Joshua Rowe

Joshua Rowe


Runs Flutter integration tests on real devices in cloud

A sylph is a mythological invisible being of the air. Wikipedia


Sylph is a command line utility for running Flutter integration and end-to-end tests on pools of real iOS and Android devices in the cloud. Sylph runs on mac, linux and windows and also in a CI environment.

Sylph works with AWS Device Farm for up to hundreds of Android and iOS devices in a single run.


pub global activate sylph



or, if not using the default config file:

sylph -c <path to config file>

General usage:

usage: sylph [--help] [--config <config file>] [--devices <all|android|ios>] [--verbose]

sample usage: sylph

-c, --config=<sylph.yaml>          Path to config file.
                                   (defaults to "sylph.yaml")

-d, --devices=<all|android|ios>    List devices available in cloud.
                                   [all, android, ios]

-v, --verbose                      Noisy logging, including all shell commands executed.
-h, --help                         Display this help information.



Install AWS Command Line Interface (AWS CLI)


curl "" -o ""
sudo ./awscli-bundle/install -i /usr/local/aws -b /usr/local/bin/aws


pip install  awscli 

For alternative install options see:

AWS CLI Credentials

Configure the AWS CLI credentials:

$ aws configure
AWS Secret Access Key [None]: wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
Default region name [None]: us-west-2
Default output format [None]: json

For alternative configuration options see:


Confirm AWS CLI is installed and configured correctly by running an AWS command. For example, the following command should generate output:

aws devicefarm list-projects


Configuration information is passed to Sylph using a configuration file. The default config file is called sylph.yaml:

# Config file for Flutter tests on real device pools.
# Auto-creates projects and device pools if needed.
# Configures android and ios test runs.
# Builds app, uploads and runs tests.
# Then monitors tests, returns final pass/fail result and downloads artifacts.
# Note: assumes the 'aws' command line utility is logged-in.
# Note: to build the debug iOS app, certain environment variables are required.

# sylph config
tmp_dir: /tmp/sylph
artifacts_dir: /tmp/sylph_artifacts
# local timeout per device farm run
sylph_timeout: 720 # seconds approx
# run on ios and android pools concurrently (for faster results)
concurrent_runs: true

# device farm config
project_name: App Integration Tests
default_job_timeout: 10 # minutes, set at project creation


  - pool_name: android pool 1
    pool_type: android
      - name: Google Pixel 2
        model: Google Pixel 2
        os: 8.0.0

  - pool_name: ios pool 1
    pool_type: ios
      - name: Apple iPhone X
        model: A1865
        os: 11.4


  - test_suite: example tests 1
    main: test_driver/main.dart
      - test_driver/main_test.dart
      - android pool 1
      - ios pool 1
    job_timeout: 15 # minutes, set per job, over-rides default job timeout above

Multiple test suites, consisting of multiple tests, can be run on each device in each device pool. The ‘main’ app must include a call to enableFlutterDriverExtension().

Device pools can consist of multiple devices. Devices in a device pool must be of the same type, iOS or Android.

Note: If running on linux or windows, tests can only be run on Android devices. To run tests on both Android and iOS use a mac CI provider.

Building an iOS debug app

To build a testable iOS app locally, that can run on any real device in the cloud, the following environment variable must be present:

    This is the Developer Portal Team ID. It is of the form ‘ABCDEFGHIJ’.

A check is made before the start of a run to confirm this environment variable is present.

Note: if not running on an iOS pool this environment variable is not required.

Populating a device pool

To add devices to a device pool, pick devices from the list provided by

sylph -d android
sylph -d ios

and add to the appropriate pool type in sylph.yaml. The listed devices are devices currently available on Device Farm.

Configuration Validation

The sylph.yaml is validated to confirm the devices are available on Device Farm and tests are present before starting a run.

If running on an iOS pool, the iOS-related environment variables must be defined.

Configuring Flavors

A reference flavor app can be found in example/flavors. It is taken from and works for android and iOS. It is currently recommended that you follow this pattern when implementing flavors in your app.

To enable testing on a flavor add the following to your sylph.yaml:

flavor: <name of flavor>

Configuring a CI Environment for Sylph

In addition to running from the command line, Sylph also runs in a CI environment.

AWS CLI Credentials for CI

The following AWS CLI credentials are required in a CI environment:


For details on other credentials see:

iOS builds

To build the iOS app, the provisioning profile and certificate must be installed on the CI build machine. To install these dependencies, Fastlane’s match is used. Sylph will detect it is running in a CI environment (using the ‘CI’ environment variable), and will install fastlane and fastlane scripts. The scripts are used to install the dependencies using Fastlane’s match. The iOS build can then complete as normal.

The following environment variables are required by a CI build to use Fastlane match:

    This is the location of the private match repo. It expects an ssh-based url. For example, ssh://
    This is the password that was used to encrypt the git repo’s contents during match setup.

For details on how to setup Match see:

The following are required by sylph in a CI environment to connect to the match host. The match host is running a ssh server that connects to the git server which serves the match repo. This configuration is required so that PUBLISHING_MATCH_CERTIFICATE_REPO will work via ssh:

    This is used to configure the CI’s ssh client to find the match host. For example,
    This is used to configure the CI’s ssh client to find the match host’s ssh port. For example, 22.

As with running from the command line, the following environment variable is also required by Sylph in a CI environment:

    This is the Developer Portal Team ID. It is of the form ‘ABCDEFGHIJ’.

Note: if not running on an iOS pool all iOS-related environment variables are not required.

Sample environment variables for Travis-CI

For example, when Sylph is run on Travis-CI the following environment variables are used:

secret variables

See .travis.yml for running Sylph on Travis-CI.

Note: the Travis-CI build uses pre-configured AWS CLI values in .aws/config.


To upgrade, simply re-issue the install command

$ pub global activate sylph

To check the version of Sylph currently installed:

pub global list

Live demo

To see Sylph in action in a CI environment, a demo of the example app is available.

The log of the live run on mac and linux is here:

The resulting artifacts are here:
(includes a video of test running on device)

To view a similar run on windows:


When contributing to this repository, please feel free to discuss via issue or pull request.

Issues and pull requests are welcome.

Your feedback is used to guide where development effort is focused. So feel free to create as many issues and pull requests as you want. You should expect a timely and considered response.

Download Details:

Author: mmcc007


#flutter #dart #mobile-apps

What is GEEK

Buddha Community

Runs Flutter integration tests on real devices in cloud

Google's Flutter 1.20 stable announced with new features - Navoki

Flutter Google cross-platform UI framework has released a new version 1.20 stable.

Flutter is Google’s UI framework to make apps for Android, iOS, Web, Windows, Mac, Linux, and Fuchsia OS. Since the last 2 years, the flutter Framework has already achieved popularity among mobile developers to develop Android and iOS apps. In the last few releases, Flutter also added the support of making web applications and desktop applications.

Last month they introduced the support of the Linux desktop app that can be distributed through Canonical Snap Store(Snapcraft), this enables the developers to publish there Linux desktop app for their users and publish on Snap Store.  If you want to learn how to Publish Flutter Desktop app in Snap Store that here is the tutorial.

Flutter 1.20 Framework is built on Google’s made Dart programming language that is a cross-platform language providing native performance, new UI widgets, and other more features for the developer usage.

Here are the few key points of this release:

Performance improvements for Flutter and Dart

In this release, they have got multiple performance improvements in the Dart language itself. A new improvement is to reduce the app size in the release versions of the app. Another performance improvement is to reduce junk in the display of app animation by using the warm-up phase.


If your app is junk information during the first run then the Skia Shading Language shader provides for pre-compilation as part of your app’s build. This can speed it up by more than 2x.

Added a better support of mouse cursors for web and desktop flutter app,. Now many widgets will show cursor on top of them or you can specify the type of supported cursor you want.

Autofill for mobile text fields

Autofill was already supported in native applications now its been added to the Flutter SDK. Now prefilled information stored by your OS can be used for autofill in the application. This feature will be available soon on the flutter web.


A new widget for interaction

InteractiveViewer is a new widget design for common interactions in your app like pan, zoom drag and drop for resizing the widget. Informations on this you can check more on this API documentation where you can try this widget on the DartPad. In this release, drag-drop has more features added like you can know precisely where the drop happened and get the position.

Updated Material Slider, RangeSlider, TimePicker, and DatePicker

In this new release, there are many pre-existing widgets that were updated to match the latest material guidelines, these updates include better interaction with Slider and RangeSliderDatePicker with support for date range and time picker with the new style.


New pubspec.yaml format

Other than these widget updates there is some update within the project also like in pubspec.yaml file format. If you are a flutter plugin publisher then your old pubspec.yaml  is no longer supported to publish a plugin as the older format does not specify for which platform plugin you are making. All existing plugin will continue to work with flutter apps but you should make a plugin update as soon as possible.

Preview of embedded Dart DevTools in Visual Studio Code

Visual Studio code flutter extension got an update in this release. You get a preview of new features where you can analyze that Dev tools in your coding workspace. Enable this feature in your vs code by _dart.previewEmbeddedDevTools_setting. Dart DevTools menu you can choose your favorite page embed on your code workspace.

Network tracking

The updated the Dev tools comes with the network page that enables network profiling. You can track the timings and other information like status and content type of your** network calls** within your app. You can also monitor gRPC traffic.

Generate type-safe platform channels for platform interop

Pigeon is a command-line tool that will generate types of safe platform channels without adding additional dependencies. With this instead of manually matching method strings on platform channel and serializing arguments, you can invoke native class and pass nonprimitive data objects by directly calling the Dartmethod.

There is still a long list of updates in the new version of Flutter 1.2 that we cannot cover in this blog. You can get more details you can visit the official site to know more. Also, you can subscribe to the Navoki newsletter to get updates on these features and upcoming new updates and lessons. In upcoming new versions, we might see more new features and improvements.

You can get more free Flutter tutorials you can follow these courses:

#dart #developers #flutter #app developed #dart devtools in visual studio code #firebase local emulator suite in flutter #flutter autofill #flutter date picker #flutter desktop linux app build and publish on snapcraft store #flutter pigeon #flutter range slider #flutter slider #flutter time picker #flutter tutorial #flutter widget #google flutter #linux #navoki #pubspec format #setup flutter desktop on windows

Adaline  Kulas

Adaline Kulas


Multi-cloud Spending: 8 Tips To Lower Cost

A multi-cloud approach is nothing but leveraging two or more cloud platforms for meeting the various business requirements of an enterprise. The multi-cloud IT environment incorporates different clouds from multiple vendors and negates the dependence on a single public cloud service provider. Thus enterprises can choose specific services from multiple public clouds and reap the benefits of each.

Given its affordability and agility, most enterprises opt for a multi-cloud approach in cloud computing now. A 2018 survey on the public cloud services market points out that 81% of the respondents use services from two or more providers. Subsequently, the cloud computing services market has reported incredible growth in recent times. The worldwide public cloud services market is all set to reach $500 billion in the next four years, according to IDC.

By choosing multi-cloud solutions strategically, enterprises can optimize the benefits of cloud computing and aim for some key competitive advantages. They can avoid the lengthy and cumbersome processes involved in buying, installing and testing high-priced systems. The IaaS and PaaS solutions have become a windfall for the enterprise’s budget as it does not incur huge up-front capital expenditure.

However, cost optimization is still a challenge while facilitating a multi-cloud environment and a large number of enterprises end up overpaying with or without realizing it. The below-mentioned tips would help you ensure the money is spent wisely on cloud computing services.

  • Deactivate underused or unattached resources

Most organizations tend to get wrong with simple things which turn out to be the root cause for needless spending and resource wastage. The first step to cost optimization in your cloud strategy is to identify underutilized resources that you have been paying for.

Enterprises often continue to pay for resources that have been purchased earlier but are no longer useful. Identifying such unused and unattached resources and deactivating it on a regular basis brings you one step closer to cost optimization. If needed, you can deploy automated cloud management tools that are largely helpful in providing the analytics needed to optimize the cloud spending and cut costs on an ongoing basis.

  • Figure out idle instances

Another key cost optimization strategy is to identify the idle computing instances and consolidate them into fewer instances. An idle computing instance may require a CPU utilization level of 1-5%, but you may be billed by the service provider for 100% for the same instance.

Every enterprise will have such non-production instances that constitute unnecessary storage space and lead to overpaying. Re-evaluating your resource allocations regularly and removing unnecessary storage may help you save money significantly. Resource allocation is not only a matter of CPU and memory but also it is linked to the storage, network, and various other factors.

  • Deploy monitoring mechanisms

The key to efficient cost reduction in cloud computing technology lies in proactive monitoring. A comprehensive view of the cloud usage helps enterprises to monitor and minimize unnecessary spending. You can make use of various mechanisms for monitoring computing demand.

For instance, you can use a heatmap to understand the highs and lows in computing visually. This heat map indicates the start and stop times which in turn lead to reduced costs. You can also deploy automated tools that help organizations to schedule instances to start and stop. By following a heatmap, you can understand whether it is safe to shut down servers on holidays or weekends.

#cloud computing services #all #hybrid cloud #cloud #multi-cloud strategy #cloud spend #multi-cloud spending #multi cloud adoption #why multi cloud #multi cloud trends #multi cloud companies #multi cloud research #multi cloud market

Terry  Tremblay

Terry Tremblay


What is Flutter and why you should learn it?

Flutter is an open-source UI toolkit for mobile developers, so they can use it to build native-looking** Android and iOS** applications from the same code base for both platforms. Flutter is also working to make Flutter apps for Web, PWA (progressive Web-App) and Desktop platform (Windows,macOS,Linux).


Flutter was officially released in December 2018. Since then, it has gone a much stronger flutter community.

There has been much increase in flutter developers, flutter packages, youtube tutorials, blogs, flutter examples apps, official and private events, and more. Flutter is now on top software repos based and trending on GitHub.

Flutter meaning?

What is Flutter? this question comes to many new developer’s mind.


Flutter means flying wings quickly, and lightly but obviously, this doesn’t apply in our SDK.

So Flutter was one of the companies that were acquired by **Google **for around $40 million. That company was based on providing gesture detection and recognition from a standard webcam. But later when the Flutter was going to release in alpha version for developer it’s name was Sky, but since Google already owned Flutter name, so they rename it to Flutter.

Where Flutter is used?

Flutter is used in many startup companies nowadays, and even some MNCs are also adopting Flutter as a mobile development framework. Many top famous companies are using their apps in Flutter. Some of them here are





Reflectly app

Reflectly app

Abbey Road Studios

Abbey Road Studios

and many more other apps. Mobile development companies also adopted Flutter as a service for their clients. Even I was one of them who developed flutter apps as a freelancer and later as an IT company for mobile apps.

Flutter as a service

#dart #flutter #uncategorized #flutter framework #flutter jobs #flutter language #flutter meaning #flutter meaning in hindi #google flutter #how does flutter work #what is flutter

Adaline  Kulas

Adaline Kulas


What are the benefits of cloud migration? Reasons you should migrate

The moving of applications, databases and other business elements from the local server to the cloud server called cloud migration. This article will deal with migration techniques, requirement and the benefits of cloud migration.

In simple terms, moving from local to the public cloud server is called cloud migration. Gartner says 17.5% revenue growth as promised in cloud migration and also has a forecast for 2022 as shown in the following image.

#cloud computing services #cloud migration #all #cloud #cloud migration strategy #enterprise cloud migration strategy #business benefits of cloud migration #key benefits of cloud migration #benefits of cloud migration #types of cloud migration

Software Testing 101: Regression Tests, Unit Tests, Integration Tests

Automation and segregation can help you build better software
If you write automated tests and deliver them to the customer, he can make sure the software is working properly. And, at the end of the day, he paid for it.

Ok. We can segregate or separate the tests according to some criteria. For example, “white box” tests are used to measure the internal quality of the software, in addition to the expected results. They are very useful to know the percentage of lines of code executed, the cyclomatic complexity and several other software metrics. Unit tests are white box tests.

#testing #software testing #regression tests #unit tests #integration tests