homebridge-http-temperature-sensor Plugin

This Homebridge plugin can be used integrate your temperature sensor which has a
http api into HomeKit.

Installation

First of all you need to have Homebridge installed. Refer to the repo for
instructions.
Then run the following command to install homebridge-http-temperature-sensor

``
sudo npm install -g homebridge-http-temperature-sensor
`

Updating the temperature in HomeKit

The _'CurrentTemperature'_ characteristic has the permission to notify the HomeKit controller of state
changes. homebridge-http-temperature-sensor supports two concepts to send temperature changes to HomeKit.

$3

The 'pull' way is probably the easiest to set up and supported in every scenario. homebridge-http-temperature-sensor
requests the temperature of the sensor in an specified interval (pulling) and sends the value to HomeKit.
Look for pullInterval in the list of configuration options if you want to configure it.

$3

When using the 'push' concept, the http device itself sends the updated value to homebridge-http-temperature-sensor
whenever values change. This is more efficient as the new value is updated instantly and
homebridge-http-temperature-sensor does not need to make needless requests when the value didn't actually change.
However because the http device needs to actively notify the homebridge-http-temperature-sensor there is more
work needed to implement this method into your http device.

#### Using MQTT:

MQTT (Message Queuing Telemetry Transport) is a protocol widely used by IoT devices. IoT devices can publish messages
on a certain topic to the MQTT broker which then sends this message to all clients subscribed to the specified topic.
In order to use MQTT you need to setup a broker server (mosquitto is a solid
open source MQTT broker running perfectly on a device like the Raspberry Pi) and then instruct all clients to
publish/subscribe to it.

#### Using 'homebridge-http-notification-server':

For those of you who are developing the http device by themselves I developed a pretty simple 'protocol' based on http
to send push-updates.
How to implement the protocol into your http device can be read in the chapter
Notification Server

Configuration

The configuration can contain the following properties:

##### Basic configuration options:

* accessory \ required: Defines the plugin used and must be set to "HTTP-TEMPERATURE" for this plugin.
* name \ required: Defines the name which is later displayed in HomeKit
* getUrl \urlObject\> required: Defines the url (and other properties when using
and urlObject) to query the current temperature (in celsius) from the sensor. By default it expects the http server
to return the temperature as a float ranging from 0-100 (step 0.1).
* unit \ optional \(Default: "celsius\): Defines unit expected from the http server. The following
are available:
* "celsius": Using celsius to calculate temperature
* "fahrenheit": Using fahrenheit to calculate temperature

##### Advanced configuration options:

* statusPattern \ optional \(Default: "(-?[0-9]{1,3}(\.[0-9]))"): Defines a regex pattern with which the
temperature is extracted from the body of the http response from the getUrl. The group which should
be extracted can be configured with the patternGroupToExtract property.
More about regex pattern.
* patternGroupToExtract \ optional \(Default: 1\): Defines the regex group of which the temperature
is extracted.
* statusCache \ optional \(Default: 0\): Defines the amount of time in milliseconds a queried value
of the _CurrentTemperature_ characteristic is cached before a new request is made to the http device.
Default is 0 which indicates no caching. A value of -1 will indicate infinite caching.

- pullInterval \ optional: The property expects an interval in milliseconds in which the plugin
pulls updates from your http device. For more information read pulling updates.

* mqtt \<mqttObject\> optional: Defines all properties used for mqtt connection (More on MQTT).
For configuration see mqttObject.

- debug \ optional: Enable debug mode and write more logs.

Below are two example configurations. One is using a simple string url and the other is using a simple urlObject.
Both configs can be used for a basic plugin configuration.
`json
{
"accessories": [
{
"accessory": "HTTP-TEMPERATURE",
"name": "Temperature Sensor",

"getUrl": "http://localhost/api/getTemperature"
}
]
}
`
`json
{
"accessories": [
{
"accessory": "HTTP-TEMPERATURE",
"name": "Temperature Sensor",

"getUrl": {
"url": "http://localhost/api/getTemperature",
"method": "GET"
}
}
]
}
`

#### UrlObject

A urlObject can have the following properties:
* url \ required: Defines the url pointing to your http server
* method \ optional \(Default: "GET"\): Defines the http method used to make the http request
* body \ optional: Defines the body sent with the http request. If value is not a string it will be
converted to a JSON string automatically.
* strictSSL \ optional \(Default: false\): If enabled the SSL certificate used must be valid and
the whole certificate chain must be trusted. The default is false because most people will work with self signed
certificates in their homes and their devices are already authorized since being in their networks.
* auth \ optional: If your http server requires authentication you can specify your credential in this
object. When defined the object can contain the following properties:
* username \ required
* password \ required
* sendImmediately \ optional \(Default: true\): When set to true the plugin will send the
credentials immediately to the http server. This is best practice for basic authentication.
When set to false the plugin will send the proper authentication header after receiving an 401 error code
(unauthenticated). The response must include a proper WWW-Authenticate header.
Digest authentication requires this property to be set to false!
* headers \ optional: Using this object you can define any http headers which are sent with the http
request. The object must contain only string key value pairs.
* requestTimeout \ optional \(Default: 20000\): Time in milliseconds specifying timeout (Time to wait
for http response and also setting socket timeout).

Below is an example of an urlObject containing the basic properties:
`json
{
"url": "http://example.com:8080",
"method": "GET",
"body": "exampleBody",

"strictSSL": false,

"auth": {
"username": "yourUsername",
"password": "yourPassword"
},

"headers": {
"Content-Type": "text/html"
}
}
`

#### MQTTObject

A mqttObject can have the following properties:

##### Basic configuration options:

* host \ required: Defines the host of the mqtt broker.
* port \ optional \(Default: 1883\): Defines the port of the mqtt broker.
* credentials \ optional: Defines the credentials used to authenticate with the mqtt broker.
* username \ required
* password \ optional
- subscriptions \