[cache.try-get]

cache.try-get is a slot in the cache namespace, in Hyperlambda, the language of Magic Cloud. Returns a cached value by key if it exists, or creates a new cached item and returning it.

• Value (cache-key), required: Cache key to retrieve
• Returns: Resolves to the cached value, or the newly created value when the key is missing

Arguments

Required arguments come first, then the optional ones in the order they are declared.

Argument	Type	Required	Description
[.lambda]	lambda	yes	Callback executed to create the cached value when the key is missing.
[expiration]	long	no	Expiration in seconds for newly created value. Default: 5.

Guide: How to use [cache.try-get]

JSON declaration

This is the complete declaration of cache.try-get, as the running system describes it. It is also published as slot.json.

JSON declaration

{
  "name": "cache.try-get",
  "description": "Returns a cached value by key if it exists, or creates a new cached item and returning it",
  "signature": {
    "input": {
      "kind": "cache-key",
      "description": "Cache key to retrieve",
      "required": true,
      "mode": "ValueOrExpression"
    },
    "children": {
      "expiration": {
        "type": "long",
        "kind": "duration-seconds",
        "description": "Expiration in seconds for newly created value",
        "required": false,
        "mode": "ValueOrExpression",
        "cardinality": "ZeroOrOne",
        "default": "5",
        "role": "Option",
        "projection": "Value"
      },
      ".lambda": {
        "type": "lambda",
        "description": "Callback executed to create the cached value when the key is missing",
        "required": true,
        "mode": "ExecutableLambda",
        "cardinality": "ExactlyOne",
        "role": "Callback",
        "evaluation": "EvalBlock",
        "projection": "Value"
      }
    },
    "output": {
      "mode": "Value",
      "kind": "cache-value,text",
      "description": "Resolves to the cached value, or the newly created value when the key is missing"
    }
  }
}

---

← cache.set

all cache.* slots