Difference between revisions of "OM2M/one/REST API"

Revision as of 12:11, 28 January 2016

Install a rest client

• For this section, you need a REST client to send HTTP request (GET, POST, UPDATE, DELETE) to the OM2M platform.
• You can use the "Client REST Simple" (https://chrome.google.com/webstore/detail/simple-rest-client/fhjcajmcbmldlhcimfajhfbgofnpcjmb), or Postman (http://www.getpostman.com) google chrome extension or any other rest client.

Simple REST client inteface

• The authentification is handle using a specific oneM2M header: X-M2M-Origin. This has to be specified in every request to identify the sender.

Retrieve a resource

• HTTP request:

• HTTP response:

<?xml version="1.0" encoding="UTF-8"?>
<m2m:cb xmlns:m2m="http://www.onem2m.org/xml/protocols" rn="in-name">
    <ty>5</ty>
    <ri>/in-cse</ri>
    <ct>20151104T150228</ct>
    <lt>20151104T150228</lt>
    <acpi>/in-cse/acp-563660429</acpi>
    <cst>1</cst>
    <csi>in-cse</csi>
    <srt>1 2 3 4 5 9 14 15 16 17 23</srt>
    <poa>http://127.0.0.1:8080/</poa>
</m2m:cb>

Create a "MY_SENSOR" application

• Send a HTTP request with the following parameters to create a MY_SENSOR application on the gateway.

• In the creation we have two important headers:
  • Content-Type: this header has 2 informations seperated by a semicolon
    • The format of the exchange, here "application/xml"
    • The resource type to be created, here "ty=2" (2 for AE, see oneM2M spec TS-0004, Table 6.3.3.2.11-1)
  • X-M2M-NM: the name of the resource to be created

<om2m:ae xmlns:om2m="http://www.onem2m.org/xml/protocols">
    <api>app-sensor</api>
    <lbl>Type/sensor Category/temperature Location/home</lbl>
    <rr>false</rr>
</om2m:ae>

• HTTP response:

<?xml version="1.0" encoding="UTF-8"?>
<m2m:ae xmlns:m2m="http://www.onem2m.org/xml/protocols" rn="MY_SENSOR">
    <ty>2</ty>
    <ri>ae-CAE449907766</ri>
    <pi>/in-cse</pi>
    <ct>20151104T151858</ct>
    <lt>20151104T151858</lt>
    <lbl>Type/sensor Category/temperature Location/home</lbl>
    <acpi>/in-cse/acp-89704715</acpi>
    <api>app-sensor</api>
    <aei>CAE449907766</aei>
    <rr>false</rr>
</m2m:ae>

• Here, the application has been created and can be accessed using 2 different URIs:
  • Unstructured URI: this URI is the ri node in the AE representation or present in the Content-Location header in the creation response "/<cse-id>/<id-of-the-resource>". In our case we have "/in-cse/ae-CAE449907766"
  • Structured URI: this URI use the names of the resources hierarchically to get the resource "/<cse-id>/<cse-name>/<hierarchy-of-resource-names>". Here we will simple have "/in-cse/in-name/MY-SENSOR".

The difference between the unstructured URI and the structured one consists in the presence (or not) of the CSE name. Examples: unstructured URI: "/<cse-id>/<id-of-the-resource>", for instance: "/in-cse/ae-123". structured URI: "/in-cse/in-name/<hierarchy-of-resource-names>", for instance: "/in-cse/in-name/name1/name2/name3".

• You can check the created application on the web interface.

Discover resources based on their search strings

• You can discover available resources based on their search strings using the discovery resource. The fu parameter (stands for "Filter Usage") indicate that it is a discovery request. The lbl ("Label") indicate the specific label you what to filter.
• HTTP request:

• HTTP response:

<?xml version="1.0" encoding="UTF-8"?>
<m2m:disres xmlns:m2m="http://www.onem2m.org/xml/protocols">
    <ref ty="2"> <uri-of-the-resource> </ref>
</m2m:disres>

Create a DESCRIPTOR container

• Send a HTTP request with the following parameters to create a DESCRIPTOR container resource under the MY_SENSOR application.

<om2m:cnt xmlns:om2m="http://www.onem2m.org/xml/protocols">
</om2m:cnt>

• HTTP response

<?xml version="1.0" encoding="UTF-8"?>
<m2m:cnt xmlns:m2m="http://www.onem2m.org/xml/protocols" rn="DESCRIPTOR">
    <ty>3</ty>
    <ri>cnt-478855064</ri>
    <pi>/in-cse/ae-CAE449907766</pi>
    <ct>20151104T155844</ct>
    <lt>20151104T155844</lt>
    <acpi>/in-cse/acp-89704715</acpi>
    <cni>0</cni>
    <cbs>0</cbs>
</m2m:cnt>

• As the AE, there is two ways to access the resource:
  • Unstructured URI: which is '/in-cse/cnt-478855064'
  • Structure URI: which is the Structured URI of the AE plus the name of the container, in our case "/in-cse/in-name/MY_SENSOR/DESCRIPTOR"
• Check the created container on the web interface.

Create a description contentInstance

• Send a HTTP request with the following parameters to create a description content instance resource under the "DESCRIPTOR" container.

	
<om2m:cin xmlns:om2m="http://www.onem2m.org/xml/protocols">
    <cnf>message</cnf>
    <con>
        &lt;obj&gt;
            &lt;str name=&quot;type&quot; val=&quot;Temperature_Sensor&quot;/&gt;
            &lt;str name=&quot;location&quot; val=&quot;Home&quot;/&gt;
            &lt;str name=&quot;appId&quot; val=&quot;MY_SENSOR&quot;/&gt;
            &lt;op name=&quot;getValue&quot; href=&quot;/in-cse/MY_SENSOR/DATA/la&quot; 
         in=&quot;obix:Nil&quot; out=&quot;obix:Nil&quot; is=&quot;retrieve&quot;/&gt;
        &lt;/obj&gt;
    </con>
</om2m:cin>

• Check the created content instance on the web interface.

Create a DATA container

• Send a HTTP request with the following parameters to create a "DATA" container resource under the "MY_SENSOR" application.

<om2m:cnt xmlns:om2m="http://www.onem2m.org/xml/protocols">
</om2m:cnt>

• Check the created container on the web interface.

Create a data contentInstance

• Send a HTTP request with the following parameters to create a data content instance resource under the "DATA" container.

	
<om2m:cin xmlns:om2m="http://www.onem2m.org/xml/protocols">
    <cnf>message</cnf>
    <con>
      &lt;obj&gt;
        &lt;str name=&quot;appId&quot; val=&quot;MY_SENSOR&quot;/&gt;
        &lt;str name=&quot;category&quot; val=&quot;temperature &quot;/&gt;
        &lt;int name=&quot;data&quot; val=&quot;27&quot;/&gt;
        &lt;int name=&quot;unit&quot; val=&quot;celsius&quot;/&gt;
      &lt;/obj&gt;
    </con>
</om2m:cin>

• Check the created content instance on the web interface.

Subscribe to MY_SENSOR data

• Download the monitor server sample from this link: Monitor.
• Start the Monitor server using the following command:

> java -jar monitor.jar

• The monitor starts listening on port=1400 and context=/monitor.

Monitor console: the server is started

• Send a HTTP request with the following parameters to create a "Subscription" resource for receive asynchronously events from "MY_SENSOR" application.
• The monitor listening URL (http://127.0.0.1:1400/monitor) should be added on the "nu" tag of the subscription representation.

<m2m:sub xmlns:m2m="http://www.onem2m.org/xml/protocols">
    <nu>http://localhost:1400/monitor</nu>
    <nct>2</nct>
</m2m:sub>

• Check the created subscription on the web interface.

• Create a new event content instance resource under the "DATA" container.
• The new event is published to interested subscribers by the gateway.
• Here is an example of the "Notify" XML representation:

<?xml version="1.0" encoding="UTF-8"?>
<m2m:sgn xmlns:m2m="http://www.onem2m.org/xml/protocols">
   <nev>
      <rep rn="cin_name1">
         <ty>4</ty>
         <ri>cin-46677406</ri>
         <pi>/in-cse/cnt-397256037</pi>
         <ct>20151104T162611</ct>
         <lt>20151104T162611</lt>
         <st>0</st>
         <cnf>message</cnf>
         <cs>11</cs>
         <con>hello world</con>
      </rep>
      <rss>1</rss>
   </nev>
   <sud>false</sud>
   <sur>/in-cse/in-name/MY_SENSOR/DATA/SUB_MY_SENSOR</sur>
</m2m:sgn>

• The Monitor receives a "Notify" resource including the new "ContentInstance".
• Remember that the "Notify" resource has a generic structure to support notifications for other type of resources such as "AE", "Container", "Group", "AccessControlPolicy", etc.