Teams JavaScript client library

The Microsoft Teams JavaScript client library (TeamsJS) can help you create hosted experiences in Teams, Microsoft 365 app, and Outlook, where your app content is hosted in an iFrame. The library is helpful for developing apps with the following Teams capabilities:

Starting with version 2.0.0, the existing TeamsJS library (@microsoft/teams-js, or simply TeamsJS) has been refactored to enable Teams apps to run in Outlook and Microsoft 365 app, in addition to Microsoft Teams. From a functional perspective, the latest version of TeamsJS supports all existing (v.1.x.x) Teams app functionality while adding the optional ability to host Teams apps in Outlook and Microsoft 365 app.

Here's the current versioning guidance for various app scenarios:

TeamsJS version App manifest version Next steps
Teams apps extended to Microsoft 365 / Outlook TeamsJS v.2.0 or later 1.13 or later Extend a Teams app to run across Microsoft 365 or Create a new Microsoft 365 app
Existing Teams-only apps Update to TeamsJS v.2.0 when possible (v.1.12 is still supported*) 1.12 Understand TeamsJS backwards compatibility and Update to TeamsJS v.2.0
New Teams-only apps TeamsJS v.2.0 or later 1.12 Create a new Teams app using Teams Toolkit

*Use the latest TeamsJS (v.2.0 or later) whenever possible, in order to leverage from the latest improvements and new feature support including Teams-only apps. TeamsJS v.1.12 continue to be supported, however, no new features or improvements will be added. The 1.12 and 1.13 schemas are otherwise the same. For more information, see TeamsJS library.

The remainder of this article will walk you through the structure and latest updates to the TeamsJS library.

Microsoft 365 support (running Teams apps in Microsoft 365 and Outlook)

TeamsJS v.2.0 introduces the ability for certain types of Teams apps to run across the Microsoft 365 ecosystem. Currently, other Microsoft 365 application hosts (including Microsoft 365 app and Outlook) for Teams apps support a subset of the application types and capabilities you can build for the Teams platform. This support will expand over time. For a summary of host support for Teams apps, see TeamsJS capability support across Microsoft 365.

What's new in TeamsJS version 2.x.x

There are two significant changes between TeamsJS 1.x.x versions and v.2.0.0 and later:

  • Callback functions now return Promise objects. Most functions with callback parameters in TeamsJS v.1.12 have been modernized to return a JavaScript Promise object for improved handling of asynchronous operations and code readability.

  • APIs are now organized into capabilities. You can think of capabilities as logical groupings of APIs that provide similar functionality, such as authentication, dialog, chat, and calendar. Each namespace represents a separate capability.

Tip

You can use the Teams Toolkit extension for Microsoft Visual Studio Code to simplify the TeamsJS v.2.0 update process for an existing Teams app.

Backwards compatibility

Once you start referencing @microsoft/teams-js@2.0.0 (or later) from an existing Teams app, you'll see deprecation warnings for any code calling APIs that have changed.

An API translation layer (mapping v.1 to v.2 TeamsJS API calls) is provided to enable existing Teams apps to continue working in Teams until they're able to update application code to use the TeamsJS v.2 API patterns.

Teams-only apps

Even if you intend your app to only run in Teams (and not Microsoft 365 app and Outlook), best practice is to start referencing the latest TeamsJS (v.2.0 or later) as soon as convenient, in order to benefit from the latest improvements, new features, and support (even for Teams-only apps). TeamsJS v.1.12 will continue to be supported, but no new features or improvements will be added.

Once you're able, the next step is to update existing application code with the changes described in this article. In the meantime, the v.1 to v.2 API translation layer provides backwards compatibility, ensuring your existing Teams app continues to work in TeamsJS version 2.0.

Teams apps running across Microsoft 365

Enabling an existing Teams app to run in Outlook and Microsoft 365 requires all of the following:

  1. Dependency on TeamsJS version 2.x.x ( @microsoft/teams-js@2.0.0) or later,

  2. Modifying existing application code according to the required changes described in this article, and

  3. Updating your app manifest (previously called Teams app manifest) to version 1.13 or later.

For more info, see Extend Teams apps across Microsoft 365.

Callbacks converted to promises

Note

The getTabInstances API isn't implemented on Teams mobile.

Teams APIs that previously took a callback parameter have been updated to return a JavaScript Promise object. These include the following APIs:

app.getContext, app.initialize, appInstallDialog.openAppInstallDialog, app.openLink, authentication.authenticate, authentication.getAuthToken, authentication.getUser, authentication.registerAuthenticationHandlers was removed to support using Promises, calendar.openCalendarItem, calendar.composeMeeting, call.startCall, chat.getChatMembers, conversations.openConversation, location.getLocation, location.showLocation, mail.openMailItem, mail.composeMail, pages.backStack.navigateBack, pages.navigateCrossDomain, pages.navigateToTab, pages.tabs.getMruTabInstances, pages.tabs.getTabInstances, pages.getConfig, pages.config.setConfig, pages.backStack.navigateBack, people.selectPeople, teams.fullTrust.getConfigSetting, teams.fullTrust.joinedTeams.getUserJoinedTeams

You'll need to update the way your code calls any of these APIs to use Promises. For example, if your code is calling a Teams API like this:

This code:

import microsoftTeams from "@microsoft/teams-js";

microsoftTeams.getContext((context) => { /* ... */ });

Needs to be updated to:

import { app, Context } from "@microsoft/teams-js";

app.getContext().then((context) => {
    /*...*/
});

...or the equivalent async/await pattern:

import { app, Context } from "@microsoft/teams-js";

async function example() {
  const context = await app.getContext();
  /*...*/
}

Tip

When you use Teams Toolkit to update to TeamsJS v.2.0, the required updates are flagged for you with TODO comments in your client code.

APIs organized into capabilities

A capability is a logical grouping (via namespace) of APIs that provide similar functionality. You can think of Microsoft Teams, Outlook, and Microsoft 365 app, as hosts to your tab app. A host supports a given capability if it supports all the APIs defined within that capability. A host can't partially implement a capability. Capabilities can be feature- or content-based, such as authentication, or dialog. There are also capabilities for application types such as pages, and other groupings.

Starting with TeamsJS v.2.0, APIs are defined as functions in a JavaScript namespace whose name matches their required capability. For example, if an app is running in a host that supports the dialog capability, then the app can safely call APIs such as dialog.open (in addition to other dialog-related APIs defined in the namespace). If an app attempts to call an API that's not supported in that host, the API generates an exception.

Tip

Check for host support of a given capability at runtime by calling the isSupported() function on that capability (namespace).

Differentiate your app experience

You can check for host support of a given capability at runtime by calling the isSupported() function on that capability (namespace). It will return true if it's supported and false if not, and you can adjust app behavior as appropriate. This allows your app to light up UI and functionality in hosts that support it, while continuing to run for hosts that don't.

The name of the host your app is running in is exposed as a hostName property on the Context interface (app.Context.app.host.name), which can be queried at runtime by calling getContext. It's also available as a {hostName} URL placeholder value. Best practice is to use the hostName mechanism sparingly:

  • Don't assume certain functionality is or isn't available in a host based on the hostName property value. Instead, check for capability support (isSupported).
  • Don't use hostName to gate API calls. Instead, check for capability support (isSupported).
  • Do use hostName to differentiate the theme of your application based on the host it's running in. For example, you can use Microsoft Teams purple as the main accent color when running in Teams, and Outlook blue when running in Outlook.
  • Do use hostName to differentiate messages shown to the user based on which host it's running in. For example, show Manage your tasks in Microsoft 365 when running in Microsoft 365 on the web, and Manage your tasks in Teams when running in Teams.

Namespaces

Starting with TeamsJS v.2.0, APIs are organized into capabilities by way of namespaces. Several new namespaces of particular importance are app, pages, dialog, and teamsCore.

app namespace

The app namespace contains top-level APIs required for overall app usage, across Teams, Microsoft 365 app, and Outlook. All the APIs from various other TeamsJS namespaces have been moved to the app namespace as of TeamsJS v.2.0:

Original namespace global (window) New namespace app
executeDeepLink app.openLink (renamed)
initialize app.initialize
getContext app.getContext
registerOnThemeChangeHandler app.registerOnThemeChangeHandler
Original namespace appInitialization New namespace app
appInitialization.notifyAppLoaded app.notifyAppLoaded
appInitialization.notifySuccess app.notifySuccess
appInitialization.notifyFailure app.notifyFailure
appInitialization.notifyExpectedFailure app.notifyExpectedFailure
appInitialization.FailedReason enum app.FailedReason
appInitialization.ExpectedFailureReason enum app.ExpectedFailureReason
appInitialization.IFailedRequest enum app.IFailedRequest
appInitialization.IExpectedFailureRequest enum app.IExpectedFailureRequest
pages namespace

The pages namespace includes functionality for running and navigating webpages within various Microsoft 365 hosts, including Teams, Microsoft 365 app, and Outlook. It also includes several subcapabilities, implemented as subnamespaces.

Original namespace global (window) New namespace pages
setFrameContext pages.setCurrentFrame (renamed)
initializeWithFrameContext pages.initializeWithFrameContext
registerFocusEnterHandler pages.registerFocusEnterHandler
registerFullScreenHandler pages.registerFullScreenHandler
navigateCrossDomain pages.navigateCrossDomain
returnFocus pages.returnFocus
shareDeepLink pages.shareDeepLink
Original namespace settings New namespace pages
settings.getSettings pages.getConfig (renamed)
pages.tabs
Original namespace global (window) New namespace pages.tabs
getTabInstances pages.tabs.getTabInstances
getMruTabInstances pages.tabs.getMruTabInstances
Original namespace navigation New namespace pages.tabs
navigation.navigateToTab pages.tabs.navigateToTab
pages.config
Original namespace settings New namespace pages.config
settings.setSettings pages.config.setConfig (renamed)
settings.setValidityState pages.config.setValidityState
settings.initialize pages.config.initialize
settings.registerOnSaveHandler pages.config.registerOnSaveHandler
settings.registerOnRemoveHandler pages.config.registerOnRemoveHandler
settings.Settings interface pages.config.Config (renamed)
settings.SaveEvent interface pages.config.SaveEvent (renamed)
settings.RemoveEvent interface pages.config.RemoveEvent (renamed)
settings.SaveParameters interface pages.config.SaveParameters (renamed)
settings.SaveEventImpl interface pages.config.SaveEventImpl (renamed)
Original namespace global (window) New namespace pages.config
registerChangeConfigHandler pages.config.registerChangeConfigHandler (renamed)
pages.backStack
Original namespace navigation New namespace pages.backStack
navigation.navigateBack pages.backStack.navigateBack
Original namespace global (window) New namespace pages.backStack
registerBackButtonHandler pages.backStack.registerBackButtonHandler
pages.appButton
Original namespace global (window) New namespace pages.appButton
registerAppButtonClickHandler pages.appButton.onClick (renamed)
registerAppButtonHoverEnterHandler pages.appButton.onHoverEnter (renamed)
registerAppButtonHoverLeaveEnter pages.appButton.onHoverLeave (renamed)
FrameContext interface pages.appButton.FrameInfo (renamed))
dialog namespace

The TeamsJS tasks namespace has been renamed to dialog, and the following APIs have been renamed:

Original namespace tasks New namespace dialog
tasks.startTask dialog.open (renamed)
tasks.submitTasks dialog.submit (renamed)
tasks.updateTasks dialog.update.resize (renamed)
tasks.TaskModuleDimension enum dialog.DialogDimension (renamed)
tasks.TaskInfo interface dialog.DialogInfo (renamed)

Additionally, this capability has been split into a main capability (dialog) for supporting HTML-based dialogs, and a subcapability for bot-based dialogs, dialog.bot.

teamsCore namespace

To generalize the TeamsJS library to run other Microsoft 365 hosts such as Microsoft 365 app and Outlook, Teams-specific functionality (originally in the global namespace) has been moved to a teamsCore namespace:

Original namespace global (window) New namespace teamsCore
enablePrintCapability teamsCore.enablePrintCapability
print teamsCore.print
registerOnLoadHandler teamsCore.registerOnLoadHandler
registerBeforeUnloadHandler teamsCore.registerBeforeUnloadHandler

Updates to the Context interface

The Context interface has been moved to the app namespace and updated to group similar properties for better scalability as it runs in Outlook and Microsoft 365 app, in addition to Teams.

A new property app.Context.app.host.name has been added to enable tabs to differentiate user experience depending on the host application.

You can also visualize the changes by reviewing the transformLegacyContextToAppContext function in the TeamsJS version 2.x.x source (app.ts file).

Original name in Context interface New location in app.Context
appIconPosition app.Context.app.iconPositionVertical
appLaunchId NOT IN TeamsJS v.2.0
appSessionId app.Context.app.sessionId
channelId app.Context.channel.id
channelName app.Context.channel.displayName
channelRelativeUrl app.Context.channel.relativeUrl
channelType app.Context.channel.membershipType
chatId app.Context.chat.id
defaultOneNoteSectionId app.Context.channel.defaultOneNoteSectionId
entityId app.Context.page.id
frameContext app.Context.page.frameContext
groupId app.Context.team.groupId
hostClientType app.Context.app.host.clientType
hostTeamGroupId app.Context.channel.ownerGroupId
hostTeamTenantId app.Context.channel.ownerTenantId
isCallingAllowed app.Context.user.isCallingAllowed
isFullScreen app.Context.page.isFullScreen
isMultiWindow app.Context.page.isMultiWindow
isPSTNCallingAllowed app.Context.user.isPSTNCallingAllowed
isTeamArchived app.Context.team.isArchived
locale app.Context.app.locale
loginHint app.Context.user.loginHint
meetingId app.Context.meeting.id
osLocaleInfo app.Context.app.osLocaleInfo
parentMessageId app.Context.app.parentMessageId
ringId app.Context.app.host.ringId
sessionId app.Context.app.host.sessionId
sourceOrigin app.Context.page.sourceOrigin
subEntityId app.Context.page.subPageId
teamId app.Context.team.internalId
teamSiteDomain app.Context.sharepointSite.domain
teamSitePath app.Context.sharepointSite.path
teamSiteUrl app.Context.sharepointSite.url
teamTemplateId app.Context.team.templateId
teamType app.Context.team.type
tenantSKU app.Context.user.tenant.teamsSku
tid app.Context.user.tenant.id
upn app.Context.user.userPrincipalName
userClickTime app.Context.app.userClickTime
userFileOpenPreference app.Context.app.userFileOpenPreference
userLicenseType app.Context.user.licenseType
userObjectId app.Context.user.id
userTeamRole app.Context.team.userRole
NA app.Context.app.host.name

Updating to TeamsJS version 2.0

The easiest way to update your Teams app with TeamsJS version 2.0.x is to use the Teams Toolkit extension for Visual Studio Code. This section will walk you through the steps to do that. If you prefer to manually update your code, see the Callbacks converted to promises and APIs organized into capabilities sections for more details on required API changes.

1. Install the latest Teams Toolkit Visual Studio Code extension

In the Visual Studio Code Extensions Marketplace, search for Teams Toolkit and install the latest version.

2. Update TeamsJS references

To run in Outlook and Microsoft 365 app, your app will need to depend on the npm package @microsoft/teams-js@2.0.0 (or later). To perform these steps manually, and for more information on the API changes, see the following sections on Callbacks converted to promises and APIs organized into capabilities.

  1. Ensure you have the latest Teams Toolkit (version 2.10.0 or later)
  2. Open the Command palette: Ctrl+Shift+P
  3. Run the command Teams: Upgrade Teams JS SDK references to support Outlook and Microsoft 365 apps

After completion, the utility will have updated your package.json file with the TeamsJS version 2.x.x (@microsoft/teams-js@2.0.0 or later) dependency, and your *.js/.ts and *.jsx/.tsx files will be updated with:

Important

Code inside html files is not supported by the upgrade tooling and will require manual changes.

3. Update the app manifest (optional)

If you're updating a Teams app to run in Microsoft 365 app and Outlook, you'll also need to update the app manifest to version 1.13 or later. You can do this easily with Teams Toolkit, or manually.

  1. Open the Command palette: Ctrl+Shift+P
  2. Run Teams: Upgrade Teams manifest to support Outlook and Microsoft 365 apps command and select your app manifest file. Changes will be made in place.

If you used Teams Toolkit to create your personal app, you can also use it to validate the changes to your app manifest file and identify any errors. Open the command palette Ctrl+Shift+P and find Teams: Validate manifest file or select the option from the Deployment menu of the Teams Toolkit (look for the Teams icon on the left side of Visual Studio Code).

Teams Toolkit 'Validate manifest file' option under 'Deployment' menu

Next steps