Huge improvements for docs (#58)

docs/content/doc/development/structure.md

@@ -0,0 +1,136 @@
+---
+date: "2019-02-12:00:00+02:00"
+title: "Project structure"
+draft: false
+type: "doc"
+menu:
+  sidebar:
+    parent: "development"
+---
+
+# Project structure
+
+In general, this api repo has the following structure:
+
+* `docker`
+* `docs`
+* `pkg`
+  * `caldav`
+  * `config`
+  * `log`
+  * `mail`
+  * `metrics`
+  * `models`
+  * `red`
+  * `routes`
+    * `api/v1`
+  * `swagger`
+  * `utils`
+* `REST-Tests`
+* `templates`
+* `vendor`
+
+This document will explain what these mean and what you can find where.
+
+## Root level
+
+The root directory is where [the config file]({{< ref "../setup/config.md">}}), [Makefile]({{< ref "make.md">}}), license, drone config, 
+application entry point (`main.go`) and so on are located.
+
+## docker
+
+This directory holds additonal files needed to build and run the docker container, mainly service configuration to properly run Vikunja inside a docker 
+container.
+
+## pkg
+
+This is where most of the magic happens. Most packages with actual code are located in this folder.
+
+### caldav
+
+This folder holds a simple caldav implementation which is responsible for returning the caldav feature.
+
+### config
+
+This package configures the config. It sets default values and sets up viper and tells it where to look for config files, 
+how to interpret which env variables for config etc.
+
+If you want to add a new config parameter, you should add default value in this package.
+
+### log
+
+Similar to `config`, this will set up the logging, based on differen logging backends.
+This init is called in `main.go` after the config init is done.
+
+### mail
+
+This package handles all mail sending. To learn how to send a mail, see [sending emails]({{< ref "../practical-instructions/mail.md">}}).
+
+### metrics
+
+This package handles all metrics which are exposed to the prometheus endpoint.
+To learn how it works and how to add new metrics, take a look at [how metrics work]({{< ref "../practical-instructions/metrics.md">}}).
+
+### models
+
+This is where most of the magic happens.
+When adding new features or upgrading existing ones, that most likely happens here.
+
+Because this package is pretty huge, there are several documents and how-to's about it:
+
+* [Adding a feature]({{< ref "../practical-instructions/feature.md">}})
+* [Making calls to the database]({{< ref "../practical-instructions/database.md">}})
+
+### red (redis)
+
+This package initializes a connection to a redis server.
+This inizialization is automatically done at the startup of vikunja.
+
+It also has a function (`GetRedis()`) which returns a redis client object you can then use in your package 
+to talk to redis.
+
+It uses the [go-redis](https://github.com/go-redis/redis) library, please see their configuration on how to use it.
+
+### routes
+
+This package defines all routes which are available for vikunja clients to use.
+To add a new route, see [adding a new route]({{< ref "../practical-instructions/feature.md">}}).
+
+#### api/v1
+
+This is where all http-handler functions for the api are stored. 
+Every handler function which does not use the standard web handler should live here.
+
+### swagger
+
+This is where the [generated]({{< ref "make.md#generate-swagger-definitions-from-code-comments">}} [api docs]({{< ref "../usage/api.md">}}) live. 
+You usually don't need to touch this package.
+
+### utils
+
+A small package, containing some helper functions:
+
+* `MakeRandomString`: Generates a random string of a given length.
+* `Sha256`: Calculates a sha256 hash from a given string.
+
+See their function definitions for instructions on how to use them. 
+
+## REST-Tests
+
+Holds all kinds of test files to directly test the api from inside of [jetbrains ide's](https://www.jetbrains.com/help/idea/http-client-in-product-code-editor.html).
+
+These files are currently more an experiment, maybe we will drop them in the future to use something we could integrate in the testing process with drone.
+Therefore, this has no claim to be complete yet even working, you're free to change whatever is needed to get it working for you.
+
+## templates
+
+Holds the email templates used to send plain text and html emails for new user registration and password changes.
+
+## vendor
+
+All libraries needed to build Vikunja. 
+
+We keep all libraries used for Vikunja around in the `vendor/` folder to still be able to build the project even if
+some maintainers take their libraries down like [it happened in the past](https://github.com/jteeuwen/go-bindata/issues/5).
+
+When adding a new  dependency, make sure to run `go mod vendor` to put it inside this directory.