Running Syncthing on a VPS

2023-05-30T00:00:00+00:00

I've been going down the self-hosting rabbit hole recently and decided to try out Syncthing</a> as a way of syncing notes across my devices. I decided to run a node on a VPS so that I would have one node running 24/7 that my devices can sync to. This guide will help you set up Syncthing on a VPS and secure it using ufw</a> and fail2ban</a>. This guide will only use the command line (no web GUI).

Installing</h2>

The installation process varies depending on which OS you are running on the server but most common Linux distros should have a version of Syncthing packaged in the default repositories. We are also going to install fail2ban</code> for security.

For Ubuntu or Debian server:

$</span> sudo apt install syncthing fail2ban</span></span></code></pre>
For Arch:</p>
$</span> sudo pacman</span> -S</span> syncthing ufw fail2ban</span></span></code></pre>
For Fedora:</p>
$</span> sudo dnf install syncthing ufw fail2ban</span></span></code></pre>Security</h2>
Disclaimer</h3>
I am not a security expert. Do your own research before following these instructions.</p>
Enable fail2ban</code></h3>
All you have to do to enable fail2ban is run</p>
$</span> systemctl enable fail2ban</span></span>
$</span> systemctl start fail2ban</span></span></code></pre>Opening ports on VPS</h3>
The ports we are going to need open for Syncthing are 22000 and 21027/udp. Your VPS provider should have instructions on opening ports.</p>
Setting up ufw</code></h3>
ufw</code> (uncomplicated firewall) is an easy-to-use firewall tool that we will use to drop all incoming traffic on ports other than the Syncthing ports. We can allow traffic on Syncthing ports by running</p>
$</span> sudo ufw allow syncthing</span></span></code></pre>
If you are using SSH to access your VPS it is also important that your open the SSH port so you don't get locked out. To do this, run sudo ufw allow ssh</code>.</p>
Configuration</h2>
To generate a Syncthing config on the server, run</p>
$</span> syncthing generate</span></span></code></pre>
This should output a device ID, make sure to save this for later. I will refer to this as SERVER_ID</code> from now on.</p>
Connecting a device</h3>
These next instructions will show you how to connect a device, such as a laptop or desktop computer, to the server. First, make sure Syncthing is running on both the device and the server. Start Syncthing on the server by running the following two commands:</p>
$</span> systemctl enable syncthing@USER.service</span></span>
$</span> systemctl start syncthing@USER.service</span></span></code></pre>
where USER</code> is replaced by your username.</p>
First, we will need the device ID of the device. Run syncthing -device-id</code> to get it. I will refer to this as LOCAL_ID</code> from now on. On your local device, run</p>
$</span> syncthing cli config devices add</span> --device-id</span> LOCAL_ID</span></span></code></pre>
and on your local device run</p>
$</span> syncthing cli config devices add</span> --device-id</span> SERVER_ID</span></span></code></pre>
To configure the server to auto-accept folders from the local device, run the following command on the server:</p>
$</span> syncthing cli config devices LOCAL_ID auto-accept-folders set</span> true</span></span></code></pre>
Now you can add a folder from your local device. On the local device, run</p>
$</span> syncthing cli config folders list</span></span></code></pre>
and copy the folder ID of the folder you want to add. Then run</p>
$</span> syncthing cli config folders FOLDER_ID devices add</span> --device-id</span> SERVER_ID</span></span></code></pre>
to add the folder.</p>
Credits</h2>

Thanks to jonny-exe</a> for creating this gist</a>.</li>
This superuser post</a> was also great.</li>
</ul>

Connecting Heroku Postgres to Rust

2022-05-18T00:00:00+00:00

I was learning Postgres and Actix Web recently to create a comment system for this blog and it ended up being a huge pain to connect the Heroku Postgres database to my Actix Web application. Inspired by that pain, I have written this guide.

Dependencies</h1>
This is going to require a few crates. Here is a list of dependencies in `Cargo.toml</code>:`
`[dependencies] url = "2.2.2" tokio-postgres = "0.7.6" deadpool-postgres = "0.10.2" postgres-openssl = "0.5.0" openssl = "0.10.40"</code></pre> Here's what all these dependencies do:`

`url</code>: Used to parse database info from the URL given by Heroku.</li>`
`tokio-postgres</code>: An async client for Postgres in Rust.</li>`
`deadpool-postgres</code>: Async pool for database connections.</li>`
`postgres-openssl</code>: SSL support for Postgres.</li>`
`openssl</code>: SSL support for Rust.</li> </ul> You'll also need some sort of async runtime. For my project I was using Actix Web which runs on Tokio but for simplicity I'm just going to use Tokio for this post.`
`tokio = { version = "1.18.2", features = ["full"] }</code></pre> Now that we have our dependencies added, we're ready to go! Connecting to Postgres</h1>`
Generating a `deadpool_postgres</code> config</h2> When you create a Postgres database in Heroku, it will set an environment variable in your project called DATABASE_URL</code>. Unfortunately we can't use this URL directly so we are going to parse it. Here's what the function to parse it looks like:`
fn config_from_url(url: &str) -> Result<deadpool_postgres::Config, &'static str> { // Config URL is in format: // postgres://USER:PASSWORD@HOST:PORT/DBNAME let url = Url::parse(url).map_err(|_| "could not parse db url")?; let user = url.username().to_string(); let password = url.password().ok_or("bad password")?.to_string(); let host = url.host().ok_or("bad host")?.to_string(); let port = url.port().ok_or("no port in url")?; let dbname = url .path_segments() .ok_or("cannot be base")? .next() .unwrap() .to_string(); let mut cfg = deadpool_postgres::Config::new(); cfg.user = Some(user); cfg.password = Some(password); cfg.host = Some(host); cfg.port = Some(port); cfg.dbname = Some(dbname); Ok(cfg) }</code></pre> Let's give it a try! #[tokio::main] async fn main() { let database_url = std::env::var("DATABASE_URL").unwrap(); let cfg = config_from_url(&database_url).unwrap(); dbg!(&cfg); }</code></pre> The output you get should look something like this: [src/main.rs:35] &cfg = Config { user: Some( "[user]", ), password: Some( "[password]", ), dbname: Some( "[database name]", ), options: None, application_name: None, ssl_mode: None, host: Some( "[link]", ), hosts: None, port: Some( [port], ), ports: None, connect_timeout: None, keepalives: None, keepalives_idle: None, target_session_attrs: None, channel_binding: None, manager: None, pool: None, }</code></pre> With all the values in the square brackets being replaced by the values from the Heroku URL. Setting up SSL</h2> This was the biggest headache for me but it's actually very simple. The thing with Heroku Postgres is that it requires SSL, but doesn't give certificates. To make this work we need to set the SSL verify mode to off in our SSL config in Rust. let mut builder = SslConnector::builder(SslMethod::tls()).unwrap(); builder.set_verify(SslVerifyMode::NONE); let connector = MakeTlsConnector::new(builder.build());</code></pre> And that's all the SSL stuff we need to do. Creating a connection pool</h2> Creating a connection pool with deadpool_postgres</code> is just one line of code: let pool = cfg.create_pool(None, connector).unwrap();</code></pre> And that's it for the setup! Now we can query the database. Querying the database</h1> Creating a table</h2> Before we can query anything we need to create a table in our database. If you have already done this just skip to the next step. I'm going to make a directory for all our SQL files in the root of the project. The structure should now look like this: . ├── .gitignore ├── Cargo.lock ├── Cargo.toml ├── sql └── src └── main.rs</code></pre> For creating the table I'll make a file called schema.sql</code> in the sql directory. For this example we'll make a simple blog system. We will store the id, author, date, title, and content of each post. The SQL code to create such a table looks like this: CREATE TABLE post ( id SERIAL PRIMARY KEY, posted DATE NOT NULL DEFAULT CURRENT_DATE, author VARCHAR(50) NOT NULL, title VARCHAR(255) NOT NULL, content TEXT NOT NULL );</code></pre> We can write a function in our Rust code to call this SQL query. // Add this at the top of your file use deadpool_postgres::Client; async fn create_table(client: &Client) { let stmt = include_str!("../sql/schema.sql"); let stmt = client.prepare(stmt).await.unwrap(); client.query(&stmt, &[]).await.unwrap(); }</code></pre> I'm just going to put this at the bottom of my main function, run it once, then remove it. You could also use the psql command line tool instead of all of this if you prefer. Inserting some data</h2> Now lets make another SQL file to add a post. I'll call it add_post.sql</code>. INSERT INTO post (author, title, content) VALUES ($1, $2, $3);</code></pre> We omit the date field because Postgres will default it to the current date. The numbers prefixed by $ will be replaced in our Rust code. Now lets make a struct to represent one post. struct Post { author: String, title: String, content: String, }</code></pre> Now that we have the SQL to add a post and the Rust struct, we can write a function that inserts a Post</code> into the database. async fn add_post(client: &Client, post: Post) { let stmt = include_str!("../sql/add_post.sql"); let stmt = client.prepare(stmt).await.unwrap(); let res = client .query(&stmt, &[&post.author, &post.title, &post.content]) .await .unwrap(); dbg!(res); }</code></pre>Getting data</h2> Getting data is very similar to inserting data. Say we want to get all the posts where the author is "John Doe". First we need to build an SQL query. I'll make a file called get_posts.sql</code>. SELECT * FROM post WHERE author=$1 ORDER BY posted DESC;</code></pre> Now we make a Rust function very similar to the one used to add a new post: async fn get_posts(client: &Client, author: &str) { let stmt = include_str!("../sql/get_posts.sql"); let stmt = client.prepare(stmt).await.unwrap(); let res = client .query(&stmt, &[&author]) .await .unwrap(); dbg!(res); }</code></pre>Conclusion</h1> These are the basic building blocks you need to use Heroku Postgres from Rust. Hopefully this was helpful! Please leave a comment if something in this post needs to be clarified. If you plan to use any of this code you should DEFINITELY add error handling instead of just unwrapping everything! If you want to see the project that I used this in, check out this old commit of my website</a>. I actually ended up getting rid of the backend in a later commit and switching to a different comment system but the code works fine.

Security</h2>

Disclaimer</h3>
I am not a security expert. Do your own research before following these instructions.</p>

Opening ports on VPS</h3>
The ports we are going to need open for Syncthing are 22000 and 21027/udp. Your VPS provider should have instructions on opening ports.</p>

Credits</h2>

Thanks to jonny-exe</a> for creating this gist</a>.</li>
This superuser post</a> was also great.</li> </ul>

Connecting to Postgres</h1>

Querying the database</h1>

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Running Syncthing on a VPS

Connecting Heroku Postgres to Rust

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How to Setup Cloudflare Email Routing with Gmail (receive + send)

Running Syncthing on a VPS

Security</h2>

Disclaimer</h3> I am not a security expert. Do your own research before following these instructions.</p>

Opening ports on VPS</h3> The ports we are going to need open for Syncthing are 22000 and 21027/udp. Your VPS provider should have instructions on opening ports.</p>

Credits</h2> Thanks to jonny-exe</a> for creating this gist</a>.</li> This superuser post</a> was also great.</li> </ul>

Connecting Heroku Postgres to Rust

Dependencies</h1> This is going to require a few crates. Here is a list of dependencies in Cargo.toml</code>:</p>

Connecting to Postgres</h1>

Querying the database</h1>

Disclaimer</h3>
I am not a security expert. Do your own research before following these instructions.</p>

Opening ports on VPS</h3>
The ports we are going to need open for Syncthing are 22000 and 21027/udp. Your VPS provider should have instructions on opening ports.</p>

Credits</h2>

Thanks to jonny-exe</a> for creating this gist</a>.</li>
This superuser post</a> was also great.</li> </ul>