Index
Properties
Optional cacheSizeBytes  
					
					An approximate cache size threshold for the on-disk data. If the cache grows beyond this size, Firestore will start removing data that hasn't been recently used. The size is not a guarantee that the cache will stay below that size, only that if the cache exceeds the given size, cleanup will be attempted.
The default value is 40 MB. The threshold must be set to at least 1 MB, and can be set to CACHE_SIZE_UNLIMITED to disable garbage collection.
Optional experimentalAutoDetectLongPolling    
					
					Configures the SDK's underlying transport (WebChannel) to automatically detect if
								long-polling should be used. This is very similar to experimentalForceLongPolling,
							but only uses long-polling if required.
This setting will likely be enabled by default in future releases and cannot be
						combined with experimentalForceLongPolling.
This setting does not work in a Node.js environment.
Optional experimentalForceLongPolling   
					
					Forces the SDK’s underlying network transport (WebChannel) to use long-polling. Each response from the backend will be closed immediately after the backend sends data (by default responses are kept open in case the backend has more data to send). This avoids incompatibility issues with certain proxies, antivirus software, etc. that incorrectly buffer traffic indefinitely. Use of this option will cause some performance degradation though.
This setting cannot be used with experimentalAutoDetectLongPolling and
							may be removed in a future release. If you find yourself using it to
							work around a specific network reliability issue, please tell us about
						it in https://github.com/firebase/firebase-js-sdk/issues/1674.
This setting does not work in a Node.js environment.
Optional host
The hostname to connect to.
Optional ignoreUndefinedProperties  
					
					Whether to skip nested properties that are set to undefined during
								object serialization. If set to true, these properties are skipped
								and not written to Firestore. If set to false or omitted, the SDK
							throws an exception when it encounters properties of type undefined.
Optional merge
Whether to merge the provided settings with the existing settings. If
								set to true, the settings are merged with existing settings. If
								set to false or left unset, the settings replace the existing
							settings.
Optional ssl
Whether to use SSL when connecting.
Specifies custom configurations for your Cloud Firestore instance. You must set these before invoking any other methods.