Special considerations when generating names of MQTT topics

When filling in the values for topicName, please adhere to the following guidelines:

• Wildcard characters cannot be used in the names of MQTT topics. We also do not recommend using the $ character in the names of MQTT topics.
• The name of an MQTT topic cannot be blank (it must contain at least one character).
• The names of MQTT topics are case sensitive.
• The names of MQTT topics can contain a blank space character.
• MQTT topics that are separated by only a / character at the beginning or end of the name are considered to be different MQTT topics.
• An MQTT topic name consisting of only a / character is permitted.
• The name of an MQTT topic must not contain the null character (NUL).
• Names of MQTT topics are UTF-8 strings of size that does not exceed 65535 bytes.