This tool is meant to download and extract recipe information from the German cooking website chefkoch.de. The recipes can be downloaded to either Yaml or JSON format, JSON being the default. Since there basically exists a JSON library for every common programming language this gives a standardized interface to post processing tasks in a programming language agnostic way.
The content of the downloaded recipes consists of the recipe's ingredients list, its cooking instructions and a couple of meta data, e.g. its URL.
The chefkoch tool is written in Haskell and maintained as a stack, cabal and Nix project, stack making use of the cabal build system under the hoods. The cabal configuration files are also provided with this project. It is not a requirement to have Nix installed in order to install this program, it is simply another option available. I use Nix to ensure that my development environment stays stable. The simplest way to acquire stack and cabal is to install the Haskell Platform.
This results in following options to install chefkoch
$ git clone https://github.com/TobiasPleyer/chefkoch
$ cd chefkoch
$ # this requires stack to be installed on the system
$ stack install
$ git clone https://github.com/TobiasPleyer/chefkoch
$ cd chefkoch
$ # the next steps require runhaskell, e.g. via the Haskell Plattform
$ runhaskell Setup configure
$ runhaskell Setup build
$ sudo runhaskell Setup install
$ git clone https://github.com/TobiasPleyer/chefkoch
$ cd chefkoch
$ # the next steps require that Nix has been installed on your system
$ nix-shell
$ # We are now entering the reproducible shell environment provisioned by Nix
[nix-shell]$ cabal build
# lots of output...
Linking /path_to_repo/chefkoch/dist-newstyle/.../chefkoch ...
# ^ The executable is found under this path
# You could leave the Nix shell now if you want...
# As a nice shorthand cabal allows you to run the executable like so
[nix-shell]$ cabal run chefkoch -- --help
# ^ This separates cabal's command line options
# from those of the run program
$ chefkoch --help
chefkoch - a web crawler for the www.chefkoch.de cooking website
Usage: chefkoch [-u|--url URL] [-o|--output FILE] [-f|--format ARG]
[-v|--verbose]
Download the bare ingredients and cooking informations, without all the
clutter.
Available options:
-u,--url URL The url of the recipe to be downloaded.
-o,--output FILE The name of the file to write the output to.
-f,--format ARG Specify the format to be used for output. Supported
values: raw, yaml, json (default).
-v,--verbose Send more info about program execution to stdout.
-h,--help Show this help text
The chefkoch script basically has two operation modes: direct URL or recipe of the day. In URL mode any recipe can be downloaded by providing the URL. This is done via the -u/--url option.
The recipe of the day mode is the default and automatically active if the -u/--url is not given. It can be used to select recipes from the rezept-des-tages listing. This is a data base of featured recipes. Every day one recipe gets featured. The chefkoch script allows you to download the recipe of the current day.
Currently the following output formats are supported:
* json (default)
* yaml
* raw
Per default chefkoch will write all recipe information to standard out. This can be changed with the -o/--output option. With this option you can provide a file name to write the information to.
$ chefkoch --help
$ chefkoch --url https://www.chefkoch.de/rezepte/1113761217428134/Brauhaus-Gulasch.html
$ chefkoch
$ chefkoch -v -f yaml
$ chefkoch --format=yaml -o ./recipe.yaml
What is this nix folder for? This folder contains all Nix related files required to create the (fixed) build environment for the project.
The main purpose of Nix is to provide a stable build environment for me and everyone interested to hack on the tool. I do all my work within a nix-shell environment. Nix will make sure that all required Haskell packages are installed and with versions compatible to each other. In addition the Nix derivation setups up the build and development environment for me. This includes:
- ghc
- ghci
- ghcid
- ghcide
- hlint
Except for ghc these are not necessary to build the project, but are tightly connected to my personal development environment.
If you want to work with Nix in the nix-shell then first install Nix and then run the following command:
$ nix-shell
[nix-shell]$ # We are in the Nix environment now, all tools are on the PATH
This project uses a fixed version of nixpkgs to guarantee reproducability. Currently this version is 19.09. In order to use a different version of nixpkgs you can run this command:
$ nix-prefetch-github --rev '19.09' NixOS nixpkgs > nix/nixpkgs/github.json