# List all features of a specific thing

`GET /api/2/things/{thingId}/features`

Returns all features of the thing identified by the `thingId` path parameter.

Authentication (security requirement alternatives):

```json
[
  {
    "OpenIDConnect": []
  },
  {
    "NginxBasic": []
  },
  {
    "Bearer": []
  }
]
```

- OpenIDConnect: openIdConnect. OpenID Connect Discovery URL. The placeholder is replaced by Swagger UI when configured.
- NginxBasic: http (basic). Eclipse Ditto sandbox demo user (demo1 ... demo9) + password (demo)
- Bearer: http (bearer). A JSON Web Token issued by a supported OAuth 2.0 Identity Provider.

Parameters:

- `thingId` (path, string, required) - The ID of a thing needs to follow the namespaced entity ID notation (see [Ditto documentation on namespaced entity IDs](https://www.eclipse.dev/ditto/basic-namespaces-and-names.html#namespaced-id)).
  Type: string

- `fields` (query, string, optional) - Contains a comma-separated list of fields from one or more features to be
included in the returned JSON.

#### Selectable fields

* `{featureId}` The ID of the feature to select properties in
  * `properties`
    Supports selecting arbitrary sub-fields by using a comma-separated list:
      * several properties paths can be passed as a comma-separated list of JSON pointers (RFC-6901)
        For example:
          * `?fields={featureId}/properties/color` would select only `color` property value (if present) of the feature identified with `{featureId}`
          * `?fields={featureId}/properties/color,properties/brightness` would select only `color` and `brightness` property values (if present) of the feature identified with `{featureId}`
    Supports selecting arbitrary sub-fields of objects by wrapping sub-fields inside parentheses `( )`:
      * a comma-separated list of sub-fields (a sub-field is a JSON pointer (RFC-6901) separated with `/`) to select
      * sub-selectors can be used to request only specific sub-fields by placing expressions in parentheses `( )` after a selected subfield
        For example:
         * `?fields={featureId}/properties(color,brightness)` would select only `color` and `brightness` property values (if present) of the feature identified with `{featureId}`
         * `?fields={featureId}/properties(location/longitude)` would select the `longitude` value inside the `location` object of the feature identified with `{featureId}`


#### Examples
* `?fields=EnvironmentScanner/properties(temperature,humidity)`
* `?fields=EnvironmentScanner/properties(temperature,humidity),Vehicle/properties/configuration`
  Type: string

- `If-Match` (header, string, optional) - The `If-Match` header which has to conform to RFC-7232 (Conditional Requests). Common usages are:
  * optimistic locking by specifying the `ETag` from a previous HTTP response, e.g. `If-Match: "hash:a75ece4e"`
  * retrieving or modifying a resource only if it already exists, e.g. `If-Match: *`
  Type: string

- `If-None-Match` (header, string, optional) - The `If-None-Match` header, which has to conform to RFC-7232 (Conditional Requests). A common usage scenario is to modify a resource only if it does not yet exist, thus to create it, by specifying `If-None-Match: *`.
  Type: string

- `requested-acks` (query, string, optional) - Contains the "requested acknowledgements" for this modifying request as comma separated list. The HTTP call will
block until all requested acknowledgements were aggregated or will time out based on the specified `timeout`
parameter.

The default (if omitted) requested acks is `requested-acks=twin-persisted` which will block the
HTTP call until the change was persited to the twin.
  Type: string

- `timeout` (query, string, optional) - Defines how long the backend should wait for completion of the request, e.g. applied when waiting for requested
acknowledgements via the `requested-acks` param. Can be specified without unit (then seconds are assumed) or
together with `s`, `ms` or `m` unit. Example: `42s`, `1m`.

The default (if omitted) and maximum timeout is `60s`. A value of `0` applies fire and forget semantics for
the command resulting in setting `response-required=false`.
  Type: string

- `response-required` (query, boolean, optional) - Defines whether a response is required to the API call or not - if set to `false` the response will directly
sent back with a status code of `202` (Accepted).

The default (if ommited) response is `true`.
  Type: boolean

- `condition` (query, string, optional) - Defines that the request should only be processed if the given condition is met. The condition can be specified using RQL syntax. 
#### Examples
E.g. if the temperature is not 23.9 update it to 23.9:
* ```PUT /api/2/things/{thingId}/features/temperature/properties/value?condition=ne(features/temperature/properties/value,23.9)```

   `body: 23.9`

Further example conditions:
* ```?condition=eq(features/temperature/properties/unit,"Celsius")```
* ```?condition=ge(features/temperature/properties/lastModified,"2021-08-22T19:45:00Z")```
* ```?condition=gt(_modified,"2021-08-05T12:17:00Z")```
* ```?condition=exists(features/temperature/properties/value)```
* ```?condition=empty(features/temperature/properties/value)```
* ```?condition=and(gt(features/temperature/properties/value,18.5),lt(features/temperature/properties/value,25.2))```
* ```?condition=or(gt(features/temperature/properties/value,18.5),not(exists(features/temperature/properties/value))```
  Type: string

- `channel` (query, string, optional) - Defines to which channel to route the command: `twin` (digital twin) or `live` (the device).
* If setting the channel parameter is omitted, the `twin` channel is set by default and the command is routed to the persisted representation of a thing in Eclipse Ditto.
* When using the `live` channel, the command/message is sent towards the device.
  Type: string
  
  enum: ["twin","live"]

- `live-channel-condition` (query, string, optional) - Defines that the request should fetch thing data via `live` channel if the given condition is met. The condition can be specified using RQL syntax.
#### Examples

  * ```?live-channel-condition=lt(_modified,"2021-12-24T12:23:42Z")```

  * ```?live-channel-condition=ge(features/ConnectionStatus/properties/status/readyUntil,time:now)```
  Type: string

- `live-channel-timeout-strategy` (query, any, optional) - Defines a strategy how to handle timeouts of a live response to a request sent via `channel=live` or with a matching  live-channel-condition.
  Type: any
  
  enum: ["fail","use-twin"]

Responses:

- 200: The list of features of the specific thing were successfully
retrieved.

Content type: application/json

Type: Features

List of features where the key represents the `featureId` of each feature.
The `featureId` key must be unique in the list.

Schema: [Features](https://sourcey-ditto.pages.dev/http-api-doc/models/features.md)

Additional properties: 
  Reference: [Feature](https://sourcey-ditto.pages.dev/http-api-doc/models/feature.md); Type: Feature

```json
{
  "featureId1": {
    "definition": [
      "namespace:definition1:v1.0"
    ],
    "properties": {
      "property1": "value1"
    }
  },
  "featureId2": {
    "definition": [
      "namespace:definition2:v1.0"
    ],
    "properties": {
      "property2": "value2"
    }
  }
}
```

- 304: The (sub-)resource has not been modified. This happens when you specified a If-None-Match header which
 matches the current ETag of the (sub-)resource.

- 400: The request could not be completed. Possible reasons:
  * the `thingId` does not conform to the namespaced entity ID notation (see [Ditto documentation on namespaced entity IDs](https://www.eclipse.dev/ditto/basic-namespaces-and-names.html#namespaced-id)).
  * at least one of the defined query parameters is invalid.

Content type: application/json

Type: AdvancedError

Schema: [AdvancedError](https://sourcey-ditto.pages.dev/http-api-doc/models/advancederror.md)

- `status` (required)
  Type: integer
  
  The HTTP status of the error

- `error` (required)
  Type: string
  
  The error code of the occurred exception

- `message` (required)
  Type: string
  
  The message of the error - what went wrong

- `description` (optional)
  Type: string
  
  A description how to fix the error or more details

- `href` (optional)
  Type: string
  
  A link to further information about the error and how to fix it

- 401: The request could not be completed due to missing authentication.

Content type: application/json

Type: AdvancedError

Schema: [AdvancedError](https://sourcey-ditto.pages.dev/http-api-doc/models/advancederror.md)

- `status` (required)
  Type: integer
  
  The HTTP status of the error

- `error` (required)
  Type: string
  
  The error code of the occurred exception

- `message` (required)
  Type: string
  
  The message of the error - what went wrong

- `description` (optional)
  Type: string
  
  A description how to fix the error or more details

- `href` (optional)
  Type: string
  
  A link to further information about the error and how to fix it

- 404: The request could not be completed. The thing with the given ID was
not found or the features have not been defined.

Content type: application/json

Type: AdvancedError

Schema: [AdvancedError](https://sourcey-ditto.pages.dev/http-api-doc/models/advancederror.md)

- `status` (required)
  Type: integer
  
  The HTTP status of the error

- `error` (required)
  Type: string
  
  The error code of the occurred exception

- `message` (required)
  Type: string
  
  The message of the error - what went wrong

- `description` (optional)
  Type: string
  
  A description how to fix the error or more details

- `href` (optional)
  Type: string
  
  A link to further information about the error and how to fix it

- 412: A precondition for reading or writing the (sub-)resource failed. This will happen for write requests, if you
specified an If-Match or If-None-Match header, which fails the precondition check against the current ETag of
the (sub-)resource. For read requests, this error may only happen for a failing If-Match header. In case of a
failing If-None-Match header for a read request, status 304 will be returned instead.

Content type: application/json

Type: AdvancedError

Schema: [AdvancedError](https://sourcey-ditto.pages.dev/http-api-doc/models/advancederror.md)

- `status` (required)
  Type: integer
  
  The HTTP status of the error

- `error` (required)
  Type: string
  
  The error code of the occurred exception

- `message` (required)
  Type: string
  
  The message of the error - what went wrong

- `description` (optional)
  Type: string
  
  A description how to fix the error or more details

- `href` (optional)
  Type: string
  
  A link to further information about the error and how to fix it

## Examples

### cURL

```bash
curl -X GET 'https://ditto.eclipseprojects.io/api/2/things/string/features' \
  -H 'Authorization: Bearer YOUR_TOKEN'
```

### JavaScript

```javascript
const response = await fetch('https://ditto.eclipseprojects.io/api/2/things/string/features', {
  method: 'GET',
  headers: {
    'Authorization': 'Bearer YOUR_TOKEN',
  },
});

const data = await response.text();
```

### Python

```python
import requests

response = requests.get(
    'https://ditto.eclipseprojects.io/api/2/things/string/features',
    headers={
        'Authorization': 'Bearer YOUR_TOKEN',
    },
)
print(response.text)
```