Web scraper and RSS feed generator with Spring Boot

Rich Site Summary (RSS) is not quite state-of-art technology but thanks to its simplicity RSS feeds are still useful nowadays.

In this post I’ll show you how you can parse websites and provide your own RSS feed with Spring Boot and few useful libraries such as JSoup and ROME.

Please note: This post isn’t a step-by-step tutorial. The source code with fully working example can be found on GitHub.

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Run performance test on your endpoints with JMeter

Recently I was testing and comparing cloud functions services. For this purpose the JMeter was chosen to provide simple single endpoint test. Today I’d like to share the whole process with you. It’s really easy, so let’s go through it.

In this short tutorial you’ll learn how to use JMeter to run simple performance test for single web service endpoint (or a website) using HTTP/HTTPS requests and generate the test report.

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Send push notifications from Spring Boot server-side application using FCM

As you probably noticed, I familiarize myself with the subject of Firebase Cloud Messaging push notifications recently.

This time I would like to share with you my push notifications server-side application. The app is made with the Spring Boot framework.

The provided example covers most common notifications sending use cases such as: sending push notification to a topic, directly to the users’ device, or sending messages with additional data payload.

This post is not a step-by-step tutorial. I’ll focus on the most important parts. A fully working example is available on GitHub.

If you don’t have a client-side application to receive push notifications yet, you should consider the use of the Ionic app I described earlier. Have fun!

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Get DynamoDB items from AWS Lambda function

Recently I was using DynamoDB with AWS Lambda functions and in this post I would like to share with you few recipes for querying DynamoDB tables from AWS Lambda Node.js function.

In this short post I’ll show you how to get single item and all the items from the database. Former uses query function and the latter will use scan function.

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Send FCM push notifications with AWS Lambda function

Push notifications are back here again. In this case I’m going to send it from the clouds.

In this simple example I’ll use AWS Lambda function with API Gateway integration and Firebase Cloud Messaging service in order to send push notifications to the topic subscribers.

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Send test FCM push notification with Amazon SNS

If you’d like to test your Firebase push notifications service or you’re considering to use another push notifications service provider you should take a look at Amazon Simple Notification Service.  You can use Amazon SNS for sending example push notifications via Firebase Cloud Messaging to your mobile application.

In this short example I’ll show you how you can send a message to a specific user of your Android application. So far I couldn’t find a solution to send messages to Firebase topics subscribers but at least you don’t have to deal with OAuth tokens.

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Get your simple push notifications app with Ionic 4 and Firebase Cloud Messaging

Recently I needed a simple mobile app to test my simple push notifications service. In my case, it was an Android app receiving notifications from Firebase Cloud Messaging.

In this article, I’m going to share my experience with you. I’ll show you how you can create your own simple Ionic 4 Android app and integrate it with the FCM service.

But first of all, I’m going to start with disclaimers:

  • Please remember that this is only a simple starter example. To make sure your notifications behaving properly you have to store user subscriptions somewhere (for example in Firebase or local storage).
  • This article doesn’t cover the iOS platform but it’s possible to use FCM as your push notifications provider in iOS apps.

Main goals

We’d like our app to have the following features:

  • store devices tokens in the Firebase database
  • overall push notifications receiving
  • topic-based push notifications subscription / subscription

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Send your test FCM push notification with cURL

Authorization needed to send push notifications with FCM is cool and not so complicated to integrate on your server app. Take a look at documentation here.

Quicker way

Server app? Great, but sometimes you have to quickly test your FCM push notifications and not necessarily you want create a whole back-end infrastructure just to send some notifications out.

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What map engine choose when Google Maps crashed? 3 best alternatives

This page can’t load Google Maps correctly” or “For development purposes only“…
Sound familiar to you?

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OpenWeatherMap – best weather data API for your projects

Recently Weather Underground announced that they’re no longer supporting their free API plans.

I really liked WUnderground and used it in several projects, but if you’re relaying on external services you have to remember that your API provider can change. So don’t tie yourself with specific solution.

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