[Home](./index.md) > [@snowplow/node-tracker](./node-tracker.md) > [TrackerCore](./node-tracker.trackercore.md) ## TrackerCore interface Export interface containing all Core functions Signature: ```typescript interface TrackerCore ``` ## Properties | Property | Type | Description | | --- | --- | --- | | [addPayloadPair](./node-tracker.trackercore.addpayloadpair.md) | (key: string, value: unknown) => void | Set a persistent key-value pair to be added to every payload | | [track](./node-tracker.trackercore.track.md) | (pb: PayloadBuilder, context?: Array<SelfDescribingJson> \| null, timestamp?: Timestamp \| null) => Payload \| undefined | Call with a payload from a buildX function Adds context and payloadPairs name-value pairs to the payload Applies the callback to the built payload | ## Methods | Method | Description | | --- | --- | | [addGlobalContexts(contexts)](./node-tracker.trackercore.addglobalcontexts.md) | Adds contexts globally, contexts added here will be attached to all applicable events | | [addPayloadDict(dict)](./node-tracker.trackercore.addpayloaddict.md) | Merges a dictionary into payloadPairs | | [addPlugin(configuration)](./node-tracker.trackercore.addplugin.md) | Add a plugin into the plugin collection after Core has already been initialised | | [clearGlobalContexts()](./node-tracker.trackercore.clearglobalcontexts.md) | Removes all global contexts | | [deactivate()](./node-tracker.trackercore.deactivate.md) | Deactivate tracker core including all plugins. This is useful for cleaning up resources or listeners that have been created. Once deactivated, the tracker won't be able to track any events. | | [getBase64Encoding()](./node-tracker.trackercore.getbase64encoding.md) | Get current base64 encoding state | | [removeGlobalContexts(contexts)](./node-tracker.trackercore.removeglobalcontexts.md) | Removes previously added global context, performs a deep comparison of the contexts or conditional contexts | | [resetPayloadPairs(dict)](./node-tracker.trackercore.resetpayloadpairs.md) | Replace payloadPairs with a new dictionary | | [setAppId(appId)](./node-tracker.trackercore.setappid.md) | Set the application ID | | [setBase64Encoding(encode)](./node-tracker.trackercore.setbase64encoding.md) | Turn base 64 encoding on or off | | [setColorDepth(depth)](./node-tracker.trackercore.setcolordepth.md) | Set the color depth | | [setIpAddress(ip)](./node-tracker.trackercore.setipaddress.md) | Set the IP address | | [setLang(lang)](./node-tracker.trackercore.setlang.md) | Set the language | | [setPlatform(value)](./node-tracker.trackercore.setplatform.md) | Set the platform | | [setScreenResolution(width, height)](./node-tracker.trackercore.setscreenresolution.md) | Set the screen resolution | | [setTimezone(timezone)](./node-tracker.trackercore.settimezone.md) | Set the timezone | | [setTrackerNamespace(name)](./node-tracker.trackercore.settrackernamespace.md) | Set the tracker namespace | | [setTrackerVersion(version)](./node-tracker.trackercore.settrackerversion.md) | Set the tracker version | | [setUseragent(useragent)](./node-tracker.trackercore.setuseragent.md) | Set the Useragent | | [setUserId(userId)](./node-tracker.trackercore.setuserid.md) | Set the user ID | | [setViewport(width, height)](./node-tracker.trackercore.setviewport.md) | Set the viewport dimensions |