be used in a pipeline or Redis::Connection#multi block because it operates on the value returned from the Redis server inside the method, which isn't possible when using pipelines or multi.

Get the raw JSON string representation at the given key nested at the given JSONPath.

email = redis.json.get("user:#{id}", ".email").as(String)
# => "[email protected]"

Get the values stored at the specifed JSONPaths, deserializing them into the specified type as values in a Hash.

if result = redis.json.get("posts:#{id}", %w[title tags], as: String | Array(String))
  result         # => {"title" => "JSON with Redis", tags: ["redis", "json", "crystal"]}
  typeof(result) # => Hash(String, String | Array(String))
end

NOTE This method cannot be used in a pipeline or Redis::Connection#multi block because it operates on the value returned from the Redis server, which isn't a thing when using pipelines or multi.

Get the raw JSON string at the specified key

Get the values for all keys at the specified JSONPaths.

NOTE This method cannot be used in a pipeline or Redis::Connection#multi block because it operates on the value returned from the Redis server inside the method, which isn't possible when using pipelines or multi.

NOTE If you are using a cluster, the keys must all be on the same shard, or you may only get some of them back with this method. When using #mget in a cluster, you'll most likely want to use subhashed keys (with {} around the same part of the name) to ensure all keys are on the same shard.

Increment the number at the specified JSONPath

redis.json.numincrby "product:#{id}", ".purchase_count", 1, as: Int64
# => 2

If key exists and an incrementable number exists at the specified JSONPath (including the possibility of incrementing multiple numbers if the JSONPath resolves to multiple numeric values), then this method returns a value of type T. If the JSONPath resolves to multiple values (for example, it begins with "$" or is recursive), you will need to specify that it can be an Array of that type.

Increment the number at the specified JSONPath

redis.json.numincrby "product:#{id}", ".purchase_count", 1

Set the given key to the given JSON value. The value will have to_json called on it automatically. The nx and xx arguments are identical to Redis::Commands#set.

Store a user at the root JSONPath (.) of the specified key:

struct User
  include JSON::Serializable

  getter id : UUID
  getter name : String
  getter email : String
end

redis.json.set "user:#{user.id}", ".", user

Update (with xx so we ensure the key exists) a user's email by setting the new email value at the .email JSONPath:

redis.json.set "user:#{id}", ".email", new_email, xx: true