// Create Channel Example

{
  "uri": "/my/hello/world",
  "channelType": "Publication",
  "description": "Example for hello world video"
}

Publication Session id: 310126d4-2f9e-411e-b6be-a5381ae26e65
Subscription Session id: 84f60f0b-ecfe-4fc0-8525-4deb04aed9a2

// Create Subscription Session
{
  "topics": [
    "my-example"
  ],
  "listenerUrl": null,
  "filterExpressions": []
}

// Post Message
{
  "messageContent": {
    "mediaType": "text/plain",
    "content": "Hello World!"
  },
  "topics": [
    "my-example"
  ],
  "expiry": "PT24H"
}

{
  "messageContent": {
    "content": {"say": "Hello World!"}
  },
  "topics": [
    "my-example"
  ],
  "expiry": "PT24H"
}

{
  "messageContent": {
    "mediaType": "application/xml",
    "content": "<say>Hello World!</say>"
  },
  "topics": [
    "my-example"
  ],
  "expiry": "PT24H"
}

{
  "messageContent": {
    "mediaType": "application/xml",
    "contentEncoding": "base64",
    "content": "PHNheT5IZWxsbyBXb3JsZCE8L3NheT4="
  },
  "topics": [
    "my-example"
  ],
  "expiry": "PT24H"
}