Bubblewrap CLI
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Bubblewrap is a Command Line Interface (CLI) that helps developers to create
a Project for an Android application that launches an existing Progressive Web App (PWA) using a
Trusted Web Activity (TWA).
Requirements
Setting up the Environment
When running Bubblewrap for the first time, it will offer to automatically download and install
external dependencies. This is the recommended setup, but it's possible to
manually setup the environment.
Quickstart Guide
Installing Bubblewrap
npm i -g @bubblewrap/cli
:warning: Warning: Don't use sudo npm i -g @bubblewrap/cli
to install Bubblewrap. Using npm
commands with sudo
can create different kinds of problems and should be avoided (see
here and
here).
Initializing an Android Project
Generate an Android project from an existing Web Manifest:
bubblewrap init --manifest https://my-twa.com/manifest.json
When initalizing a project, Bubblewrap will download the Web Manifest and ask you to confirm
the values that should be used when building the Android project.
It will also ask you for the details needed to generate a signing key, used to sign the
app before uploading to the Play Store.
:grey_exclamation: Even though we recommend Bubblewrap for building and generating a signed
APK, the output from the init
command is a regular Android project that can be opened
and built using Android Studio. Please, refer to the
documentation to build and sign
applications using Android Studio.
Building the Android Project
bubblewrap build
When building the project for the first time, the Android Build Tools will need to be installed.
The tool will inkove the installation process for the build tools. Make sure to read and accept
the license agreement before proceeding. This process will install the other required files inside the directory/decompressed
root directory of the android CLI package.
As a result of the build step, the tool will generate a signed APK (app-release-signed.apk
)
that can be used for testing the app and a signed AppBundle (./app-release-bundle.aab
) that can be uploaded to the Play Store. You will also need to deploy a Digital Asset Links file to
validate your domain. The
TWA Quick Start Guide
explains how to extract the information needed to generate it.
Commands
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The diagram above shows which commands (in the black boxes) take as input or produce as output various files (in white ovals).
An arrow leading to a file means "creates or modifies" and an arrow leading to a command means "is used as input".
init
Usage:
Initializes an Android project for Trusted Web Activity from a Web Manifest. The init script will
parse the Web manifest and generate default values for the Android project, where possible. It
will prompt the user to confirm or input values where one could not be generated.
bubblewrap init --manifest="<web-manifest-url>" [--directory="<path-to-output-location>"] [--chromeosonly]
Options:
--directory
: path where to generate the project. Defaults to the current directory.--chromeosonly
: this flag specifies that the build will be used for Chrome OS only and prevents non-Chrome OS devices from installing the app.--alphaDependencies
: enables features that depend on upcoming version of the Android library
for Trusted Web Activity or that are still unstable.
build
Builds the project into a final APK that can be uploaded to the Play Store.
The command will ask the user for they key store passwords. Alternatively, users can set the
passwords as enviromental variables, which allows running build
as part of a continuous integration.
Set BUBBLEWRAP_KEYSTORE_PASSWORD
for the key store password and BUBBLEWRAP_KEY_PASSWORD
as the key password.
Usage:
bubblewrap build [--skipPwaValidation] [--skipSigning] [--manifest="<path-twa-manifest>"] [--signingKeyPath="<path-to-signing-key>"] [--signingKeyAlias="<key-alias>"]
Options:
--skipPwaValidation
: skips validating the wrapped PWA against the Quality Criteria.--skipSigning
: skips signing the built APK and App Bundle. Other signing-related flags are ignored when this is used.--signingKeyPath
: path to keystore to use for signing the built APK and App Bundle. Overrides signingKey.path specified in twa-manifest.json
.--signingKeyAlias
: key name. Overrides signingKey.alias specified in twa-manifest.json
.--manifest
: directory where the client should look for twa-manifest.json
.
update
Regenerates the Android project files from a twa-manifest.json
file.
:warning: Warning: Bubblewrap doesn't expect the generated Android project to be updated using
external editors. Any files added manually to the Android project will be deleted or overwritten
when update
is executed. Changes to twa-manifest.json
are preserved.
Usage:
bubblewrap update [--appVersionName="<version-string>"] [--skipVersionUpgrade] [--manifest="<path-twa-manifest>"]
Options:
--appVersionName
: version name to be used on on the upgrade. Ignored if --skipVersionUpgrade
is used.--skipVersionUpgrade
: skips upgrading appVersion
and appVersionCode
.--manifest
: directory where the client should look for twa-manifest.json
.
validate
Validates a PWA agains the Quality Criteria for being using in a Trusted Web Activity.
Usage:
bubblewrap validate --url=[pwa-url]
install
Install the application generated in the output command to a device connected for debugging.
Usage:
bubblewrap install [--apkFile="/path-to-apk/apkfile.apk"]
Options:
--apkFile
: path to the APK file to be installed. Defaults to ./app-release-signed.apk
.--verbose
: prints the adb command being executed.
help
Displays a list of commands and options.
Usage:
bubblewrap help
doctor
Validates that the jdk and the androidSdk are located at the path specified in your config
and that they are at the correct version.
Usage:
bubblewrap doctor
updateConfig
Sets the paths of the jdk or the androidSdk to the given paths.
Usage:
bubblewrap updateConfig --jdkPath="/path-to-jdk" --androidSdkPath="/path-to-androidSdk"
Options:
--jdkPath
: sets the jdk's path to the path given.--androidSdkPath
: sets the androidSdk's path to the path given.
merge
Merges the user's web manifest into their twaManifest.json.
Usage:
bubblewrap merge --ignore [fields-list]
Options:
--appVersionName
: version name to be used on on the upgrade. Ignored if --skipVersionUpgrade
is used.--skipVersionUpgrade
: skips upgrading appVersion
and appVersionCode
.--ignore
: Ignores all of the fields on the list. Accepts all of the possible fields
in the Web Manifest.
Manually setting up the Environment
Get the Java Development Kit (JDK) 8.
The Android Command line tools requires the correct version of the JDK to run. To prevent version
conflicts with a JDK version that is already installed, Bubblewrap uses a JDK that can unzipped in
a separate folder.
Download a version of JDK 8 that is compatible with your OS from
AdoptOpenJDK
and extract it in its own folder.
:warning: Warning: Using a version lower than 8 will make it impossible to compile the project and higher
versions are incompatible with the Android command line tools.
Get the Android command line tools
Download a version of Android command line tools that is compatible with your OS from
https://developer.android.com/studio#command-tools.
Create a folder and extract the downloaded file into it. This will further install the androidSdk and android SDK manager without needing to install the whole Android IDE.
Tell Bubblewrap where the JDK and Android command line tools are
When running bubblewrap
for the first time, it will ask where it can find the JDK and Android command
line tools. So, take note of the location where both were decompressed.
To ensure if you are taking note of the correct location, check if each directory contains the following files:
- On Windows and Linux, the correct OpenJDK path should contain
bin
, include
,lib
, etc. On MacOS,
the directory should contain the Contents
subdirectory. - The AndroidSDK path should contain
tools
which should have bin
, cli
Updating the location of the JDK and / or the Android command line tools.
If the location for the JDK or the Android command line tools have been setup with the wrong path or
if their location has changed after the initial configuration, the location for either of those can
be changed by editing the configuration file at ${USER_HOME}/.bubblewrap/config.json
.
Sample config.json
{
"jdkPath":"\\user\\home\\bubblewrap-user\\open-jdk",
"androidSdkPath":"\\user\\home\\bubblewrap-user\\android-cli"
}
(Note : Make sure you don't have spaces
in the androidSdkPath. Check this link for more details.)
Contributing
See CONTRIBUTING for more.
License
See LICENSE for more.
Disclaimer
This is not a Google product.