Nest_accfactory

This is a HAP-NodeJS accessory I have developed to allow Nest devices to be used with HomeKit including having support for HomeKit Secure Video on doorbells and camera devices

HomeKit Secure Video Support is disabled by default and needs to be explicitly enabled by the user

Supported Devices

The following Nest devices are supported

• Nest Thermostats (1st gen, 2nd gen, 3rd gen, E, 2020 mirror edition, 4th gen)
• Nest Protects (1st and 2nd gen)
• Nest Temp Sensors (1st gen)
• Nest Cameras (Cam Indoor, IQ Indoor, Outdoor, IQ Outdoor, Cam with Floodlight)
• Nest Doorbells (wired 1st gen)

The accessory supports connection to Nest using a Nest account OR a Google (migrated Nest account) account.

Configuration

Obtaining a Access Token for a Nest Account

If you have a Nest account, you will need to obtain an access token from the Nest web app. Simply go to https://home.nest.com in your browser and log in. Once that's done, go to https://home.nest.com/session in your browser, and you will see a long string that looks like this:

{"2fa_state":"enrolled","access_token":"XXX", ...}

Simply set "access token" in your Nest_config.json file to the value of "access_token" near the start of the string (the XXX), which will be a long sequence of letters, numbers and punctuation beginning with b. There may be other keys labelled access_token further along in the string - please ignore these.

Do not log out of home.nest.com, as this will invalidate your credentials. Just close the browser tab

Obtaining a Google cookie token for a Google Account

Google Accounts are configured using the "GoogleToken" object in Nest_config.json, which contains two fields, "issuetoken" and "cookie", which looks like this:

      "GoogleToken": {
        "issuetoken": "https://accounts.google.com/o/oauth2/iframerpc?action=issueToken...",
        "cookie": "..."
      },

The values of "issueToken" and "cookies" are specific to your Google Account. To get them, follow these steps (only needs to be done once, as long as you stay logged into your Google Account).

1. Open a Chrome browser tab in Incognito Mode (or clear your cache).
2. Open Developer Tools (View/Developer/Developer Tools).
3. Click on 'Network' tab. Make sure 'Preserve Log' is checked.
4. In the 'Filter' box, enter issueToken
5. Go to home.nest.com, and click 'Sign in with Google'. Log into your account.
6. One network call (beginning with iframerpc) will appear in the Dev Tools window. Click on it.
7. In the Headers tab, under General, copy the entire Request URL (beginning with https://accounts.google.com). This is your "issuetoken" in config.json.
8. In the 'Filter' box, enter oauth2/iframe
9. Several network calls will appear in the Dev Tools window. Click on the last iframe call.
10. In the Headers tab, under Request Headers, copy the entire cookie (include the whole string which is several lines long and has many field/value pairs - do not include the cookie: name). This is your "cookie" in Nest_config.json.

Do not log out of home.nest.com, as this will invalidate your credentials. Just close the browser tab

Sample Nest_config.json

Nest_config.json is the configuration file where various options can be. An example of a basic configuration is below

{
    "Connections" : {
        "Nest" : {
            "access_token" : "<nest access token>"
        },
    },
    "HKSV" : true
}

or

{
    "Connections" : {
        "Google" : {
            "issuetoken" : "<google issue token url>",
            "cookie" : "<google cookie>"
        },
    },
    "HKSV" : true
}

An advanced configuration example is below

{
    "Connections" : {
        "Nest" : {
            "access_token" : "<nest session token>"
        },
    },
    "HKSV" : false,
    "SERIAL1" : {
        "Exclude" : true
    },
    "SERIAL2" : {
        "HKSV" : true,
        "MotionCoolDown" : 2
    },
}

Configuration Options

The options available are within the configuration file are listed below. Some of these options can also be on specific devices only

Option	Values	Description	Global/Local
Connections	Nest, Google	Object list of connections to use as per examples above	global
EveApp	true, false	Integration with Evehome App. Default is true	global/local
HomeKitCode		HomeKit pairing code in format of "xxx-xx-xxx". Default is 031-45-154	global/local
Weather	true, false	Creates a "virtual" weather station using Nest weather data. Default is off	global
mDNS	avahi, bonjour, ciao	mDNS advertiser library to use. Default is bonjour	global
HKSV	true, false	Turns HomeKit Secure Video on or off for doorbells and/cameras. Default is off.	global/local
MotionCooldown	seconds or milliseconds	Ignore motion detection for this time once triggered. Default is 1 minute	global/local
PersonCooldown	seconds or milliseconds	Ignore person detection for this time once triggered (Non HKSV only) Default is 2 minutes	global/local
DoorbellCooldown	seconds or milliseconds	Ignore doorbell button pressed for this time once triggered Default is 1 minute	global/local
Exclude	true, false	Exclude a device or all devices by default if used as a globl option	global/local
Option.indoor_chime_switch	true, false	Exposes a switch in HomeKIt to disable/enable indoor chime on Nest Hello. Default is false	local

HomeKit Pairing

Once configured and running, any non-excluded devices can be paired in HomeKit using the default pairing code of 031-45-154 This can be overidden via the configuration file as above

Docker Image

If you would like to try this in a containerised version, please check out the docker hub repository for this project

Caveats

Nest_accfactory is a hobby project of mine, provided as-is, with no warranty whatsoever. I've been running it successfully at my home, but your mileage might vary.