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path: root/src/micropub/post.rs
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use crate::database::Storage;
use crate::indieauth::User;
use crate::ApplicationState;
use chrono::prelude::*;
use core::iter::Iterator;
use futures::stream;
use futures::StreamExt;
use http_types::Mime;
use log::{error, warn, info};
use newbase60::num_to_sxg;
use std::convert::TryInto;
use std::str::FromStr;
use tide::prelude::json;
use tide::{Request, Response, Result};

static DEFAULT_CHANNEL_PATH: &str = "/feeds/main";
static DEFAULT_CHANNEL_NAME: &str = "Main feed";
static CONTACTS_CHANNEL_PATH: &str = "/feeds/vcards";
static CONTACTS_CHANNEL_NAME: &str = "My address book";

macro_rules! response {
    ($($code:expr, $json:tt)+) => {
        $(
            Ok(Response::builder($code).body(json!($json)).build())
        )+
    };
}

macro_rules! error_json {
    ($($code:expr, $error:expr, $error_desc:expr)+) => {
        $(
            response!($code, {
                "error": $error,
                "error_description": $error_desc
            })
        )+
    }
}

fn get_folder_from_type(post_type: &str) -> String {
    (match post_type {
        "h-feed" => "feeds/",
        "h-card" => "vcards/",
        "h-event" => "events/",
        "h-food" => "food/",
        _ => "posts/",
    })
    .to_string()
}

pub fn normalize_mf2(mut body: serde_json::Value, user: &User) -> (String, serde_json::Value) {
    // Normalize the MF2 object here.
    let me = &user.me;
    let published: DateTime<FixedOffset>;
    let folder = get_folder_from_type(body["type"][0].as_str().unwrap());
    if let Some(dt) = body["properties"]["published"][0].as_str() {
        // Check if the datetime is parsable.
        match DateTime::parse_from_rfc3339(dt) {
            Ok(dt) => {
                published = dt;
            }
            Err(_) => {
                // Reset the datetime to a proper datetime.
                // Do not attempt to recover the information.
                // Do not pass GO. Do not collect $200.
                let curtime: DateTime<Local> = Local::now();
                body["properties"]["published"] =
                    serde_json::Value::Array(vec![serde_json::Value::String(curtime.to_rfc3339())]);
                published = chrono::DateTime::from(curtime);
            }
        }
    } else {
        // Set the datetime.
        let curtime: DateTime<Local> = Local::now();
        body["properties"]["published"] =
            serde_json::Value::Array(vec![serde_json::Value::String(curtime.to_rfc3339())]);
        published = chrono::DateTime::from(curtime);
    }
    match body["properties"]["uid"][0].as_str() {
        None => {
            let uid = serde_json::Value::String(
                me.join(
                    &(folder.clone()
                        + &num_to_sxg(published.timestamp_millis().try_into().unwrap())),
                )
                .unwrap()
                .to_string(),
            );
            body["properties"]["uid"] = serde_json::Value::Array(vec![uid.clone()]);
            match body["properties"]["url"].as_array_mut() {
                Some(array) => array.push(uid),
                None => body["properties"]["url"] = body["properties"]["uid"].clone(),
            }
        }
        Some(uid_str) => {
            let uid = uid_str.to_string();
            match body["properties"]["url"].as_array_mut() {
                Some(array) => {
                    if !array.iter().any(|i| i.as_str().unwrap_or("") == uid) {
                        array.push(serde_json::Value::String(uid))
                    }
                }
                None => body["properties"]["url"] = body["properties"]["uid"].clone(),
            }
        }
    }
    if let Some(slugs) = body["properties"]["mp-slug"].as_array() {
        let new_urls = slugs
            .iter()
            .map(|i| i.as_str().unwrap_or(""))
            .filter(|i| i != &"")
            .map(|i| me.join(&((&folder).clone() + i)).unwrap().to_string())
            .collect::<Vec<String>>();
        let urls = body["properties"]["url"].as_array_mut().unwrap();
        new_urls.iter().for_each(|i| urls.push(json!(i)));
    }
    let props = body["properties"].as_object_mut().unwrap();
    props.remove("mp-slug");

    if body["properties"]["content"][0].is_string() {
        // Convert the content to HTML using the `markdown` crate
        body["properties"]["content"] = json!([{
            "html": markdown::to_html(body["properties"]["content"][0].as_str().unwrap()),
            "value": body["properties"]["content"][0]
        }])
    }
    if body["properties"]["channel"][0].as_str().is_none() {
        if body["type"][0] == "h-entry" {
            // Set the channel to the main channel...
            let default_channel = me.join(DEFAULT_CHANNEL_PATH).unwrap().to_string();

            body["properties"]["channel"] = json!([default_channel]);
        } else if body["type"][0] == "h-card" {
            let default_channel = me.join(CONTACTS_CHANNEL_PATH).unwrap().to_string();

            body["properties"]["channel"] = json!([default_channel]);
        } else {
            body["properties"]["channel"] = json!([]);
        }
        // TODO: Sort other types of posts into channels too
    }
    body["properties"]["posted-with"] = json!([user.client_id]);
    if body["properties"]["author"][0].as_str().is_none() {
        body["properties"]["author"] = json!([me.as_str()])
    }
    // TODO: maybe highlight #hashtags?
    // Find other processing to do and insert it here
    return (
        body["properties"]["uid"][0].as_str().unwrap().to_string(),
        body,
    );
}

pub async fn new_post<S: Storage>(
    req: Request<ApplicationState<S>>,
    body: serde_json::Value,
) -> Result {
    // First, check for rights.
    let user = req.ext::<User>().unwrap();
    let storage = &req.state().storage;
    if !user.check_scope("create") {
        return error_json!(
            401,
            "invalid_scope",
            "Not enough privileges to post. Try a token with a \"create\" scope instead."
        );
    }
    let (uid, post) = normalize_mf2(body, user);

    // Security check!
    // This software might also be used in a multi-user setting
    // where several users or identities share one Micropub server
    // (maybe a family website or a shitpost sideblog?)
    if !post["properties"]["uid"][0]
            .as_str()
            .unwrap()
            .starts_with(user.me.as_str())
        || post["properties"]["channel"]
            .as_array()
            .unwrap()
            .iter()
            .any(|url| !url.as_str().unwrap().starts_with(user.me.as_str()))
    {
        return error_json!(
            403,
            "forbidden",
            "You're trying to post to someone else's website..."
        );
    }

    match storage.post_exists(&uid).await {
        Ok(exists) => {
            if exists {
                return error_json!(
                    409,
                    "already_exists",
                    format!(
                        "A post with the exact same UID already exists in the database: {}",
                        uid
                    )
                );
            }
        }
        Err(err) => return Ok(err.into()),
    }

    if let Err(err) = storage.put_post(&post, user.me.as_str()).await {
        return error_json!(500, "database_error", format!("{}", err));
    }

    // It makes sense to use a loop here, because you wouldn't post to a hundred channels at once
    // Mostly one or two, and even those ones will be the ones picked for you by software
    for channel in post["properties"]["channel"]
        .as_array()
        .unwrap()
        .iter()
        .map(|i| i.as_str().unwrap_or("").to_string())
        .filter(|i| !i.is_empty())
        .collect::<Vec<_>>()
    {
        let default_channel = user.me.join(DEFAULT_CHANNEL_PATH).unwrap().to_string();
        let vcards_channel = user.me.join(CONTACTS_CHANNEL_PATH).unwrap().to_string();
        match storage.post_exists(&channel).await {
            Ok(exists) => {
                if exists {
                    if let Err(err) = storage
                        .update_post(
                            &channel,
                            json!({
                                "add": {
                                    "children": [uid]
                                }
                            }),
                        )
                        .await
                    {
                        return error_json!(
                            500,
                            "database_error",
                            format!(
                                "Couldn't insert post into the channel due to a database error: {}",
                                err
                            )
                        );
                    }
                } else if channel == default_channel || channel == vcards_channel {
                    if let Err(err) = create_feed(storage, &uid, &channel, &user).await {
                        return error_json!(
                            500,
                            "database_error",
                            format!("Couldn't save feed: {}", err)
                        );
                    }
                } else {
                    warn!(
                        "Ignoring request to post to a non-existent feed: {}",
                        channel
                    );
                }
            }
            Err(err) => return error_json!(500, "database_error", err),
        }
    }
    // END WRITE BOUNDARY

    // do background processing on the post
    async_std::task::spawn(post_process_new_post(req, post));

    Ok(Response::builder(202)
        .header("Location", &uid)
        .body(json!({"status": "accepted", "location": &uid}))
        .build())
}

async fn create_feed(
    storage: &impl Storage,
    uid: &str,
    channel: &str,
    user: &User,
) -> crate::database::Result<()> {
    let path = url::Url::parse(channel).unwrap().path().to_string();
    let (name, slug) = if path == DEFAULT_CHANNEL_PATH {
        (DEFAULT_CHANNEL_NAME, "main")
    } else if path == CONTACTS_CHANNEL_PATH {
        (CONTACTS_CHANNEL_NAME, "vcards")
    } else {
        panic!("Tried to create an unknown default feed!");
    };

    let (_, feed) = normalize_mf2(
        json!({
            "type": ["h-feed"],
            "properties": {
                "name": [name],
                "mp-slug": [slug],
            },
            "children": [uid]
        }),
        &user,
    );
    storage.put_post(&feed, user.me.as_str()).await
}

async fn post_process_new_post<S: Storage>(
    req: Request<ApplicationState<S>>,
    post: serde_json::Value,
) {
    // TODO: Post-processing the post (aka second write pass)
    // - [-] Download rich reply contexts
    // - [-] Syndicate the post if requested, add links to the syndicated copies
    // - [ ] Send WebSub notifications to the hub (if we happen to have one)
    // - [x] Send webmentions
    let http = &req.state().http_client;
    let uid = post["properties"]["uid"][0].as_str().unwrap().to_string();
    // 1. Download rich reply contexts
    //    This needs to be done first, because at this step we can also determine webmention endpoints
    //    and save them for later use. Additionally, the richer our content is, the better.
    //    This needs to be done asynchronously, so the posting experience for the author will be as fast
    //    as possible without making them wait for potentially slow downstream websites to load
    // 1.1. Collect the list of contextually-significant post to load context from.
    //      This will include reply-tos, liked, reposted and bookmarked content
    //
    //      TODO: Fetch links mentioned in a post, since we need to send webmentions to those as mentions
    let mut contextually_significant_posts: Vec<surf::Url> = vec![];
    for prop in &["in-reply-to", "like-of", "repost-of", "bookmark-of"] {
        if let Some(array) = post["properties"][prop].as_array() {
            contextually_significant_posts.extend(
                array
                    .iter()
                    .filter_map(|v| v.as_str().and_then(|v| surf::Url::parse(v).ok())),
            );
        }
    }
    // 1.2. Deduplicate the list
    contextually_significant_posts.sort_unstable();
    contextually_significant_posts.dedup();

    // 1.3. Fetch the posts with their bodies and save them in a new Vec<(surf::Url, String)>
    let posts_with_bodies: Vec<(surf::Url, surf::Response, String)> =
        stream::iter(contextually_significant_posts.into_iter())
            .filter_map(|v: surf::Url| async move {
                if let Ok(res) = http.get(&v).send().await {
                    if res.status() != 200 {
                        None
                    } else {
                        Some((v, res))
                    }
                } else {
                    None
                }
            })
            .filter_map(|(v, mut res): (surf::Url, surf::Response)| async move {
                if let Ok(body) = res.body_string().await {
                    Some((v, res, body))
                } else {
                    None
                }
            })
            .collect()
            .await;
    // 1.4. Parse the bodies and include them in relevant places on the MF2 struct
    //      This requires an MF2 parser, and there are none for Rust at the moment.
    //
    // TODO: integrate https://gitlab.com/vikanezrimaya/mf2-parser when it's ready

    // 2. Syndicate the post
    let syndicated_copies: Vec<serde_json::Value>;
    if let Some(syndication_targets) = post["properties"]["syndicate-to"].as_array() {
        syndicated_copies = stream::iter(
            syndication_targets
                .iter()
                .filter_map(|v| v.as_str())
                .filter_map(|t| surf::Url::parse(t).ok())
                .collect::<Vec<_>>()
                .into_iter()
                .map(|_t: surf::Url| async move {
                    // TODO: Define supported syndication methods
                    // and syndicate the endpoint there
                    // Possible ideas:
                    //  - indieweb.xyz (might need a lot of space for the buttons though, investigate proposing grouping syndication targets)
                    //  - news.indieweb.org (IndieNews - needs a category linking to #indienews)
                    //  - Twitter via brid.gy (do I really need Twitter syndication tho?)
                    if false {
                        Some("")
                    } else {
                        None
                    }
                }),
        )
        .buffer_unordered(3)
        .filter_map(|v| async move { v })
        .map(|v| serde_json::Value::String(v.to_string()))
        .collect::<Vec<_>>()
        .await;
    } else {
        syndicated_copies = vec![]
    }
    // Save the post a second time here after syndication
    // We use update_post here to prevent race conditions since its required to be atomic
    let mut update = json!({
        "action": "update",
        "url": &uid
    });
    if !syndicated_copies.is_empty() {
        update["add"] = json!({});
        update["add"]["syndication"] = serde_json::Value::Array(syndicated_copies);
    }
    if !posts_with_bodies.is_empty() {
        error!("Replacing context links with parsed MF2-JSON data is not yet implemented (but it's ok! it'll just be less pretty)")
        /* TODO: Replace context links with parsed MF2-JSON data * /
        update["replace"] = {}
        update["replace"]["like-of"] = []
        update["replace"]["in-reply-to"] = []
        update["replace"]["bookmark-of"] = []
        update["replace"]["repost-of"] = []
        // */
    }
    // We don't need the original copy of the post anymore... I hope!
    // This will act as a safeguard so I can't read stale data by accident anymore...
    drop(post);
    if let Err(err) = req.state().storage.update_post(&uid, update).await {
        error!("Encountered error while post-processing a post: {}", err)
        // At this point, we can still continue, we just won't have rich data for the post
        // I wonder why could it even happen except in case of a database disconnection?
    }
    // 3. Send WebSub notifications
    // TODO WebSub support

    // 4. Send webmentions
    //    We'll need the bodies here to get their endpoints
    let source = &uid;
    stream::iter(posts_with_bodies.into_iter())
        .filter_map(|(url, response, body): (surf::Url, surf::Response, String)| async move {
            // Check Link headers first
            // the first webmention endpoint will be returned
            if let Some(values) = response.header("Link") {
                let mut iter = values.iter().flat_map(|i| i.as_str().split(','));

                for link in iter {
                    let mut split = link.split(";");

                    match split.next() {
                        Some(uri) => {
                            if let Some(uri) = uri.strip_prefix('<') {
                                if let Some(uri) = uri.strip_suffix('>') {
                                    for prop in split {
                                        let lowercased = prop.to_ascii_lowercase();
                                        if &lowercased == "rel=\"webmention\"" || &lowercased == "rel=webmention" {
                                            if let Ok(endpoint) = url.join(uri) {
                                                return Some((url, endpoint));
                                            }
                                        }
                                    }
                                }
                            }
                        },
                        None => continue
                    }
                }
            }
            // TODO: Replace this function once the MF2 parser is ready
            // A compliant parser's output format includes rels,
            // we could just find a Webmention one in there
            let pattern = easy_scraper::Pattern::new(r#"<link href="{url}" rel="webmention">"#)
                .expect("Pattern for webmentions couldn't be parsed");
            let matches = pattern.matches(&body);
            if matches.is_empty() {
                return None;
            }
            let endpoint = &matches[0]["url"];
            if let Ok(endpoint) = url.join(endpoint) {
                Some((url, endpoint))
            } else {
                None
            }
        })
        .map(|(target, endpoint)| async move {
            info!("Sending webmention to {} about {}", source, &target.to_string());
            let response = http
                .post(&endpoint)
                .content_type("application/x-www-form-urlencoded")
                .body(
                    serde_urlencoded::to_string(vec![
                        ("source", source),
                        ("target", &target.to_string()),
                    ])
                    .expect("Couldn't construct webmention form"),
                )
                .send()
                .await;
            match response {
                Ok(response) => {
                    if response.status() == 200
                        || response.status() == 201
                        || response.status() == 202
                    {
                        Ok(())
                    } else {
                        error!(
                            "Sending webmention for {} to {} failed: Endpoint replied with HTTP {}",
                            target,
                            endpoint,
                            response.status()
                        );
                        Err(())
                    }
                }
                Err(err) => {
                    error!(
                        "Sending webmention for {} to {} failed: {}",
                        target, endpoint, err
                    );
                    Err(())
                }
            }
        })
        .buffer_unordered(3)
        .collect::<Vec<_>>()
        .await;
}

async fn process_json<S: Storage>(
    req: Request<ApplicationState<S>>,
    body: serde_json::Value,
) -> Result {
    let is_action = body["action"].is_string() && body["url"].is_string();
    if is_action {
        // This could be an update, a deletion or an undeletion request.
        // Process it separately.
        let action = body["action"].as_str().unwrap();
        let url = body["url"].as_str().unwrap();
        let user = req.ext::<User>().unwrap();
        match action {
            "delete" => {
                if !user.check_scope("delete") {
                    return error_json!(
                        401,
                        "insufficient_scope",
                        "You need a `delete` scope to delete posts."
                    );
                }
                // This special scope is not available through a token endpoint, since the
                // authorization endpoint is supposed to reject any auth request trying to get this
                // scope. It is intended for TRUSTED external services that need to modify the
                // database while ignoring any access controls
                if (url::Url::parse(url)?.origin().ascii_serialization() + "/") != user.me.as_str() && !user.check_scope("kittybox_internal:do_what_thou_wilt") {
                    return error_json!(
                        403,
                        "forbidden",
                        "You're not allowed to delete someone else's posts."
                    )
                }
                if let Err(error) = req.state().storage.delete_post(&url).await {
                    return Ok(error.into());
                }
                Ok(Response::builder(200).build())
            }
            "update" => {
                if !user.check_scope("update") {
                    return error_json!(
                        401,
                        "insufficient_scope",
                        "You need an `update` scope to update posts."
                    );
                }
                if (url::Url::parse(url)?.origin().ascii_serialization() + "/") != user.me.as_str() && !user.check_scope("kittybox_internal:do_what_thou_wilt") {
                    return error_json!(
                        403,
                        "forbidden",
                        "You're not allowed to delete someone else's posts."
                    )
                }
                if let Err(error) = req.state().storage.update_post(&url, body.clone()).await {
                    Ok(error.into())
                } else {
                    Ok(Response::builder(204).build())
                }
            }
            _ => return error_json!(400, "invalid_request", "This action is not supported."),
        }
    } else if body["type"][0].is_string() {
        // This is definitely an h-entry or something similar. Check if it has properties?
        if body["properties"].is_object() {
            // Ok, this is definitely a new h-entry. Let's save it.
            return new_post(req, body).await;
        } else {
            return error_json!(
                400,
                "invalid_request",
                "This MF2-JSON object has a type, but not properties. This makes no sense to post."
            );
        }
    } else {
        return error_json!(
            400,
            "invalid_request",
            "Try sending MF2-structured data or an object with an \"action\" and \"url\" keys."
        );
    }
}

fn convert_form_to_mf2_json(form: Vec<(String, String)>) -> serde_json::Value {
    let mut mf2 = json!({"type": [], "properties": {}});
    for (k, v) in form {
        if k == "h" {
            mf2["type"]
                .as_array_mut()
                .unwrap()
                .push(json!("h-".to_string() + &v));
        } else if k != "access_token" {
            let key = k.strip_suffix("[]").unwrap_or(&k);
            match mf2["properties"][key].as_array_mut() {
                Some(prop) => prop.push(json!(v)),
                None => mf2["properties"][key] = json!([v]),
            }
        }
    }
    if mf2["type"].as_array().unwrap().is_empty() {
        mf2["type"].as_array_mut().unwrap().push(json!("h-entry"));
    }
    mf2
}

async fn process_form<S: Storage>(
    req: Request<ApplicationState<S>>,
    form: Vec<(String, String)>,
) -> Result {
    if let Some((_, v)) = form.iter().find(|(k, _)| k == "action") {
        if v == "delete" {
            let user = req.ext::<User>().unwrap();
            if !user.check_scope("delete") {
                return error_json!(
                    401,
                    "insufficient_scope",
                    "You cannot delete posts without a `delete` scope."
                );
            }
            match form.iter().find(|(k, _)| k == "url") {
                Some((_, url)) => {
                    if (url::Url::parse(url)?.origin().ascii_serialization() + "/") != user.me.as_str() && !user.check_scope("kittybox_internal:do_what_thou_wilt") {
                        return error_json!(
                            403,
                            "forbidden",
                            "You're not allowed to delete someone else's posts."
                        )
                    }
                    if let Err(error) = req.state().storage.delete_post(&url).await {
                        return error_json!(500, "database_error", error);
                    }
                    return Ok(Response::builder(200).build());
                }
                None => {
                    return error_json!(
                        400,
                        "invalid_request",
                        "Please provide an `url` to delete."
                    )
                }
            }
        } else {
            return error_json!(400, "invalid_request", "This action is not supported in form-encoded mode. (JSON requests support more actions, use JSON!)");
        }
    }

    let mf2 = convert_form_to_mf2_json(form);

    if mf2["properties"].as_object().unwrap().keys().len() > 0 {
        return new_post(req, mf2).await;
    }
    return error_json!(
        400,
        "invalid_request",
        "Try sending h=entry&content=something%20interesting"
    );
}

pub async fn post_handler<S: Storage>(mut req: Request<ApplicationState<S>>) -> Result {
    match req.content_type() {
        Some(value) => {
            if value == Mime::from_str("application/json").unwrap() {
                match req.body_json::<serde_json::Value>().await {
                    Ok(parsed) => return process_json(req, parsed).await,
                    Err(err) => {
                        return error_json!(
                            400,
                            "invalid_request",
                            format!("Parsing JSON failed: {:?}", err)
                        )
                    }
                }
            } else if value == Mime::from_str("application/x-www-form-urlencoded").unwrap() {
                match req.body_form::<Vec<(String, String)>>().await {
                    Ok(parsed) => return process_form(req, parsed).await,
                    Err(err) => {
                        return error_json!(
                            400,
                            "invalid_request",
                            format!("Parsing form failed: {:?}", err)
                        )
                    }
                }
            } else {
                return error_json!(
                    415, "unsupported_media_type",
                    "What's this? Try sending JSON instead. (urlencoded form also works but is less cute)"
                );
            }
        }
        _ => {
            return error_json!(
                415, "unsupported_media_type",
                "You didn't send a Content-Type header, so we don't know how to parse your request."
            );
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_no_replace_uid() {
        let mf2 = json!({
            "type": ["h-card"],
            "properties": {
                "uid": ["https://fireburn.ru/"],
                "name": ["Vika Nezrimaya"],
                "note": ["A crazy programmer girl who wants some hugs"]
            }
        });

        let (uid, normalized) = normalize_mf2(
            mf2.clone(),
            &User::new(
                "https://fireburn.ru/",
                "https://quill.p3k.io/",
                "create update media",
            ),
        );
        assert_eq!(
            normalized["properties"]["uid"][0], mf2["properties"]["uid"][0],
            "UID was replaced"
        );
        assert_eq!(
            normalized["properties"]["uid"][0], uid,
            "Returned post location doesn't match UID"
        );
    }

    #[test]
    fn test_form_to_mf2() {
        use serde_urlencoded::from_str;

        assert_eq!(
            convert_form_to_mf2_json(from_str("h=entry&content=something%20interesting").unwrap()),
            json!({
                "type": ["h-entry"],
                "properties": {
                    "content": ["something interesting"]
                }
            })
        )
    }

    #[test]
    fn test_normalize_mf2() {
        let mf2 = json!({
            "type": ["h-entry"],
            "properties": {
                "content": ["This is content!"]
            }
        });

        let (uid, post) = normalize_mf2(
            mf2,
            &User::new(
                "https://fireburn.ru/",
                "https://quill.p3k.io/",
                "create update media",
            ),
        );
        assert_eq!(
            post["properties"]["published"]
                .as_array()
                .expect("post['published'] is undefined")
                .len(),
            1,
            "Post doesn't have a published time"
        );
        DateTime::parse_from_rfc3339(post["properties"]["published"][0].as_str().unwrap())
            .expect("Couldn't parse date from rfc3339");
        assert!(
            post["properties"]["url"]
                .as_array()
                .expect("post['url'] is undefined")
                .len()
                > 0,
            "Post doesn't have any URLs"
        );
        assert_eq!(
            post["properties"]["uid"]
                .as_array()
                .expect("post['uid'] is undefined")
                .len(),
            1,
            "Post doesn't have a single UID"
        );
        assert_eq!(
            post["properties"]["uid"][0], uid,
            "UID of a post and its supposed location don't match"
        );
        assert!(
            uid.starts_with("https://fireburn.ru/posts/"),
            "The post namespace is incorrect"
        );
        assert_eq!(
            post["properties"]["content"][0]["html"]
                .as_str()
                .expect("Post doesn't have a rich content object")
                .trim(),
            "<p>This is content!</p>",
            "Parsed Markdown content doesn't match expected HTML"
        );
        assert_eq!(
            post["properties"]["channel"][0], "https://fireburn.ru/feeds/main",
            "Post isn't posted to the main channel"
        );
        assert_eq!(
            post["properties"]["author"][0], "https://fireburn.ru/",
            "Post author is unknown"
        );
    }

    #[test]
    fn test_mp_slug() {
        let mf2 = json!({
            "type": ["h-entry"],
            "properties": {
                "content": ["This is content!"],
                "mp-slug": ["hello-post"]
            },
        });

        let (_, post) = normalize_mf2(
            mf2,
            &User::new(
                "https://fireburn.ru/",
                "https://quill.p3k.io/",
                "create update media",
            ),
        );
        assert!(
            post["properties"]["url"]
                .as_array()
                .unwrap()
                .iter()
                .map(|i| i.as_str().unwrap())
                .any(|i| i == "https://fireburn.ru/posts/hello-post"),
            "Didn't found an URL pointing to the location expected by the mp-slug semantics"
        );
        assert!(
            post["properties"]["mp-slug"].as_array().is_none(),
            "mp-slug wasn't deleted from the array!"
        )
    }

    #[test]
    fn test_normalize_feed() {
        let mf2 = json!({
            "type": ["h-feed"],
            "properties": {
                "name": "Main feed",
                "mp-slug": ["main"]
            }
        });

        let (uid, post) = normalize_mf2(
            mf2,
            &User::new(
                "https://fireburn.ru/",
                "https://quill.p3k.io/",
                "create update media",
            ),
        );
        assert_eq!(
            post["properties"]["uid"][0], uid,
            "UID of a post and its supposed location don't match"
        );
        assert_eq!(post["properties"]["author"][0], "https://fireburn.ru/");
        assert!(
            post["properties"]["url"]
                .as_array()
                .unwrap()
                .iter()
                .map(|i| i.as_str().unwrap())
                .any(|i| i == "https://fireburn.ru/feeds/main"),
            "Didn't found an URL pointing to the location expected by the mp-slug semantics"
        );
        assert!(
            post["properties"]["mp-slug"].as_array().is_none(),
            "mp-slug wasn't deleted from the array!"
        )
    }
}