lemmy/server/src/lib.rs

#![recursion_limit = "512"]
#[macro_use]
pub extern crate strum_macros;
#[macro_use]
pub extern crate lazy_static;
#[macro_use]
pub extern crate failure;
pub extern crate actix;
pub extern crate actix_web;
pub extern crate bcrypt;
pub extern crate chrono;
pub extern crate diesel;
pub extern crate dotenv;
pub extern crate jsonwebtoken;
extern crate log;
pub extern crate openssl;
pub extern crate rss;
pub extern crate serde;
pub extern crate serde_json;
pub extern crate sha2;
pub extern crate strum;

pub mod api;
pub mod apub;
pub mod code_migrations;
pub mod rate_limit;
pub mod request;
pub mod routes;
pub mod version;
pub mod websocket;

use crate::request::{retry, RecvError};
use actix_web::{client::Client, dev::ConnectionInfo};
use log::error;
use percent_encoding::{utf8_percent_encode, NON_ALPHANUMERIC};
use serde::Deserialize;

pub type DbPool = diesel::r2d2::Pool<diesel::r2d2::ConnectionManager<diesel::PgConnection>>;
pub type ConnectionId = usize;
pub type PostId = i32;
pub type CommunityId = i32;
pub type UserId = i32;
pub type IPAddr = String;

#[derive(Debug)]
pub struct LemmyError {
  inner: failure::Error,
}

impl<T> From<T> for LemmyError
where
  T: Into<failure::Error>,
{
  fn from(t: T) -> Self {
    LemmyError { inner: t.into() }
  }
}

impl std::fmt::Display for LemmyError {
  fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
    self.inner.fmt(f)
  }
}

impl actix_web::error::ResponseError for LemmyError {}

#[derive(Deserialize, Debug)]
pub struct IframelyResponse {
  title: Option<String>,
  description: Option<String>,
  thumbnail_url: Option<String>,
  html: Option<String>,
}

pub async fn fetch_iframely(client: &Client, url: &str) -> Result<IframelyResponse, LemmyError> {
  let fetch_url = format!("http://iframely/oembed?url={}", url);

  let mut response = retry(|| client.get(&fetch_url).send()).await?;

  let res: IframelyResponse = response
    .json()
    .await
    .map_err(|e| RecvError(e.to_string()))?;
  Ok(res)
}

#[derive(Deserialize, Debug, Clone)]
pub struct PictrsResponse {
  files: Vec<PictrsFile>,
  msg: String,
}

#[derive(Deserialize, Debug, Clone)]
pub struct PictrsFile {
  file: String,
  delete_token: String,
}

pub async fn fetch_pictrs(client: &Client, image_url: &str) -> Result<PictrsResponse, LemmyError> {
  is_image_content_type(client, image_url).await?;

  let fetch_url = format!(
    "http://pictrs:8080/image/download?url={}",
    utf8_percent_encode(image_url, NON_ALPHANUMERIC) // TODO this might not be needed
  );

  let mut response = retry(|| client.get(&fetch_url).send()).await?;

  let response: PictrsResponse = response
    .json()
    .await
    .map_err(|e| RecvError(e.to_string()))?;

  if response.msg == "ok" {
    Ok(response)
  } else {
    Err(format_err!("{}", &response.msg).into())
  }
}

async fn fetch_iframely_and_pictrs_data(
  client: &Client,
  url: Option<String>,
) -> (
  Option<String>,
  Option<String>,
  Option<String>,
  Option<String>,
) {
  match &url {
    Some(url) => {
      // Fetch iframely data
      let (iframely_title, iframely_description, iframely_thumbnail_url, iframely_html) =
        match fetch_iframely(client, url).await {
          Ok(res) => (res.title, res.description, res.thumbnail_url, res.html),
          Err(e) => {
            error!("iframely err: {}", e);
            (None, None, None, None)
          }
        };

      // Fetch pictrs thumbnail
      let pictrs_thumbnail = match iframely_thumbnail_url {
        Some(iframely_thumbnail_url) => match fetch_pictrs(client, &iframely_thumbnail_url).await {
          Ok(res) => Some(res.files[0].file.to_owned()),
          Err(e) => {
            error!("pictrs err: {}", e);
            None
          }
        },
        // Try to generate a small thumbnail if iframely is not supported
        None => match fetch_pictrs(client, &url).await {
          Ok(res) => Some(res.files[0].file.to_owned()),
          Err(e) => {
            error!("pictrs err: {}", e);
            None
          }
        },
      };

      (
        iframely_title,
        iframely_description,
        iframely_html,
        pictrs_thumbnail,
      )
    }
    None => (None, None, None, None),
  }
}

pub async fn is_image_content_type(client: &Client, test: &str) -> Result<(), LemmyError> {
  let response = retry(|| client.get(test).send()).await?;

  if response
    .headers()
    .get("Content-Type")
    .ok_or_else(|| format_err!("No Content-Type header"))?
    .to_str()?
    .starts_with("image/")
  {
    Ok(())
  } else {
    Err(format_err!("Not an image type.").into())
  }
}

pub fn get_ip(conn_info: &ConnectionInfo) -> String {
  conn_info
    .realip_remote_addr()
    .unwrap_or("127.0.0.1:12345")
    .split(':')
    .next()
    .unwrap_or("127.0.0.1")
    .to_string()
}

pub async fn blocking<F, T>(pool: &DbPool, f: F) -> Result<T, LemmyError>
where
  F: FnOnce(&diesel::PgConnection) -> T + Send + 'static,
  T: Send + 'static,
{
  let pool = pool.clone();
  let res = actix_web::web::block(move || {
    let conn = pool.get()?;
    let res = (f)(&conn);
    Ok(res) as Result<_, LemmyError>
  })
  .await?;

  Ok(res)
}

#[cfg(test)]
mod tests {
  use crate::is_image_content_type;

  #[test]
  fn test_image() {
    actix_rt::System::new("tset_image").block_on(async move {
      let client = actix_web::client::Client::default();
      assert!(is_image_content_type(&client, "https://1734811051.rsc.cdn77.org/data/images/full/365645/as-virus-kills-navajos-in-their-homes-tribal-women-provide-lifeline.jpg?w=600?w=650").await.is_ok());
      assert!(is_image_content_type(&client,
                                    "https://twitter.com/BenjaminNorton/status/1259922424272957440?s=20"
      )
        .await.is_err()
      );
    });
  }

  // These helped with testing
  // #[test]
  // fn test_iframely() {
  //   let res = fetch_iframely(client, "https://www.redspark.nu/?p=15341").await;
  //   assert!(res.is_ok());
  // }

  // #[test]
  // fn test_pictshare() {
  //   let res = fetch_pictshare("https://upload.wikimedia.org/wikipedia/en/2/27/The_Mandalorian_logo.jpg");
  //   assert!(res.is_ok());
  //   let res_other = fetch_pictshare("https://upload.wikimedia.org/wikipedia/en/2/27/The_Mandalorian_logo.jpgaoeu");
  //   assert!(res_other.is_err());
  // }
}