Updated documentation for MQTT connector (#2371)

* update mqtt documentation to the security subsection

* update includes pages

* add new screenshots for mqtt connector

* rename mqtt version compatibility section, add screenshot for generating clientID

* update worker settings for mqtt documentation.

* rewrite mqtt documentation for security subsection.

* add new screenshots for mqtt security subsection documentation

* delete outdated screenshots/md files for mqtt security documentation section

* correct errors inside mqtt documentation, retake some screenshots

* fix small mistyping in mqtt documentation

* write initial data mapping section inside mqtt connector

* add screenshots for data mapping section

* completed the data conversion subsection for the mqtt connector documentation

* add screenshots for usage examples and data conversion subsection

* finish data mapping section with usage examples

* add screenshots for appropriate sections

* delete outdated screenshots and .md files

* Write connect request section for mqtt documentation

* add empty .md files for futher request mapping section

* add empty .md files for futher request mapping section

* delete old connect request section files

* Rewrite disconnect request for mqtt connector

* Add screenshots for disconnect request subsection

* Delete old screenshots

* write documentation for attribute request subsection

* add screenshots for attribute requests subsection

* implement subsection for attribute updates subsection

* add screenshots for attribute updates

* Delete outdated mqtt attribute updates part

* implement basic rpc subsection

* implement subsection for configurable RPC methods to device

* add screenshots for configurable RPC section

* implement documentation section for reserved rpc

* add screenshots for reserved rpc

* remove outdated screenshots

* rewrite iot gateway features mqtt rpc get/set

* correct errors in the mqtt documentation

* Apply requested improvements to MQTT documentation

* Add improvements to MQTT documentation

* fix errors in the mqtt documentation

* retake screenshots, add note for usage examples.

* change screenshots for mqtt rpc's.

Author: Andry925

_includes/templates/iot-gateway/get-set-connector-rpc/mqtt.md

@@ -5,6 +5,7 @@ With the GET method you can subscribe to MQTT topic and receive message from it.
 ```bash
 get requestTopicExpression=<requestTopicExpression>;responseTopicExpression=<responseTopicExpression>;value=<value>;
 ```
+{: .copy-code}
 
 Where:
 - `<requestTopicExpression>` - the topic to publish the request;
@@ -18,54 +19,52 @@ To read the value of the room light level, run this query:
 ```bash
 get requestTopicExpression=data/get_light_level;responseTopicExpression=data/response;value=${params};
 ```
+{: .copy-code}
 
-**Response:**
-
-```json
-{"result":  {"success":true}}
-```
+Also, let's take a look at the data received from the MQTT topic **"data/response"**:
 
 {:refdef: style="text-align: left;"}
 ![image](/images/gateway/get-set-connector-rpc/mqtt-get-set-rpc-1.png)
 {: refdef}
 
-Also, let's take a look at the data received from the MQTT topic **"data/response"**:
-
-{:refdef: style="text-align: left;"}
-![image](/images/gateway/get-set-connector-rpc/mqtt-get-set-rpc-3.jpeg)
-{: refdef}
 
 ### SET method
 
 With the SET method you can publish a message to MQTT topic.
 
 ```bash
-set requestTopicExpression=data/get_light_level;value=${params};
+set requestTopicExpression=data/set_light_level;value=${params};
 ```
+{: .copy-code}
 
 Where:
 - `<requestTopicExpression>` - the topic to publish request;
 - `<value>` - the value to send.
 
 For example, in our case, we know that we can set the value of the room light level to the MQTT topic
-**"data/light_level"**. To set the value of the room light level, run the following query:
+**"sata/light_level"**. To set the value of the room light level, run the following query:
 
 ```bash
 set requestTopicExpression=data/set_light_level;value=80;
 ```
+{: .copy-code}
 
-**Response:**
-
-```json
-{"result":  {"success":true}}
-```
+On the screenshot below, you can see that we have successfully sent the SET request to the MQTT topic **"data/set_light_level"**:
 
 {:refdef: style="text-align: left;"}
 ![image](/images/gateway/get-set-connector-rpc/mqtt-get-set-rpc-2.png)
 {: refdef}
 
-Also, let's take a look at the result in the **"data/light_level"** MQTT topic:
+Also, let's take a look at the result after SET method in the **"data/light_level"** MQTT topic by sending Two way GET RPC request.
+To read the value of the room light level to make sure the room light level is really updated, run this query:
+
+```bash
+get requestTopicExpression=data/get_light_level;responseTopicExpression=data/response;value=${params};
+```
+{: .copy-code}
+
+On the screenshot below, you can see that the room light level value is updated to 80 after the SET request:
 
 {:refdef: style="text-align: left;"}
-![image](/images/gateway/get-set-connector-rpc/mqtt-get-set-rpc-4.jpeg)
+![image](/images/gateway/get-set-connector-rpc/mqtt-get-set-rpc-3.png)
 {: refdef}

_includes/templates/iot-gateway/mqtt-connector/attribute-request-subsection-advanced.md

@@ -1,4 +1,18 @@
-To adding new requests mapping, navigate to the "Requests mapping" tab and click the "plus" icon.
-In the open modal window, select the "Attribute request" type, set a topic filter. Fill in the fields of the "Input request parsing" and "Output request parsing" sections. Then, click "Add".
+In order to add new attribute request mapping, follow these steps:
 
-![image](/images/gateway/mqtt-connector/attribute-request-1-ce.png)
+{% assign AttributesRequest = '
+    ===
+        image: /images/gateway/mqtt-connector/mqtt-gateway-configuring-11-ce.png,
+        title: Click the "**Add mapping**" under "**Requests mapping**" section to add new attribute request mapping.
+    ===
+        image: /images/gateway/mqtt-connector/mqtt-attribute-requests-1.png,
+        title: Select "**Attribute request**" in the **Request type** field, enter the "**Topic filter**"
+    ===
+        image: /images/gateway/mqtt-connector/mqtt-attribute-requests-2.png,
+        title: Configure the **Device name expression**, **Response topic expression**, and **Attribute name expression** fields. 
+        Select the source type for each field (`Message`, `Topic`, or `Constant`) and enter the corresponding values. 
+        You can also set the **Retain** option to determine whether the attribute response message should be retained by the MQTT broker.
+    '
+%}
+
+{% include images-gallery.liquid showListImageTitles="true" imageCollection=AttributesRequest %}

_includes/templates/iot-gateway/mqtt-connector/attribute-request-subsection-basic.md

@@ -1,4 +1,17 @@
-To adding new requests mapping, navigate to the "Requests mapping" tab and click the "plus" icon. 
-In the open modal window, select the "Attribute update" type, and set a device name filter, attribute filter, response value expression, and response topic expression. Then, click “Add”.
+In order to add new attribute update mapping, follow these steps:
 
-![image](/images/gateway/mqtt-connector/attribute-updates-example-basic-1-ce.png)
+{% assign AttributesUpdate = '
+    ===
+        image: /images/gateway/mqtt-connector/mqtt-gateway-configuring-11-ce.png,
+        title: Click the "**Add mapping**" under "**Requests mapping**" section to add new attribute request mapping.
+    ===
+        image: /images/gateway/mqtt-connector/mqtt-attribute-updates-1.png,
+        title: Select "**Attribute update**" in the **Request type** field, enter the "**Device name filter**"
+    ===
+        image: /images/gateway/mqtt-connector/mqtt-attribute-updates-2.png,
+        title: Configure the **Attribute filter**, **Response value expression**, and **Response topic expression** fields.
+        You can also set the **Retain** option to determine whether the attribute response message should be retained by the MQTT broker.
+    '
+%}
+
+{% include images-gallery.liquid showListImageTitles="true" imageCollection=AttributesUpdate %}