library

Introducing Coinpaprika and announcing C# API Client

Introducing Coinpaprika and announcing C# API Client

As I am diving deeper and deeper into the world of cryptocurrencies, I am exploring quite some interesting products. One of them is Coinpaprika, a market research site with some extensive information on every coin they have listed.

What is Coinpaprika?

In the world of cryptocurrencies, there are several things one needs to discover before investing. Starting with information on the project and its digital currencies, the persons behind a project as well as their current value and its price, there is a lot of data to walk through before investing. Several sites out there are providing aggregated information, and even provide APIs for us developers. However, most of them are

  •  extremely rate limited
  •  freemium with a complex pricing model
  •  slow

Why Coinpaprika?

A lot of services that provide aggregated data rely on data of the big players like CoinMarketCap. Coinpaprika, however, has a different strategy. They are pulling their data from a whopping number of 176 exchanges into their own databases, without any proxy. They have their own valuation system and a very fast refreshing rate (16 000 price updates per minute). If you have some time and want to compare how prices match up with their competition, Coinpaprika even implemented a metrics page for you. In my personal experience, their data is more reliable average to those values I see on those exchanges I deal with (Binance, Coinbase, BitPanda, Changelly, Shapeshift).

Coinpaprika API and Clients

Early last week, I discovered Coinpaprika on Steemit. They announced their API is now available to the general public along with clients for PHP, GO, Swift and NodeJS. Coinpaprika has also a WordPress plugin and an embeddable widget (on a coin’s detail page) that allows you to easily show price information on your website. After discovering their site, I got in contact with them to discuss a possible C# implementation for several reasons:

  •  very generous rate limits (25 920 00 requests per month, others are around 6 000 to 10 000), which enables very different implementation scenarios
  •  their API is fast like hell
  •  their independence from third parties besides exchanges
  •  their very catchy name (just being honest)

A few days later, I was able to discuss the publication of the C# API client implementation I wrote with them. I am happy to announce that you can now download the C# API Client from Nuget or fork it from my Github repository. They will also link to it from their official API repository soon. The readme-file on Github serves as documentation as well and shows how to easily integrate their data into your .NET apps. The library itself is written in .NET Standard 2.0. If there is the need to target lower versions, feel free to open a pull request on Github. The Github repo contains also a console tester application.

Conclusion

If you need reliable market data and information on the different projects behind all those cryptocurrencies, you should evaluate Coinpaprika. They aggregate their data without any third party involved and provide an easy to use and blazing fast API. I hope my contribution in form of the C# API client will be helpful for some of you out there.

If you like their product as much as I do, follow them:

  • Twitter: https://twitter.com/coinpaprika
  • Facebook: https://www.facebook.com/coinpaprika/
  • Steemit: https://steemit.com/@coinpaprika
  • Medium: https://medium.com/coinpaprika
  • Telegram: https://t.me/Coinpaprika

Happy coding, everyone!

Posted by msicc in Crypto&Blockchain, Dev Stories, Editorials, 1 comment
WordPressReader (Standard) version 1.2.0 focuses on improving performance

WordPressReader (Standard) version 1.2.0 focuses on improving performance

The update contains several improvements to the HttpClientimplementation, which should improve performance of the library a lot:

  • all handlers now use one static HttpClientinstance. HttpClientis built to use it that way, and there is also no problem with multiple request handled by that instance. So everyone should use it in that way
  • the library is now actively enforcing gzip/deflate compression to make responses faster, especially when requesting bigger lists of items (if you want do deactivate it on the managed implementation, pass in falsewith the new useCompressionparameter with your call to the SetupClientmethod
  • deserialization by default now happens directly from the HttpResponsestream instead of first converting it to a string
  • added an API to pass in your own HttpClientinstance instead of the managed one (you could even use one static instance for your whole app this way to improve performance even further). To do so, just use the newly added method SetCustomClient(HttpClient client)on your handler instances.

I made this changes working without breaking existing implementations. Just by updating the library, you will get a better performance.

I also updated the source code on GitHub. If you just want to update the library, the update is already available on NuGet.

Happy coding, everyone!

P.S.
If you want to see the library in a live app, you can download my official blog reader app (which is written around it as a Xamarin.Formsapp) here:

iOS  Android  Windows 10

Posted by msicc in Dev Stories, 1 comment
WordPressReader (Standard) library is now available on Nuget

WordPressReader (Standard) library is now available on Nuget

I am happy to announce my new WordPressReader (Standard) library that is available on NuGet now. It is written in .netStandard 1.4 which enables you to use it in a lot of of places. As the name suggests, it focuses on reading tasks against the WordPress API.

Features:

  • get, search and filter posts
  • get pages
  • get and filter categories
  • get, search and filter tags
  • get comments
  • post anonymous comments (needs additional work on the WordPress site)
  • get basic user info

The library uses a generic WordPressEntity model implementation, which makes it easy to implement and extend. You can always get the raw json-value as well. The additional Error property on every model makes it easy to handle API errors properly. You can read the full documentation in the GitHub Wiki.

If you have problems with the library or want to contribute, you can do so on the GitHub repo.

Happy coding, everyone!

P.S.
If you want to see the library in a live app, you can download my official blog reader app (which is written around it) here:

iOS  Android  Windows 10

 

Posted by msicc in Dev Stories, 2 comments

How to create a folder in Windows Phone 8.1 Pictures Library (and save/read files into/from it)

Some of you might have noticed that UniShare has its own folder in your devices picture library. Also some other apps like WhatsApp or Tweetium have it. The advantages of your app’s own folder are clear:

  • easier to get images into your app
  • user can always reflect which pictures come from your app
  • another presence of your app within the OS
  • higher remember rate for your app at the user site (which leads to more frequent usage of your app)

This post will show you how easy it is to generate a folder into the Pictures Library as well as save and read files into/from this folder.

Preparation

First, you need to add this using statements to your app:

using Windows.Storage;
using Windows.Storage.Streams;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Media.Imaging;

Next, add the Picture Library capabilities to your app’s Package.appmanifest.

image

If you have a 8.1 Silverlight app, you need to add it to both the Package.appmanifest as well as the WMAppManifest.xml:

image

Then we are already able to generate our folder with this single line of code (counts for both Silverlight and Runtime apps):

StorageFolder appFolder= await KnownFolders.PicturesLibrary.CreateFolderAsync("myCustomAppFolder", CreationCollisionOption.OpenIfExists);

You should always use the CreateFolderAsync method together with the CollisionOption ‘OpenIfExists’. This way, your app will open it every time you are going to save a file, but creates the folder if it does not exist yet. If you now go to your pictures library, you will not see your folder yet, although it is there (use a File Manager app to check it if you want). Folders do only get populated when they have content. This is what the next step is about.

Save an image file

Saving an image is also pretty straight forward. First we are generating a StorageFile within our folder:

StorageFile myfile= await appFolder.CreateFileAsync("myfile.jpg", CreationCollisionOption.ReplaceExisting);

This generates a File Container that we can write our image to. To save the image we are going to asynchronously write the Stream of our image into it:

//asuming we have an Image control, replace this with your local code
var img = myImage.Source as WriteableBitmap;
//get fresh drawn image 
img.Invalidate();

using (Stream stream = await myfile.OpenStreamForWriteAsync())
{
   img.SaveJpeg(stream, img.PixelWidth, img.PixelHeight, 0, 100);
}

This code works for both a Windows Phone 8.1 Silverlight and Runtime apps. If you now go to your Pictures library, you will see your app’s folder as well as your saved image. Pretty easy, right?

Read images from our app’s folder

Reading an image file is pretty easy as well. Here is the code:

//open the picture library
StorageFolder libfolder = KnownFolders.PicturesLibrary;
//get all folders first
IReadOnlyList<StorageFolder> folderList = await libfolder.GetFoldersAsync();
//select our app's folder
var appfolder = folderList.FirstOrDefault(f => f.Name.Contains("myCustomAppFolder"));
//get the desired file (assuming you know the file name)
StorageFile picfile = await appPicturesFolder.GetFileAsync("myfile.jpg");
//generate a stream from the StorageFile
var stream = await picfile.OpenAsync(FileAccessMode.Read);
//generate a new image and set the source to our stream
BitmapImage img = new BitmapImage();
img.SetSource(stream);

//todo: work with the image

To get our generated folder, we need to fetch a list of folders in the library using the StorageFolder.GetFoldersAsync() method. We then query this list for our app’s folder. If you want to get a list of all pictures in your folder, you can use the StorageFile.GetFilesAsync() method. What I have done above is to load our saved single file. Finally, I opened a stream from this file and assigned it to a new BitmapImage, which can be used in our app.

There are also a lot of other options one can do with these folders and files, this is a very common scenario.

As always, I hope this post is helpful for some of you.

Posted by msicc in Dev Stories, windev, 0 comments

WordPressUniversal – a PCL library for WordPress based C# mobile apps

WP_CSharp_Lib

As I have already developed a news reader app for my blog, I got asked quite a few times if I want to share my code to help others creating their apps. As I need to redesign my blog reader to match the latest OS features of Windows and Windows Phone, I decided to create my WordPressUniversal library.

Automattic, the company behind WordPress, integrated a powerful JSON API into their JetPack plugin. My library is based on this API. Please make sure the JSON API is active on the blog you are developing your app for.

The library currently provides the following features:

  • getting a list posts or pages
  • getting a list of all categories
  • getting a list of comments for the site and single posts
  • supports Windows Phone 8 & 8.1 Silverlight, Windows Phone 8.1 RT, Windows 8, Xamarin.iOS and Xamarin.Android

The library deserializes all data into C# objects you can immediately work with.

It is still a work in progress, but as it provides already a bunch of options to get you started, I am making this public already.

I am constantly working on the library, so be sure to follow the project along.

Note: JetPack’s JSON API does not support guest commenting at the moment. I already reached out to Automattic to (hopefully) find a solution for this. If you cannot wait, Disqus has a portable solution for Windows Phone apps.

Please make sure to see the documentation on my GitHub page.

If you have any questions, idea, wishes for me, just post a comment here or ping on Twitter.

Happy coding everyone!

Posted by msicc in Archive, 17 comments