Add superlinter

This PR includes updates needed to make the linting pass.

Closes #133

.github/workflows/pr.yml

@@ -0,0 +1,31 @@
+name: PR
+
+on: pull_request
+
+concurrency:
+  group: pr-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  superlinter:
+    name: Lint bash, docker, markdown, and yaml
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Lint codebase
+        uses: docker://github/super-linter:v3.8.3
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          VALIDATE_ALL_CODEBASE: true
+          VALIDATE_BASH: true
+          VALIDATE_DOCKERFILE: true
+          VALIDATE_MD: true
+          VALIDATE_YAML: true
+
+  validate-docker-image-builds:
+    name: Validate Docker image builds
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Docker build
+        run: "docker build --pull docker/."

INSTALL.md

@@ -2,7 +2,7 @@
 
 ## From Ubuntu 18.04
 
-```
+```bash
 # let's update first
 sudo apt-get update
 
@@ -29,7 +29,7 @@ See https://docs.docker.com/engine/install/ubuntu/
 
 It boils down to:
 
-```
+```bash
 # cleanup old stuff
 sudo apt-get remove docker docker-engine docker.io containerd runc
 
@@ -49,15 +49,15 @@ sudo apt-get install -y docker-ce docker-ce-cli containerd.io
 
 ### Webserver setup
 
-```
+```bash
 add-apt-repository ppa:certbot/certbot
 apt-get update
 apt-get install -y nginx python-certbot-nginx
 ```
 
 Create /etc/nginx/sites-enabled/playground.ponylang.io.conf
 
-```
+```text
 server {
     listen 80 default_server;
     listen [::]:80 default_server;
@@ -70,7 +70,7 @@ server {
 }
 ```
 
-```
+```bash
 rm /etc/nginx/sites-enabled/default
 ln -sf /etc/nginx/sites-available/playground.ponylang.io.conf /etc/nginx/sites-enabled/playground.ponylang.io.conf
 
@@ -79,27 +79,27 @@ nginx -t && nginx -s reload
 
 ### SSL setup
 
-```
+```bash
 certbot --nginx -d playground.ponylang.io -m [email protected]
 ```
 
 crontab -e
 
-```
+```text
 0 12 * * * /usr/bin/certbot renew --quiet
 05 12 * * * systemctl restart playground
 ```
 
 ### Start docker
 
-```
+```bash
 systemctl enable docker
 systemctl start docker
 ```
 
 ### Install rust
 
-```
+```bash
 curl https://sh.rustup.rs | sh
 ```
 
@@ -108,15 +108,15 @@ select `1` from prompt
 
 As this file might be outdated, make sure the version here corresponds to the version listed in the `rust-toolchain` file of this repo.
 
-```
+```bash
 source /root/.profile
 rustup install 1.60.0
 rustup default 1.60.0
 ```
 
 ### Build playground image
 
-```
+```bash
 git clone https://github.com/ponylang/pony-playground.git
 cd pony-playground
 docker build docker --pull -t ponylang-playpen
@@ -131,15 +131,15 @@ Should ONLY be the token, not "user:token"
 
 ### Build it
 
-```
+```bash
 cargo build --release --bin playpen
 ```
 
 ### Create Systemd Unit
 
 Put the following in the file `/etc/systemd/system/playground.service`, put in the generated GITHUB_TOKEN from above:
 
-```
+```text
 [Unit]
 Description=Pony Playground Systemd Service Unit
 Requires=docker.service
@@ -156,14 +156,14 @@ WantedBy=multi-user.target
 
 ### Enable and Run it
 
-```
+```bash
 systemctl enable playground
 systemctl start playground
 ```
 
 STDOUT and STDERR both go the journal. If you want to investigate logs, use:
 
-```
+```bash
 journalctl -u playground ...
 ```