• CovCheck is a WebApp implemented in Haskell

• CovCheck provides real time informations about the current situation of COVID-19 Worldwide
• CovCheck enables an automatic test (Quiz) to check whether someones is infected by the Corona Virus or not.

• WebApp Tutorial
• Postman
• GUI Programming
• App example for Quiz

• Example
• Yesod

• HTTP/2 more features than HTTP/1.x Tutorial
• Postman REST client Tool for Visualization.

Which one?

• Two-tier /var/folders/v0/1hcm36tj5bzfsr_cxj6th8d40000gn/T/TemporaryItems/(A Document Being Saved By screencaptureui)/Screenshot 2020-06-27 at 01.55.41.png
• Three-tier ( + Database Application )

• Apache, Installation Tutorial
• Salvia

• JSON parsing with Aeson
• Warp Server library(for HTTP/1.x and HTTP/2 based Web Application inferface (WAI))

• Cabal
• Postman (covid tracking)

Luca: Database connection, Lidia: backend, Kevin: Client Server Technologie.

1. If you haven't already, install Stack
   • On POSIX systems, this is usually curl -sSL https://get.haskellstack.org/ | sh
2. Install the yesod command line tool: stack install yesod-bin --install-ghc
3. Build libraries: stack build

If you have trouble, refer to the Yesod Quickstart guide for additional detail.

Start a development server with:

stack exec -- yesod devel

As your code changes, your site will be automatically recompiled and redeployed to localhost.

stack test --flag CovCheck:library-only --flag CovCheck:dev

(Because yesod devel passes the library-only and dev flags, matching those flags means you don't need to recompile between tests and development, and it disables optimization to speed up your test compile times).

• Read the Yesod Book online for free
• Check Stackage for documentation on the packages in your LTS Haskell version, or search it using Hoogle. Tip: Your LTS version is in your stack.yaml file.
• For local documentation, use:
  • stack haddock --open to generate Haddock documentation for your dependencies, and open that documentation in a browser
  • stack hoogle <function, module or type signature> to generate a Hoogle database and search for your query
• The Yesod cookbook has sample code for various needs

• Ask questions on Stack Overflow, using the Yesod or Haskell tags
• Ask the Yesod Google Group
• There are several chatrooms you can ask for help:
  • For IRC, try Freenode#yesod and Freenode#haskell
  • Functional Programming Slack, in the #haskell, #haskell-beginners, or #yesod channels.