I just spoke with a Google representative and apparently newer Nest thermostats do support the ability to automatically adjust the humidity based on the outside temperature. He would not directly say which models support it or not, but mine is a 3rd Generation purchased in 2018.
Now, there’s no way to know what percent humidity the Nest is set to (and the app only shows you drops of water and a slider), but at least it is something. In fact, the support rep literally said that the only thing the drops indicate is that more drops means more humidity, but there is no way to know what percentage humidity any of it actually means.
Glad you got it figured out. I don’t think the choose action was available when I started this, but keeping everything in an automation is the way to go. Much cleaner and easier.
Then run apk add php8 and apk add php8-curl to install php8 (with curl extension) into the homeassistant container. php8 comes with the json extension by default.
Create “/config/custom_scripts” folder on your hassio instance
Edit “nest.class.php”. This fools nest to see your automation as a web browser client instead of a curl client. This also moves the temp cookie files to a persistent location “/config/custom_scripts”
line 1474: curl_setopt($ch, CURLOPT_USERAGENT, 'YOUR_USERAGENT_STRING');
line 128: $file = "/config/custom_scripts/nest_php_{$type}_{$suffix}";
line 137: $file = "/config/custom_scripts/nest_php_{$type}_{$unix_user}_{$suffix}";
Edit “update_nest_target_humidity.php”. Specifies your credentials and changes the library path to the same location as this file
line 6: fill in your username
line 7: fill in your password
line 3: require_once dirname(__FILE__) . '/nest.class.php';
Edit “nest-api-php-workaround-login.php”. This puts in your credentials so that you don’t need to enter them everytime this script is executed. This updates the cache file location to /config/custom_scripts/ instead so that it’s persistent across home assistant reboots.
line 11: $username = 'YOUR_USERNAME_HERE';
line 12: $password = 'YOUR_PASSWORD_HERE';
line 14: $cache_file = '/config/custom_scripts/nest_php_cache_' . md5($username . $password);
Upload the files to /config/custom_scripts
Run /usr/bin/php8 /config/custom_scripts/nest-api-php-workaround-login.php from the bash shell prompt in the homeassistant container to generate the session cookie (will need to repeat this on a monthly cadence). Follow the steps from the script prompt
Run /usr/bin/php8 /config/custom_scripts/update_nest_target_humidity.php -10 35 to verify that it runs without an error
Update the shell command to use php8 and run from /config/custom_scripts/