ADD NGSI attribute custom node

.gitignore

@@ -9,3 +9,4 @@ images/
 *.png
 *.gif
 *.bmp
+yarn.lock

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## node-red-contrib-letsfiware-NGSI v0.7.1-next
 
+-  ADD NGSI attribute custom node (#60)
 -  ADD NGSI attributes custom node (#58)
 -  FIX node name (#56)
 -  ADD NGSI attribute value custom node (#55)

README.md

@@ -21,6 +21,7 @@ Node-RED implementation for FIWARE Open APIs
 -   [NGSI Entity CRUD](docs/custom_nodes/ngsi_entity_crud.md)
 -   [NGSI Source](docs/custom_nodes/ngsi_source.md)
 -   [NGSI Attributes](docs/custom_nodes/ngsi_attributes.md)
+-   [NGSI Attribute](docs/custom_nodes/ngsi_attribute.md)
 -   [NGSI Attribute value](docs/custom_nodes/ngsi_attribute_value.md)
 -   [NGSI Batch update](docs/custom_nodes/ngsi_batch_update.md)
 -   [NGSI Subscription](docs/custom_nodes/ngsi_subscription.md)

docs/custom_nodes/ngsi_attribute.md

@@ -0,0 +1,251 @@
+# NGSI attribute
+
+This custom node is a simple node that allows to read, update or delete an attribute in NGSIv2 entity.
+
+![](https://raw.githubusercontent.com/lets-fiware/node-red-contrib-letsfiware-NGSI/gh-pages/images/attribute-01.png)
+
+## Read an attribute
+
+It alows to read an attribute in NGSIv2 entity.
+
+### Properties
+
+![](https://raw.githubusercontent.com/lets-fiware/node-red-contrib-letsfiware-NGSI/gh-pages/images/attribute-02.png)
+
+-   `name`: A name for a node instance
+-   `Context Broker`: An endpoint of a context broker
+-   `ServicePath`: FIWARE Service Path
+-   `Action type`: read
+-   `Entity id`: Entity id to read an attribute
+-   `Entity type`: Entity type to read an attribute
+-   `Attribute name`: Name of attribute name to read 
+-   `Metadata`: List of metadata names
+-   `Skip forwarding`: If true, Context Broker skips forwarding to Context Providers
+
+### Exmaple
+
+#### Input
+
+Payload *JSON Object*
+
+A `msg.payload` should contain information related to the attribute to be read.
+
+```
+{}
+```
+
+```
+{
+  "attrName": "relativeHumidity"
+}
+```
+
+```
+{
+  "id": "E",
+  "type": "T",
+  "attrName": "relativeHumidity"
+}
+```
+
+#### Output
+
+Payload *JSON Object*
+
+A `msg.payload` contains an object representing the attribute.
+
+```
+{
+  "type":"Number",
+  "value":45,
+  "metadata":{}
+}
+```
+
+## Update an attribute
+
+It alows to update an attributes in NGSIv2 entity.
+
+### Properties
+
+![](https://raw.githubusercontent.com/lets-fiware/node-red-contrib-letsfiware-NGSI/gh-pages/images/attribute-03.png)
+
+-   `name`: A name for a node instance
+-   `Context Broker`: An endpoint of a context broker
+-   `ServicePath`: FIWARE Service Path
+-   `Action type`: update 
+-   `Entity id`: Entity id to update an attributes
+-   `Entity type`: Entity type to update an attributes
+-   `Attribute name`: Name of attribute name to update
+-   `Override metadata`: If true, replace the existing metadata
+-   `Forced update`: If true, it triggers matching subscriptions
+-   `Flow control`: If true, it enables flow control mechanism
+
+### Exmaple
+
+#### Input
+
+Payload  *JSON Object*
+
+A `msg.payload` should contain an object representing the attribute to be updated.
+
+```
+{
+  "type": "Number",
+  "value": 1234.5
+}
+```
+
+#### Output
+
+Payload *null or number*
+
+A `msg.payload` contains a status code.
+
+```
+204
+```
+
+```
+null
+```
+
+## Delete an attribute
+
+It alows to delete an attribute in NGSIv2 entity.
+
+### Properties
+
+![](https://raw.githubusercontent.com/lets-fiware/node-red-contrib-letsfiware-NGSI/gh-pages/images/attribute-04.png)
+
+-   `name`: A name for a node instance
+-   `Context Broker`: An endpoint of a context broker
+-   `ServicePath`: FIWARE Service Path
+-   `Action type`: upsert
+-   `Entity id`: Entity id to delete an attributes
+-   `Entity type`: Entity type to delete an attributes
+-   `Attribute name`: Name of attribute name to delete
+
+### Exmaple
+
+#### Input
+
+Payload  *JSON Object*
+
+A `msg.payload` should contain information related to the attribute to be deleted.
+
+```
+{}
+```
+
+```
+{
+  "attrName": "relativeHumidity"
+}
+```
+
+```
+{
+  "id": "E",
+  "type": "T",
+  "attrName": "relativeHumidity"
+}
+```
+
+
+#### Output
+
+Payload *null or string*
+
+A `msg.payload` contains a status code.
+
+```
+204
+```
+
+```
+null
+```
+
+## Use value of actionType in payload
+
+It alows to read, update or delete an attribute in NGSIv2 entity.
+
+### Properties
+
+![](https://raw.githubusercontent.com/lets-fiware/node-red-contrib-letsfiware-NGSI/gh-pages/images/attribute-05.png)
+
+-   `name`: A name for a node instance
+-   `Context Broker`: An endpoint of a context broker
+-   `ServicePath`: FIWARE Service Path
+-   `Action type`: value of actionType in payload
+-   `Entity id`: Entity id to read, update or delete an attribute
+-   `Entity type`: Entity type to read, update or delete an attribute
+-   `Attribute name`: Name of attribute name to read, update or delete
+-   `Metadata`: List of metadata names
+-   `Skip forwarding`: If true, Context Broker skips forwarding to Context Providers
+-   `Override metadata`: If true, replace the existing metadata
+-   `Forced update`: If true, it triggers matching subscriptions
+-   `Flow control`: If true, it enables flow control mechanism
+
+### Exmaple
+
+#### Input
+
+Payload  *JSON Object*
+
+When reading an attribute, A `msg.payload` should contain a JSON Object with `actionType` and related information the attribute to be read.
+
+```
+{
+  "actionType": "read",
+  "attrName": "relativeHumidity"
+}
+```
+
+When updating an attribute, A `msg.payload` should contain a JSON Object with `actionType` and `attribute`.
+
+```
+{
+  "actionType": "update",
+  "attribute": {
+    "type": "Number",
+    "value": 1234.5
+  }
+}
+```
+
+When deleting an attribute, A `msg.payload` should contain a JSON Object with `actionType` and related information the attribute to be deleted.
+
+```
+{
+  "actionType": "read",
+  "attrName": "relativeHumidity"
+}
+```
+
+#### Output
+
+Payload *JSON Object*
+
+When reading the attribute, a `msg.payload` contains an object representing the attribute.
+
+```
+{
+  "type":"Number",
+  "value":45,
+  "metadata":{}
+}
+```
+
+Payload *null or number*
+
+When updating and deleting an attribute, a `msg.payload` contains a status code.
+
+```
+204
+```
+
+```
+null
+```

docs/index.md

@@ -13,6 +13,7 @@ Node-RED NGSI integration
 -   [NGSI Entity CRUD](custom_nodes/ngsi_entity_crud.md)
 -   [NGSI Source](custom_nodes/ngsi_source.md)
 -   [NGSI Attributes](custom_nodes/ngsi_attributes.md)
+-   [NGSI Attribute](custom_nodes/ngsi_attribute.md)
 -   [NGSI Attribute value](custom_nodes/ngsi_attribute_value.md)
 -   [NGSI Batch update](custom_nodes/ngsi_batch_update.md)
 -   [NGSI Subscription](custom_nodes/ngsi_subscription.md)