Fetches the calendar home set

src/data/client.rs

@@ -1,7 +1,168 @@
-pub struct Client {}
+//! Code to connect to a Caldav server
+//!
+//! Some of it comes from https://github.com/marshalshi/caldav-client-rust.git
+
+use std::error::Error;
+
+use reqwest::Method;
+use reqwest::header::CONTENT_TYPE;
+use minidom::Element;
+use url::Url;
+
+static DAVCLIENT_BODY: &str = r#"
+    <d:propfind xmlns:d="DAV:">
+       <d:prop>
+           <d:current-user-principal />
+       </d:prop>
+    </d:propfind>
+"#;
+
+static HOMESET_BODY: &str = r#"
+    <d:propfind xmlns:d="DAV:" xmlns:c="urn:ietf:params:xml:ns:caldav" >
+      <d:self/>
+      <d:prop>
+        <c:calendar-home-set />
+      </d:prop>
+    </d:propfind>
+"#;
+
+pub struct Client {
+    url: Url,
+    username: String,
+    password: String,
+
+    principal: Option<Url>,
+    calendar_home_set: Option<Url>,
+}
 
 impl Client {
-    pub fn new(&mut self, url: String, username: String, password: String) -> Self {
-        Self{}
+    pub fn new<S: AsRef<str>, T: ToString, U: ToString>(url: S, username: T, password: U) -> Result<Self, Box<dyn Error>> {
+        let url = Url::parse(url.as_ref())?;
+
+        Ok(Self{
+            url,
+            username: username.to_string(),
+            password: password.to_string(),
+            principal: None,
+            calendar_home_set: None,
+        })
     }
-}
+
+    /// Return the Principal URL, or fetch it from server if not known yet
+    async fn get_principal(&mut self) -> Result<Url, Box<dyn Error>> {
+        if let Some(p) = &self.principal {
+            return Ok(p.clone());
+        }
+
+        let method = Method::from_bytes(b"PROPFIND")
+            .expect("cannot create PROPFIND method.");
+
+        let res = reqwest::Client::new()
+            .request(method, self.url.as_str())
+            .header("Depth", 0)
+            .header(CONTENT_TYPE, "application/xml")
+            .basic_auth(self.username.clone(), Some(self.password.clone()))
+            .body(DAVCLIENT_BODY)
+            .send()
+            .await?;
+        let text = res.text().await?;
+
+        let root: Element = text.parse().unwrap();
+        let principal = find_elem(&root, "current-user-principal".to_string()).unwrap();
+        let principal_href = find_elem(principal, "href".to_string()).unwrap();
+        let h_str = principal_href.text();
+
+        eprintln!("URL is {}", h_str);
+
+        let mut principal_url = self.url.clone();
+        principal_url.set_path(&h_str);
+        self.principal = Some(principal_url.clone());
+
+        return Ok(principal_url);
+    }
+
+    /// Return the Homeset URL, or fetch it from server if not known yet
+    async fn get_cal_home_set(&mut self) -> Result<Url, Box<dyn Error>> {
+        if let Some(h) = &self.calendar_home_set {
+            return Ok(h.clone());
+        }
+        let principal_url = self.get_principal().await?;
+
+        let method = Method::from_bytes(b"PROPFIND")
+            .expect("cannot create PROPFIND method. principal");
+
+        let res = reqwest::Client::new()
+            .request(method, principal_url.as_str())
+            .header("Depth", 0)
+            .header(CONTENT_TYPE, "application/xml")
+            .basic_auth(self.username.clone(), Some(self.password.clone()))
+            .body(HOMESET_BODY)
+            .send()
+            .await?;
+
+        let text = res.text().await?;
+
+        let root: Element = text.parse().unwrap();
+        let chs = find_elem(&root, "calendar-home-set".to_string()).unwrap();
+        let chs_href = find_elem(chs, "href".to_string()).unwrap();
+        let chs_str = chs_href.text();
+
+        let mut chs_url = self.url.clone();
+        chs_url.set_path(&chs_str);
+        println!("Calendar home set {:?}", chs_url.path());
+        self.calendar_home_set = Some(chs_url.clone());
+
+        Ok(chs_url)
+    }
+}
+
+
+
+pub fn find_elems(root: &Element, tag: String) -> Vec<&Element> {
+    let mut elems: Vec<&Element> = Vec::new();
+
+    for el in root.children() {
+        if el.name() == tag {
+            elems.push(el);
+        } else {
+            let ret = find_elems(el, tag.clone());
+            elems.extend(ret);
+        }
+    }
+    elems
+}
+
+pub fn find_elem(root: &Element, tag: String) -> Option<&Element> {
+    if root.name() == tag {
+        return Some(root);
+    }
+
+    for el in root.children() {
+        if el.name() == tag {
+            return Some(el);
+        } else {
+            let ret = find_elem(el, tag.clone());
+            if ret.is_some() {
+                return ret;
+            }
+        }
+    }
+    None
+}
+
+
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    use crate::settings::URL;
+    use crate::settings::USERNAME;
+    use crate::settings::PASSWORD;
+
+    #[tokio::test]
+    async fn test_client() {
+        let mut client = Client::new(URL, USERNAME, PASSWORD).unwrap();
+        client.get_cal_home_set().await.unwrap();
+    }
+}