Initial commit

.gitignore

@@ -0,0 +1,6 @@
+/target
+crates/*/target
+
+db.json
+config.toml
+schema.sql

Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "rustical"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+rustical_store = { path = "./crates/store/" }
+rustical_api = { path = "./crates/api/" }
+rustical_dav = { path = "./crates/dav/" }
+serde = { version = "1.0.188", features = ["derive"] }
+tokio = { version = "1.32.0", features = [
+  "net",
+  "tracing",
+  "macros",
+  "rt-multi-thread",
+  "full",
+] }
+tracing = "0.1.37"
+env_logger = "0.10.0"
+actix-web = "4.4.0"
+anyhow = { version = "1.0.75", features = ["backtrace"] }
+serde_json = "1.0.105"
+toml = "0.7.6"
+clap = { version = "4.4.2", features = ["derive", "env"] }

README.md

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+# Rustical (WIP)
+
+a calendar server
+

crates/api/Cargo.toml

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+[package]
+name = "rustical_api"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+actix-web = "4.4.0"
+anyhow = { version = "1.0.75", features = ["backtrace"] }
+rustical_store = { path = "../store/" }
+serde = "1.0.188"
+serde_json = "1.0.105"
+tokio = { version = "1.32.0", features = ["sync"] }

crates/api/src/lib.rs

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+use actix_web::{
+    http::Method,
+    web::{self, Data, Path},
+    Responder,
+};
+use rustical_store::calendar::CalendarStore;
+use tokio::sync::RwLock;
+
+pub fn configure_api<C: CalendarStore>(cfg: &mut web::ServiceConfig, store: Data<RwLock<C>>) {
+    cfg.app_data(store)
+        .route("ping", web::method(Method::GET).to(get_ping::<C>))
+        .route(
+            "/{cid}/events",
+            web::method(Method::GET).to(get_events::<C>),
+        );
+}
+
+pub async fn get_events<C: CalendarStore>(
+    store: Data<RwLock<C>>,
+    path: Path<String>,
+) -> impl Responder {
+    let cid = path.into_inner();
+    let events = store.read().await.get_events(&cid).await.unwrap();
+    serde_json::to_string_pretty(&events)
+}
+
+pub async fn get_ping<C: CalendarStore>(store: Data<RwLock<C>>) -> impl Responder {
+    let cals = store.read().await.get_calendars().await.unwrap();
+    serde_json::to_string_pretty(&cals)
+}

crates/dav/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "rustical_dav"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+actix-web = "4.4.0"
+actix-web-httpauth = "0.8.0"
+anyhow = { version = "1.0.75", features = ["backtrace"] }
+base64 = "0.21.3"
+derive_more = "0.99.17"
+futures-util = "0.3.28"
+quick-xml = { version = "0.30.0", features = [
+  "serde",
+  "serde-types",
+  "serialize",
+] }
+roxmltree = "0.18.0"
+rustical_store = { path = "../store/" }
+serde = { version = "1.0.188", features = ["serde_derive", "derive"] }
+serde_json = "1.0.105"
+tokio = { version = "1.32.0", features = ["sync", "full"] }

crates/dav/src/depth_extractor.rs

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+use actix_web::{http::StatusCode, FromRequest, HttpRequest, ResponseError};
+use derive_more::Display;
+use futures_util::future::{err, ok, Ready};
+
+#[derive(Debug, Display)]
+pub struct InvalidDepthHeader {}
+
+impl ResponseError for InvalidDepthHeader {
+    fn status_code(&self) -> actix_web::http::StatusCode {
+        StatusCode::BAD_REQUEST
+    }
+}
+
+#[derive(Debug, PartialEq)]
+pub enum Depth {
+    Zero,
+    One,
+    Infinity,
+}
+
+impl TryFrom<&[u8]> for Depth {
+    type Error = InvalidDepthHeader;
+
+    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
+        match value {
+            b"0" => Ok(Depth::Zero),
+            b"1" => Ok(Depth::One),
+            b"Infinity" | b"infinity" => Ok(Depth::Infinity),
+            _ => Err(InvalidDepthHeader {}),
+        }
+    }
+}
+
+impl FromRequest for Depth {
+    type Error = InvalidDepthHeader;
+    type Future = Ready<Result<Self, Self::Error>>;
+
+    fn extract(req: &HttpRequest) -> Self::Future {
+        if let Some(depth_header) = req.headers().get("Depth") {
+            match depth_header.as_bytes().try_into() {
+                Ok(depth) => ok(depth),
+                Err(e) => err(e),
+            }
+        } else {
+            // default depth
+            ok(Depth::Zero)
+        }
+    }
+
+    fn from_request(req: &HttpRequest, _payload: &mut actix_web::dev::Payload) -> Self::Future {
+        Self::extract(req)
+    }
+}

crates/dav/src/error.rs

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+use actix_web::{http::StatusCode, HttpResponse};
+use derive_more::{Display, Error};
+
+#[derive(Debug, Display, Error)]
+pub enum Error {
+    #[display(fmt = "Internal server error")]
+    InternalError,
+    #[display(fmt = "Not found")]
+    NotFound,
+    #[display(fmt = "Bad request")]
+    BadRequest,
+    Unauthorized,
+}
+
+impl actix_web::error::ResponseError for Error {
+    fn status_code(&self) -> StatusCode {
+        match *self {
+            Self::InternalError => StatusCode::INTERNAL_SERVER_ERROR,
+            Self::NotFound => StatusCode::NOT_FOUND,
+            Self::BadRequest => StatusCode::BAD_REQUEST,
+            Self::Unauthorized => StatusCode::UNAUTHORIZED,
+        }
+    }
+
+    fn error_response(&self) -> HttpResponse {
+        HttpResponse::build(self.status_code()).body(self.to_string())
+    }
+}

crates/dav/src/lib.rs

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+use actix_web::http::Method;
+use actix_web::web::{self, Data};
+use actix_web::{guard, HttpResponse, Responder};
+use actix_web_httpauth::middleware::HttpAuthentication;
+use error::Error;
+use routes::{calendar, event, principal, root};
+use rustical_store::calendar::CalendarStore;
+use std::str::FromStr;
+use tokio::sync::RwLock;
+
+pub mod depth_extractor;
+pub mod error;
+pub mod namespace;
+mod propfind;
+pub mod routes;
+
+pub fn configure_well_known(cfg: &mut web::ServiceConfig, caldav_root: String) {
+    cfg.service(web::redirect("/caldav", caldav_root).permanent());
+}
+
+pub fn configure_dav<C: CalendarStore>(cfg: &mut web::ServiceConfig, store: Data<RwLock<C>>) {
+    let propfind_method = || Method::from_str("PROPFIND").unwrap();
+    let report_method = || Method::from_str("REPORT").unwrap();
+
+    let auth = HttpAuthentication::basic(|req, creds| async move {
+        if creds.user_id().is_empty() {
+            // not authenticated
+            Err((actix_web::error::ErrorUnauthorized("Unauthorized"), req))
+        } else {
+            Ok(req)
+        }
+    });
+
+    cfg.app_data(store)
+        .service(
+            web::resource("{path:.*}")
+                // Without the guard this service would handle all requests
+                .guard(guard::Method(Method::OPTIONS))
+                .to(options_handler),
+        )
+        .service(
+            web::resource("")
+                .route(web::method(propfind_method()).to(root::route_propfind_root))
+                .wrap(auth.clone()),
+        )
+        .service(
+            web::resource("/{principal}")
+                .route(web::method(propfind_method()).to(principal::route_propfind_principal::<C>))
+                .wrap(auth.clone()),
+        )
+        .service(
+            web::resource("/{principal}/{calendar}")
+                .route(web::method(report_method()).to(calendar::route_report_calendar::<C>))
+                .route(web::method(propfind_method()).to(calendar::route_propfind_calendar::<C>))
+                .wrap(auth.clone()),
+        )
+        .service(
+            web::resource("/{principal}/{calendar}/{event}")
+                .route(web::method(Method::DELETE).to(event::delete_event::<C>))
+                .route(web::method(Method::GET).to(event::get_event::<C>))
+                .route(web::method(Method::PUT).to(event::put_event::<C>))
+                .wrap(auth.clone()),
+        );
+}
+
+async fn options_handler() -> impl Responder {
+    HttpResponse::Ok()
+        .insert_header((
+            "Allow",
+            "OPTIONS, GET, HEAD, POST, PUT, REPORT, PROPFIND, PROPPATCH",
+        ))
+        .insert_header((
+            "DAV",
+            "1, 2, 3, calendar-access, extended-mkcol",
+            // "1, 2, 3, calendar-access, addressbook, extended-mkcol",
+        ))
+        .body("options")
+}

crates/dav/src/namespace.rs

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+use quick_xml::events::attributes::Attribute;
+
+// An enum keeping track of the XML namespaces used for WebDAV and its extensions
+//
+// Can also generate appropriate attributes for quick_xml
+pub enum Namespace {
+    Dav,
+    CalDAV,
+    ICal,
+    CServer,
+}
+
+impl Namespace {
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            Self::Dav => "DAV:",
+            Self::CalDAV => "urn:ietf:params:xml:ns:caldav",
+            Self::ICal => "http://apple.com/ns/ical/",
+            Self::CServer => "http://calendarserver.org/ns/",
+        }
+    }
+
+    // Returns an opinionated namespace attribute name
+    pub fn xml_attr(&self) -> &'static str {
+        match self {
+            Self::Dav => "xmlns",
+            Self::CalDAV => "xmlns:C",
+            Self::ICal => "xmlns:IC",
+            Self::CServer => "xmlns:CS",
+        }
+    }
+}
+
+impl From<Namespace> for Attribute<'static> {
+    fn from(value: Namespace) -> Self {
+        (value.xml_attr(), value.as_str()).into()
+    }
+}

crates/dav/src/propfind.rs

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+use actix_web::http::StatusCode;
+use anyhow::{anyhow, Result};
+use quick_xml::{
+    events::{attributes::Attribute, BytesText},
+    Writer,
+};
+
+pub fn parse_propfind(body: &str) -> Result<Vec<&str>> {
+    if body.is_empty() {
+        // if body is empty, allprops must be returned (RFC 4918)
+        return Ok(vec!["allprops"]);
+    }
+    let doc = roxmltree::Document::parse(body)?;
+
+    let propfind_node = doc.root_element();
+    if propfind_node.tag_name().name() != "propfind" {
+        return Err(anyhow!("invalid tag"));
+    }
+
+    let prop_node = if let Some(el) = propfind_node.first_element_child() {
+        el
+    } else {
+        return Ok(Vec::new());
+    };
+
+    match prop_node.tag_name().name() {
+        "prop" => Ok(prop_node
+            .children()
+            .map(|node| node.tag_name().name())
+            .collect()),
+        _ => Err(anyhow!("invalid prop tag")),
+    }
+}
+
+pub fn write_resourcetype(
+    writer: &mut Writer<&mut Vec<u8>>,
+    types: Vec<&str>,
+) -> Result<(), quick_xml::Error> {
+    writer
+        .create_element("resourcetype")
+        .write_inner_content(|writer| {
+            for resourcetype in types {
+                writer.create_element(resourcetype).write_empty()?;
+            }
+            Ok(())
+        })?;
+    Ok(())
+}
+
+pub fn write_invalid_props_response(
+    writer: &mut Writer<&mut Vec<u8>>,
+    href: &str,
+    invalid_props: Vec<&str>,
+) -> Result<(), quick_xml::Error> {
+    if invalid_props.is_empty() {
+        return Ok(());
+    };
+
+    write_propstat_response(writer, href, StatusCode::NOT_FOUND, |writer| {
+        for prop in invalid_props {
+            writer.create_element(prop).write_empty()?;
+        }
+        Ok(())
+    })?;
+
+    Ok(())
+}
+
+// Writes a propstat response into a multistatus
+// closure hooks into the <prop> element
+pub fn write_propstat_response<F>(
+    writer: &mut Writer<&mut Vec<u8>>,
+    href: &str,
+    status: StatusCode,
+    prop_closure: F,
+) -> Result<(), quick_xml::Error>
+where
+    F: FnOnce(&mut Writer<&mut Vec<u8>>) -> Result<(), quick_xml::Error>,
+{
+    writer
+        .create_element("response")
+        .write_inner_content(|writer| {
+            writer
+                .create_element("href")
+                .write_text_content(BytesText::new(href))?;
+
+            writer
+                .create_element("propstat")
+                .write_inner_content(|writer| {
+                    writer
+                        .create_element("prop")
+                        .write_inner_content(prop_closure)?;
+
+                    writer
+                        .create_element("status")
+                        .write_text_content(BytesText::new(&format!("HTTP/1.1 {}", status)))?;
+                    Ok(())
+                })?;
+
+            Ok(())
+        })?;
+    Ok(())
+}
+
+pub fn generate_multistatus<'a, F, A>(namespaces: A, closure: F) -> Result<String>
+where
+    F: FnOnce(&mut Writer<&mut Vec<u8>>) -> Result<(), quick_xml::Error>,
+    A: IntoIterator,
+    A::Item: Into<Attribute<'a>>,
+{
+    let mut output_buffer = Vec::new();
+    let mut writer = Writer::new_with_indent(&mut output_buffer, b' ', 2);
+    writer
+        .create_element("multistatus")
+        .with_attributes(namespaces)
+        .write_inner_content(closure)?;
+
+    Ok(format!(
+        "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n{}",
+        std::str::from_utf8(&output_buffer)?
+    ))
+}

crates/dav/src/routes/calendar.rs

@@ -0,0 +1,207 @@
+use crate::namespace::Namespace;
+use crate::propfind::{
+    generate_multistatus, parse_propfind, write_invalid_props_response, write_propstat_response,
+    write_resourcetype,
+};
+use crate::Error;
+use actix_web::http::header::ContentType;
+use actix_web::http::StatusCode;
+use actix_web::web::{Data, Path};
+use actix_web::{HttpRequest, HttpResponse};
+use actix_web_httpauth::extractors::basic::BasicAuth;
+use anyhow::Result;
+use quick_xml::events::BytesText;
+use quick_xml::Writer;
+use roxmltree::{Node, NodeType};
+use rustical_store::calendar::{Calendar, CalendarStore, Event};
+use std::collections::HashSet;
+use std::ops::Deref;
+use std::sync::Arc;
+use tokio::sync::RwLock;
+
+async fn handle_report_calendar_query(
+    query_node: Node<'_, '_>,
+    request: HttpRequest,
+    events: Vec<Event>,
+) -> Result<HttpResponse, Error> {
+    let prop_node = query_node
+        .children()
+        .find(|n| n.node_type() == NodeType::Element && n.tag_name().name() == "prop")
+        .ok_or(Error::BadRequest)?;
+
+    let props: Arc<HashSet<&str>> = Arc::new(
+        prop_node
+            .children()
+            .map(|node| node.tag_name().name())
+            .collect(),
+    );
+    let output = generate_multistatus(vec![Namespace::Dav, Namespace::CalDAV], |writer| {
+        for event in events {
+            write_propstat_response(
+                writer,
+                &format!("{}/{}", request.path(), event.get_uid()),
+                StatusCode::OK,
+                |writer| {
+                    for prop in props.deref() {
+                        match *prop {
+                            "getetag" => {
+                                writer
+                                    .create_element("getetag")
+                                    .write_text_content(BytesText::new(&event.get_etag()))?;
+                            }
+                            "calendar-data" => {
+                                writer
+                                    .create_element("C:calendar-data")
+                                    .write_text_content(BytesText::new(event.to_ics()))?;
+                            }
+                            _ => {}
+                        }
+                    }
+                    Ok(())
+                },
+            )?;
+        }
+        Ok(())
+    })
+    .map_err(|_e| Error::InternalError)?;
+
+    Ok(HttpResponse::MultiStatus()
+        .content_type(ContentType::xml())
+        .body(output))
+}
+
+pub async fn route_report_calendar<C: CalendarStore>(
+    store: Data<RwLock<C>>,
+    body: String,
+    path: Path<(String, String)>,
+    request: HttpRequest,
+) -> Result<HttpResponse, Error> {
+    let (_principal, cid) = path.into_inner();
+
+    let doc = roxmltree::Document::parse(&body).map_err(|_e| Error::InternalError)?;
+    let query_node = doc.root_element();
+    let events = store.read().await.get_events(&cid).await.unwrap();
+
+    // TODO: implement filtering
+    match query_node.tag_name().name() {
+        "calendar-query" => {}
+        "calendar-multiget" => {}
+        _ => return Err(Error::BadRequest),
+    };
+    handle_report_calendar_query(query_node, request, events).await
+}
+
+pub fn generate_propfind_calendar_response(
+    props: Vec<&str>,
+    principal: &str,
+    path: &str,
+    calendar: &Calendar,
+) -> Result<String> {
+    let mut props = props;
+    if props.contains(&"allprops") {
+        props.extend(
+            [
+                "resourcetype",
+                "current-user-principal",
+                "displayname",
+                "supported-calendar-component-set",
+                "getcontenttype",
+                "calendar-description",
+            ]
+            .iter(),
+        );
+    }
+
+    let mut invalid_props = Vec::<&str>::new();
+    let mut output_buffer = Vec::new();
+    let mut writer = Writer::new_with_indent(&mut output_buffer, b' ', 2);
+
+    write_propstat_response(&mut writer, path, StatusCode::OK, |writer| {
+        for prop in props {
+            match prop {
+                "resourcetype" => write_resourcetype(writer, vec!["C:calendar", "collection"])?,
+                "current-user-principal" => {
+                    writer
+                        .create_element("current-user-principal")
+                        .write_inner_content(|writer| {
+                            writer
+                                .create_element("href")
+                                .write_text_content(BytesText::new(&format!(
+                                    // TODO: Replace hard-coded string
+                                    "/dav/{principal}/",
+                                )))?;
+                            Ok(())
+                        })?;
+                }
+                "displayname" => {
+                    let el = writer.create_element("displayname");
+                    if let Some(name) = calendar.clone().name {
+                        el.write_text_content(BytesText::new(&name))?;
+                    } else {
+                        el.write_empty()?;
+                    }
+                }
+                "supported-calendar-component-set" => {
+                    writer
+                        .create_element("C:supported-calendar-component-set")
+                        .write_inner_content(|writer| {
+                            writer
+                                .create_element("C:comp")
+                                .with_attribute(("name", "VEVENT"))
+                                .write_empty()?;
+                            Ok(())
+                        })?;
+                }
+                "getcontenttype" => {
+                    writer
+                        .create_element("getcontenttype")
+                        .write_text_content(BytesText::new("text/calendar"))?;
+                }
+                "allprops" => {}
+                _ => invalid_props.push(prop),
+            };
+        }
+        Ok(())
+    })?;
+
+    write_invalid_props_response(&mut writer, path, invalid_props)?;
+    Ok(std::str::from_utf8(&output_buffer)?.to_string())
+}
+
+pub async fn route_propfind_calendar<C: CalendarStore>(
+    path: Path<(String, String)>,
+    body: String,
+    request: HttpRequest,
+    auth: BasicAuth,
+    store: Data<RwLock<C>>,
+) -> Result<HttpResponse, Error> {
+    let (_principal, cid) = path.into_inner();
+    let calendar = store
+        .read()
+        .await
+        .get_calendar(&cid)
+        .await
+        .map_err(|_e| Error::InternalError)?;
+
+    let props = parse_propfind(&body).map_err(|_e| Error::BadRequest)?;
+
+    let responses_string = generate_propfind_calendar_response(
+        props.clone(),
+        auth.user_id(),
+        request.path(),
+        &calendar,
+    )
+    .map_err(|_e| Error::InternalError)?;
+
+    let output = generate_multistatus(vec![Namespace::Dav, Namespace::CalDAV], |writer| {
+        writer.write_event(quick_xml::events::Event::Text(BytesText::from_escaped(
+            responses_string,
+        )))?;
+        Ok(())
+    })
+    .map_err(|_e| Error::InternalError)?;
+
+    Ok(HttpResponse::MultiStatus()
+        .content_type(ContentType::xml())
+        .body(output))
+}

crates/dav/src/routes/event.rs

@@ -0,0 +1,64 @@
+use crate::Error;
+use actix_web::web::{Data, Path};
+use actix_web::HttpResponse;
+use rustical_store::calendar::CalendarStore;
+use tokio::sync::RwLock;
+
+pub async fn delete_event<C: CalendarStore>(
+    store: Data<RwLock<C>>,
+    path: Path<(String, String, String)>,
+) -> Result<HttpResponse, Error> {
+    let (_principal, mut cid, uid) = path.into_inner();
+    if cid.ends_with(".ics") {
+        cid.truncate(cid.len() - 4);
+    }
+    store
+        .write()
+        .await
+        .delete_event(&uid)
+        .await
+        .map_err(|_e| Error::InternalError)?;
+
+    Ok(HttpResponse::Ok().body(""))
+}
+
+pub async fn get_event<C: CalendarStore>(
+    store: Data<RwLock<C>>,
+    path: Path<(String, String, String)>,
+) -> Result<HttpResponse, Error> {
+    let (_principal, mut cid, uid) = path.into_inner();
+    if cid.ends_with(".ics") {
+        cid.truncate(cid.len() - 4);
+    }
+    let event = store
+        .read()
+        .await
+        .get_event(&uid)
+        .await
+        .map_err(|_e| Error::NotFound)?;
+
+    Ok(HttpResponse::Ok()
+        .insert_header(("ETag", event.get_etag()))
+        .body(event.to_ics().to_string()))
+}
+
+pub async fn put_event<C: CalendarStore>(
+    store: Data<RwLock<C>>,
+    path: Path<(String, String, String)>,
+    body: String,
+) -> Result<HttpResponse, Error> {
+    let (_principal, mut cid, uid) = path.into_inner();
+    // Incredibly bodged method of normalising the uid but works for a prototype
+    if cid.ends_with(".ics") {
+        cid.truncate(cid.len() - 4);
+    }
+    dbg!(&body);
+    store
+        .write()
+        .await
+        .upsert_event(uid, body)
+        .await
+        .map_err(|_e| Error::InternalError)?;
+
+    Ok(HttpResponse::Ok().body(""))
+}

crates/dav/src/routes/mod.rs

@@ -0,0 +1,4 @@
+pub mod calendar;
+pub mod event;
+pub mod principal;
+pub mod root;

crates/dav/src/routes/principal.rs

@@ -0,0 +1,140 @@
+use crate::{
+    calendar::generate_propfind_calendar_response,
+    depth_extractor::Depth,
+    namespace::Namespace,
+    propfind::{
+        generate_multistatus, parse_propfind, write_invalid_props_response,
+        write_propstat_response, write_resourcetype,
+    },
+    Error,
+};
+use actix_web::{
+    http::{header::ContentType, StatusCode},
+    web::Data,
+    HttpRequest, HttpResponse,
+};
+use actix_web_httpauth::extractors::basic::BasicAuth;
+use anyhow::Result;
+use quick_xml::{
+    events::{BytesText, Event},
+    Writer,
+};
+use rustical_store::calendar::CalendarStore;
+use tokio::sync::RwLock;
+
+// Executes the PROPFIND request and returns a XML string to be written into a <mulstistatus> object.
+pub async fn generate_propfind_principal_response(
+    props: Vec<&str>,
+    principal: &str,
+    path: &str,
+) -> Result<String, quick_xml::Error> {
+    let mut props = props;
+    if props.contains(&"allprops") {
+        props.extend(
+            [
+                "resourcetype",
+                "current-user-principal",
+                "principal-URL",
+                "calendar-home-set",
+                "calendar-user-address-set",
+            ]
+            .iter(),
+        );
+    }
+
+    let mut invalid_props = Vec::<&str>::new();
+
+    let mut output_buffer = Vec::new();
+    let mut writer = Writer::new_with_indent(&mut output_buffer, b' ', 2);
+
+    write_propstat_response(&mut writer, path, StatusCode::OK, |writer| {
+        let writer = writer;
+        for prop in props {
+            match prop {
+                "resourcetype" => write_resourcetype(writer, vec!["principal", "collection"])?,
+                "current-user-principal" | "principal-URL" => {
+                    writer.create_element(prop).write_inner_content(|writer| {
+                        writer
+                            .create_element("href")
+                            // TODO: Replace hard-coded string
+                            .write_text_content(BytesText::new(&format!("/dav/{principal}/",)))?;
+                        Ok(())
+                    })?;
+                }
+                "calendar-home-set" | "calendar-user-address-set" => {
+                    writer
+                        .create_element(&format!("C:{prop}"))
+                        .write_inner_content(|writer| {
+                            writer
+                                .create_element("href")
+                                .write_text_content(BytesText::new(&format!(
+                                    // TODO: Replace hard-coded string
+                                    "/dav/{principal}/"
+                                )))?;
+                            Ok(())
+                        })?;
+                }
+                "allprops" => {}
+                _ => invalid_props.push(prop),
+            };
+        }
+        Ok(())
+    })?;
+
+    dbg!(&invalid_props);
+    write_invalid_props_response(&mut writer, path, invalid_props)?;
+    Ok(std::str::from_utf8(&output_buffer)?.to_string())
+}
+
+pub async fn route_propfind_principal<C: CalendarStore>(
+    body: String,
+    request: HttpRequest,
+    auth: BasicAuth,
+    store: Data<RwLock<C>>,
+    depth: Depth,
+) -> Result<HttpResponse, Error> {
+    let props = parse_propfind(&body).map_err(|_e| Error::BadRequest)?;
+
+    let mut responses = Vec::new();
+    // also get calendars:
+    if depth != Depth::Zero {
+        let cals = store
+            .read()
+            .await
+            .get_calendars()
+            .await
+            .map_err(|_e| Error::InternalError)?;
+
+        for cal in cals {
+            responses.push(
+                generate_propfind_calendar_response(
+                    props.clone(),
+                    auth.user_id(),
+                    &format!("{}/{}", request.path(), cal.id),
+                    &cal,
+                )
+                .map_err(|_e| Error::InternalError)?,
+            );
+        }
+    }
+
+    responses.push(
+        generate_propfind_principal_response(props.clone(), auth.user_id(), request.path())
+            .await
+            .map_err(|_e| Error::InternalError)?,
+    );
+
+    let output = generate_multistatus(vec![Namespace::Dav, Namespace::CalDAV], |writer| {
+        for response in responses {
+            writer.write_event(Event::Text(BytesText::from_escaped(response)))?;
+        }
+        Ok(())
+    })
+    .map_err(|_e| Error::InternalError)?;
+
+    println!("{}", &output);
+
+    Ok(HttpResponse::MultiStatus()
+        .content_type(ContentType::xml())
+        .body(output))
+}

crates/dav/src/routes/root.rs

@@ -0,0 +1,85 @@
+use actix_web::{
+    http::{header::ContentType, StatusCode},
+    HttpRequest, HttpResponse,
+};
+use actix_web_httpauth::extractors::basic::BasicAuth;
+use quick_xml::{
+    events::{BytesText, Event},
+    Writer,
+};
+
+use crate::{
+    namespace::Namespace,
+    propfind::{
+        generate_multistatus, parse_propfind, write_invalid_props_response,
+        write_propstat_response, write_resourcetype,
+    },
+    Error,
+};
+
+// Executes the PROPFIND request and returns a XML string to be written into a <mulstistatus> object.
+pub async fn generate_propfind_root_response(
+    props: Vec<&str>,
+    principal: &str,
+    path: &str,
+) -> Result<String, quick_xml::Error> {
+    let mut props = props;
+    if props.contains(&"allprops") {
+        props.extend(["resourcetype", "current-user-principal"].iter());
+    }
+
+    let mut invalid_props = Vec::<&str>::new();
+
+    let mut output_buffer = Vec::new();
+    let mut writer = Writer::new_with_indent(&mut output_buffer, b' ', 2);
+
+    write_propstat_response(&mut writer, path, StatusCode::OK, |writer| {
+        for prop in props {
+            match prop {
+                "resourcetype" => write_resourcetype(writer, vec!["collection"])?,
+                "current-user-principal" => {
+                    writer
+                        .create_element("current-user-principal")
+                        .write_inner_content(|writer| {
+                            writer
+                                .create_element("href")
+                                .write_text_content(BytesText::new(
+                                    // TODO: Replace hard-coded string
+                                    &format!("/dav/{principal}",),
+                                ))?;
+                            Ok(())
+                        })?;
+                }
+                "allprops" => {}
+                _ => invalid_props.push(prop),
+            };
+        }
+        Ok(())
+    })?;
+    dbg!(&invalid_props);
+    write_invalid_props_response(&mut writer, path, invalid_props)?;
+    Ok(std::str::from_utf8(&output_buffer)?.to_string())
+}
+
+pub async fn route_propfind_root(
+    body: String,
+    request: HttpRequest,
+    auth: BasicAuth,
+) -> Result<HttpResponse, Error> {
+    let props = parse_propfind(&body).map_err(|_e| Error::BadRequest)?;
+
+    let responses_string =
+        generate_propfind_root_response(props.clone(), auth.user_id(), request.path())
+            .await
+            .map_err(|_e| Error::InternalError)?;
+
+    let output = generate_multistatus(vec![Namespace::Dav, Namespace::CalDAV], |writer| {
+        writer.write_event(Event::Text(BytesText::from_escaped(responses_string)))?;
+        Ok(())
+    })
+    .map_err(|_e| Error::InternalError)?;
+
+    Ok(HttpResponse::MultiStatus()
+        .content_type(ContentType::xml())
+        .body(output))
+}

crates/store/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "rustical_store"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+anyhow = { version = "1.0.75", features = ["backtrace"] }
+async-trait = "0.1.73"
+serde = { version = "1.0.188", features = ["derive", "rc"] }
+serde_json = "1.0.105"
+sha2 = "0.10.7"
+sqlx = { version = "0.7.1", features = ["sqlx-sqlite", "sqlx-postgres", "uuid", "time", "chrono", "postgres", "sqlite", "runtime-tokio"] }
+tokio = { version = "1.32.0", features = ["sync", "full"] }

crates/store/src/calendar.rs

@@ -0,0 +1,108 @@
+use std::collections::HashMap;
+
+use anyhow::{anyhow, Result};
+use async_trait::async_trait;
+use serde::{Deserialize, Serialize};
+use sha2::{Digest, Sha256};
+use tokio::{fs::File, io::AsyncWriteExt};
+
+#[derive(Debug, Clone, Deserialize, Serialize)]
+pub struct Event {
+    uid: String,
+    ics: String,
+}
+
+impl Event {
+    pub fn get_uid(&self) -> &str {
+        &self.uid
+    }
+    pub fn get_etag(&self) -> String {
+        let mut hasher = Sha256::new();
+        hasher.update(&self.uid);
+        hasher.update(self.to_ics());
+        format!("{:x}", hasher.finalize())
+    }
+
+    pub fn to_ics(&self) -> &str {
+        &self.ics
+    }
+}
+
+#[derive(Debug, Clone, Deserialize, Serialize)]
+pub struct Calendar {
+    pub id: String,
+    pub name: Option<String>,
+    pub ics: String,
+}
+
+impl Calendar {}
+
+#[async_trait]
+pub trait CalendarStore: Send + Sync + 'static {
+    async fn get_calendar(&self, id: &str) -> Result<Calendar>;
+    async fn get_calendars(&self) -> Result<Vec<Calendar>>;
+
+    async fn get_events(&self, cid: &str) -> Result<Vec<Event>>;
+    async fn get_event(&self, uid: &str) -> Result<Event>;
+    async fn upsert_event(&mut self, uid: String, ics: String) -> Result<()>;
+    async fn delete_event(&mut self, uid: &str) -> Result<()>;
+}
+
+#[derive(Debug, Deserialize, Serialize)]
+pub struct JsonCalendarStore {
+    calendars: HashMap<String, Calendar>,
+    events: HashMap<String, Event>,
+    path: String,
+}
+
+impl JsonCalendarStore {
+    pub fn new(path: String) -> Self {
+        JsonCalendarStore {
+            calendars: HashMap::new(),
+            events: HashMap::new(),
+            path,
+        }
+    }
+
+    pub async fn save(&self) -> Result<()> {
+        let mut file = File::create(&self.path).await?;
+        let json = serde_json::to_string_pretty(&self)?;
+        file.write_all(json.as_bytes()).await?;
+        Ok(())
+    }
+}
+
+#[async_trait]
+impl CalendarStore for JsonCalendarStore {
+    async fn get_calendar(&self, id: &str) -> Result<Calendar> {
+        Ok(self.calendars.get(id).ok_or(anyhow!("not found"))?.clone())
+    }
+
+    async fn get_calendars(&self) -> Result<Vec<Calendar>> {
+        Ok(vec![Calendar {
+            id: "test".to_string(),
+            name: Some("test".to_string()),
+            ics: "asd".to_string(),
+        }])
+    }
+
+    async fn get_events(&self, _cid: &str) -> Result<Vec<Event>> {
+        Ok(self.events.values().cloned().collect())
+    }
+
+    async fn get_event(&self, uid: &str) -> Result<Event> {
+        Ok(self.events.get(uid).ok_or(anyhow!("not found"))?.clone())
+    }
+
+    async fn upsert_event(&mut self, uid: String, ics: String) -> Result<()> {
+        self.events.insert(uid.clone(), Event { uid, ics });
+        self.save().await.unwrap();
+        Ok(())
+    }
+
+    async fn delete_event(&mut self, uid: &str) -> Result<()> {
+        self.events.remove(uid);
+        self.save().await?;
+        Ok(())
+    }
+}

crates/store/src/lib.rs

@@ -0,0 +1,2 @@
+pub mod calendar;
+pub mod users;

crates/store/src/users.rs

@@ -0,0 +1,39 @@
+use anyhow::{anyhow, Result};
+use async_trait::async_trait;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Deserialize, Serialize)]
+pub struct User {
+    pub id: String,
+    pub name: Option<String>,
+}
+
+impl User {}
+
+#[async_trait]
+pub trait UserStore: Send + Sync + 'static {
+    async fn get_user(&self, id: &str) -> Result<User>;
+    async fn get_users(&self) -> Result<Vec<User>>;
+}
+
+pub struct TestUserStore {}
+
+#[async_trait]
+impl UserStore for TestUserStore {
+    async fn get_user(&self, id: &str) -> Result<User> {
+        if id != "test" {
+            return Err(anyhow!("asd"));
+        }
+        Ok(User {
+            id: "test".to_string(),
+            name: Some("test".to_string()),
+        })
+    }
+
+    async fn get_users(&self) -> Result<Vec<User>> {
+        Ok(vec![User {
+            id: "test".to_string(),
+            name: Some("test".to_string()),
+        }])
+    }
+}

src/config.rs

@@ -0,0 +1,17 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Deserialize, Serialize)]
+pub struct JsonCalendarStoreConfig {
+    pub db_path: String,
+}
+
+#[derive(Debug, Deserialize, Serialize)]
+#[serde(tag = "backend", rename_all = "snake_case")]
+pub enum CalendarStoreConfig {
+    Json(JsonCalendarStoreConfig),
+}
+
+#[derive(Debug, Deserialize, Serialize)]
+pub struct Config {
+    pub calendar_store: CalendarStoreConfig,
+}

src/main.rs

@@ -0,0 +1,63 @@
+use std::fs;
+use std::sync::Arc;
+
+use crate::config::Config;
+use actix_web::middleware::{Logger, NormalizePath};
+use actix_web::{web, App, HttpServer};
+use anyhow::Result;
+use clap::Parser;
+use config::{CalendarStoreConfig, JsonCalendarStoreConfig};
+use rustical_api::configure_api;
+use rustical_dav::{configure_dav, configure_well_known};
+use rustical_store::calendar::JsonCalendarStore;
+use tokio::sync::RwLock;
+
+mod config;
+
+#[derive(Parser, Debug)]
+#[command(author, version, about, long_about = None)]
+struct Args {
+    #[arg(short, long, env)]
+    config_file: String,
+}
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    env_logger::init_from_env(env_logger::Env::default().default_filter_or("info"));
+
+    let args = Args::parse();
+    let config: Config = toml::from_str(&fs::read_to_string(&args.config_file)?)?;
+    // TODO: Clean this jank up as soon more configuration options appear
+    let db_path = match config.calendar_store {
+        CalendarStoreConfig::Json(JsonCalendarStoreConfig { db_path }) => db_path,
+    };
+
+    let cal_store = Arc::new(RwLock::new(
+        if let Ok(json) = fs::read_to_string(&db_path) {
+            serde_json::from_str::<JsonCalendarStore>(&json)?
+        } else {
+            JsonCalendarStore::new(db_path.to_string())
+        },
+    ));
+
+    HttpServer::new(move || {
+        let cal_store = cal_store.clone();
+        App::new()
+            .wrap(Logger::new("[%s] %r"))
+            .wrap(NormalizePath::trim())
+            .service(
+                web::scope("/dav").configure(|cfg| configure_dav(cfg, cal_store.clone().into())),
+            )
+            .service(
+                web::scope("/.well-known")
+                    .configure(|cfg| configure_well_known(cfg, "/dav".to_string())),
+            )
+            .service(
+                web::scope("/api").configure(|cfg| configure_api(cfg, cal_store.clone().into())),
+            )
+    })
+    .bind(("0.0.0.0", 4000))?
+    .run()
+    .await?;
+    Ok(())
+}