how to get the state of all shadows, classic and named ?

Question

I have a thing with a classic shadow and several named shadows. 
I don't  know the name of the named shadows. they are created by the devices with a uuid the moment the device connects to IoT Core
I need to get in a single document the current state of all the shadows of the thing. one json that includes the classic shadow current state together with the current state of all the named shadows

Is it possible to do this with  one single API call? using IoT core and/or other services like fleet indexing ?

Currently I'm using the API to fetch all the named shadows of the thing and then fetch each shadow document per named shadow. But maybe there is a better option.

thanks

Answer

Hi mvp, you are right, the only way to get the list of named shadows for a Thing is to call the [ListNamedShadowsForThing](https://docs.aws.amazon.com/iot/latest/developerguide/device-shadow-rest-api.html#API_ListNamedShadowsForThing) API and fetch the classic shadow and named shadow individually by calling [GetThingShadow](https://docs.aws.amazon.com/iot/latest/developerguide/device-shadow-rest-api.html#API_GetThingShadow)

Ideally the named shadow name should be known by your backend, do you have a special reason why you use a UUID as the named shadow name? If your backend could guess the name, you could avoid listing the shadow for each Thing and fetch the shadow directly.

Using predefined names for your named shadows also allows you to use AWS IoT [AWS IoT Fleet Indexing](https://docs.aws.amazon.com/iot/latest/developerguide/iot-indexing.html). To [enable Fleet Indexing on named Shadow](https://docs.aws.amazon.com/iot/latest/developerguide/managing-index.html) you need to specify the list of named shadow names. Once done, you can query the Index and retrieve multiple shadows at the same time using a Lucene based query syntax. In the example below I retrieve all Things and corresponding shadows documents that have a named shadow `Home01` and an attribute `welcome` in the `reported` section:

```
> aws iot search-index --query-string "shadow.name.Home01.reported.welcome: *"
{
    "things": [
        {
            "thingName": "ShadowTest01",
            "thingId": "2254b6c2-6f86-4d32-898b-9335a941882a",
            "shadow": "{\"name\":{\"Home01\":{\"desired\":{\"welcome\":\"aws-iot\"},\"reported\":{\"welcome\":\"aws-iot\"},\"metadata\":{\"desired\":{\"welcome\":\"aws-iot\"},\"reported\":{\"welcome\":\"aws-iot\"}},\"hasDelta\":false,\"version\":1}}}",
            "connectivity": {
                "connected": false
            }
        },
        {
            "thingName": "ShadowTest02",
            "thingId": "28295d73-7790-40dc-825f-16bfe7cef6a2",
            "shadow": "{\"name\":{\"Home01\":{\"reported\":{\"welcome\":\"Second device!\"},\"metadata\":{\"reported\":{\"welcome\":\"Second device!\"}},\"hasDelta\":false,\"version\":3}}}",
            "connectivity": {
                "connected": false
            }
        }
    ]
}
```

how to get the state of all shadows, classic and named ?

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