Description

• Create a composite bundle out of multiple MiniApps and start the react-native local packager to serve this bundle so that it can be loaded within the native host application

Syntax

ern start

Note

If you do not pass an argument to this command, you are prompted to select a native application version from the Cauldron. The command uses whatever MiniApp versions are curently declared in this native application version container to launch the command.

Options

--baseComposite <compositePath>

• Git or File System path, to the custom Composite repository (refer to the [custom Composite] documentation for more information).

--compositeDir <compositeDir>

• Directory in which to generate the composite

• The directory should either not exist (will be created) or be empty

• By default the composite will be generated in a temorary directory

--descriptor/-d <descriptor>

• Target a specific native application version, associated to the provided complete native application descriptor.

• This option uses whatever MiniApp versions are currently declared in this native application version container to launch the command.

--miniapps/-m <miniapps>

• Specify one or more MiniApps to launch this command

• The command packages all the provided MiniApps in a composite bundle and starts the react-native packager.

• You can use any valid Yarn package descriptor for the MiniApps provided to this command, including Git and other file system path schemes.

--jsApiImpls

• Specify one or more JS API Implementations to include

--watchNodeModules/-w <nodemodules>

• A list of one or more directory name(s) from node_modules that should be watched for changes.

--extraJsDependencies/-e <jsdependencies>

• Additional JavaScript dependencies to add to the composite JavaScript bundle.

--host

• Host or ip to launch the local packager on (default: localhost)

--port

• Port on which the local packager should listen on (default: 8081)

--resetCache\

• Indicates whether to reset the React Native cache prior to bundling

Platform Specific Options

Android

--activityName/-a <activity name>

• Specify Android Activity to launch.

--launchFlags <string>

• Extra options passed to am start command when launching the application (correspond to the Launch Flags in Run/Debug Configurations of application in Android Studio, as can be seen on screenshot below)

• Make sure to use = on the command line to provide this option, and keep the string in quotes. For example --launchFlags="--es aKey aStringValue --ei anotherKey 1"

--packageName/-p <packagename>

• Android application package name to avoid conflict with the names of classes or interfaces.

iOS

--bundleId/-b

• iOS Bundle Identifier unique to your app.

--launchArgs

• Arguments to pass to the application when launching it (correspond to the Arguments Passed On Launch in application scheme run config in XCode as can be seen on screenshot below).

• Make sure to use = on the command line to provide this option, and keep the string in quotes. For example --launchArgs="-ArgA -ArgB"

--launchEnvVars

• Environment variables to pass to the application when launching it (correspond to the Environment Variables in application scheme run config in XCode as can be seen on screenshot below).

• Make sure to use = on the command line to provide this option, and keep the string in quotes. The string should contain key=value pairs delimited by spaces. For example --launchEnvVars="aKey=aValue anotherKey=anotherValue"

• Default false

Binary Store Specific Options

--disableBinaryStore

• Setting this option will bypass retrieval and installation of the binary from the Binary Store.

• It can be useful in case you want to use ern start command in conjunction with your own mobile application native binary, build locally on your workstation or retrieved from a specific location.

--flavor

• Flavor of the binary to retrieve from the store.

• The binary of a specific application version (for ex 1.0.0) can have different flavors, representing different build types of the same application version (for example Dev/Prod/QA ...).

Remarks

• This command can be used to package multiple MiniApps inside a single composite bundle and automatically start the react-native local packager to serve this bundle.

• Use this command when you need to launch and develop or debug your MiniApps from within a native host application which contains other MiniApps along with your MiniApp.

• This command works with the ern link command. For additional information, see the documentation for the ern link command.

• When using a binary store, file watcher will be started after the binary is retrieved and installed on the simulator/device. If you are using a binary store and don't want to launch binary from the store, please make sure to use the --disableBinaryStore option. Otherwise, file watcher will not be started.

Related commands

​ern link | Link to a MiniApp directory

[custom Composite]: ./platform-parts/composite/index.md