Move out of Gitlab Wiki

I understand that this change is quite unreadable and hard to review, sorry for forgetting to do atomic commits. This patch does not change too much content wise, it just
* Gets everything from gitlab wiki
* Removes some specific gitlab hacks
* Formats all documentation file names to be in snake case so they look the same way as our code does

1 files changed, 214 insertions, 0 deletions

diff --git a/docs/installation/arch_linux_en.md b/docs/installation/arch_linux_en.md
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+# Installing on Arch Linux
+## Installation
+
+This guide will assume that you have administrative rights, either as root or a user with [sudo permissions](https://wiki.archlinux.org/index.php/Sudo). If you want to run this guide with root, ignore the `sudo` at the beginning of the lines, unless it calls a user like `sudo -Hu pleroma`; in this case, use `su <username> -s $SHELL -c 'command'` instead.
+
+### Required packages
+
+* `postgresql`
+* `elixir`
+* `erlang-unixodbc`
+* `git`
+* `base-devel`
+
+#### Optional packages used in this guide
+
+* `nginx` (preferred, example configs for other reverse proxies can be found in the repo)
+* `certbot` (or any other ACME client for Let’s Encrypt certificates)
+
+### Prepare the system
+
+* First update the system, if not already done:
+
+```shell
+sudo pacman -Syu
+```
+
+* Install some of the above mentioned programs:
+
+```shell
+sudo pacman -S git base-devel elixir erlang-unixodbc
+```
+
+### Install PostgreSQL
+
+[Arch Wiki article](https://wiki.archlinux.org/index.php/PostgreSQL)
+
+* Install the `postgresql` package:
+
+```shell
+sudo pacman -S postgresql
+```
+
+* Initialize the database cluster:
+
+```shell
+sudo -iu postgres initdb -D /var/lib/postgres/data
+```
+
+* Start and enable the `postgresql.service`
+
+```shell
+sudo systemctl enable --now postgresql.service
+```
+
+### Install PleromaBE
+
+* Add a new system user for the Pleroma service:
+
+```shell
+sudo useradd -r -s /bin/false -m -d /var/lib/pleroma -U pleroma
+```
+
+**Note**: To execute a single command as the Pleroma system user, use `sudo -Hu pleroma command`. You can also switch to a shell by using `sudo -Hu pleroma $SHELL`. If you don’t have and want `sudo` on your system, you can use `su` as root user (UID 0) for a single command by using `su -l pleroma -s $SHELL -c 'command'` and `su -l pleroma -s $SHELL` for starting a shell.
+
+* Git clone the PleromaBE repository and make the Pleroma user the owner of the directory:
+
+```shell
+sudo mkdir -p /opt/pleroma
+sudo chown -R pleroma:pleroma /opt/pleroma
+sudo -Hu pleroma git clone https://git.pleroma.social/pleroma/pleroma /opt/pleroma
+```
+
+* Change to the new directory:
+
+```shell
+cd /opt/pleroma
+```
+
+* Install the dependencies for Pleroma and answer with `yes` if it asks you to install `Hex`:
+
+```shell
+sudo -Hu pleroma mix deps.get
+```
+
+* Generate the configuration: `sudo -Hu pleroma mix pleroma.instance gen`
+  * Answer with `yes` if it asks you to install `rebar3`.
+  * This may take some time, because parts of pleroma get compiled first.
+  * After that it will ask you a few questions about your instance and generates a configuration file in `config/generated_config.exs`.
+
+* Check the configuration and if all looks right, rename it, so Pleroma will load it (`prod.secret.exs` for productive instance, `dev.secret.exs` for development instances):
+
+```shell
+mv config/{generated_config.exs,prod.secret.exs}
+```
+
+* The previous command creates also the file `config/setup_db.psql`, with which you can create the database:
+
+```shell
+sudo -Hu postgres psql -f config/setup_db.psql
+```
+
+* Now run the database migration:
+
+```shell
+sudo -Hu pleroma MIX_ENV=prod mix ecto.migrate
+```
+
+* Now you can start Pleroma already
+
+```shell
+sudo -Hu pleroma MIX_ENV=prod mix phx.server
+```
+
+### Finalize installation
+
+If you want to open your newly installed instance to the world, you should run nginx or some other webserver/proxy in front of Pleroma and you should consider to create a systemd service file for Pleroma.
+
+#### Nginx
+
+* Install nginx, if not already done:
+
+```shell
+sudo pacman -S nginx
+```
+
+* Create directories for available and enabled sites:
+
+```shell
+sudo mkdir -p /etc/nginx/sites-{available,enabled}
+```
+
+* Append the following line at the end of the `http` block in `/etc/nginx/nginx.conf`:
+
+```Nginx
+include sites-enabled/*;
+```
+
+* Setup your SSL cert, using your method of choice or certbot. If using certbot, first install it:
+
+```shell
+sudo pacman -S certbot certbot-nginx
+```
+
+and then set it up:
+
+```shell
+sudo mkdir -p /var/lib/letsencrypt/
+sudo certbot certonly --email <your@emailaddress> -d <yourdomain> --standalone
+```
+
+If that doesn’t work, make sure, that nginx is not already running. If it still doesn’t work, try setting up nginx first (change ssl “on” to “off” and try again).
+
+---
+
+* Copy the example nginx configuration and activate it:
+
+```shell
+sudo cp /opt/pleroma/installation/pleroma.nginx /etc/nginx/sites-available/pleroma.nginx
+sudo ln -s /etc/nginx/sites-available/pleroma.nginx /etc/nginx/sites-enabled/pleroma.nginx
+```
+
+* Before starting nginx edit the configuration and change it to your needs (e.g. change servername, change cert paths)
+* Enable and start nginx:
+
+```shell
+sudo systemctl enable --now nginx.service
+```
+
+If you need to renew the certificate in the future, uncomment the relevant location block in the nginx config and run:
+
+```shell
+sudo certbot certonly --email <your@emailaddress> -d <yourdomain> --webroot -w /var/lib/letsencrypt/
+```
+
+#### Other webserver/proxies
+
+You can find example configurations for them in `/opt/pleroma/installation/`.
+
+#### Systemd service
+
+* Copy example service file
+
+```shell
+sudo cp /opt/pleroma/installation/pleroma.service /etc/systemd/system/pleroma.service
+```
+
+* Edit the service file and make sure that all paths fit your installation
+* Enable and start `pleroma.service`:
+
+```shell
+sudo systemctl enable --now pleroma.service
+```
+
+#### Create your first user
+
+If your instance is up and running, you can create your first user with administrative rights with the following task:
+
+```shell
+sudo -Hu pleroma MIX_ENV=prod mix pleroma.user new <username> <your@emailaddress> --admin
+```
+
+#### Further reading
+
+* [Admin tasks](Admin tasks)
+* [Backup your instance](Backup-your-instance)
+* [Configuration tips](General tips for customizing pleroma fe)
+* [Hardening your instance](Hardening-your-instance)
+* [How to activate mediaproxy](How-to-activate-mediaproxy)
+* [Small Pleroma-FE customizations](Small customizations)
+* [Updating your instance](Updating-your-instance)
+
+## Questions
+
+Questions about the installation or didn’t it work as it should be, ask in [#pleroma:matrix.org](https://matrix.heldscal.la/#/room/#freenode_#pleroma:matrix.org) or IRC Channel **#pleroma** on **Freenode**.