io_webdav/rfc4791/item/update.rs
1//! `update-item` coroutine: PUT raw iCalendar bytes against an
2//! existing calendar item.
3//!
4//! Supports the optional `If-Match` precondition so callers can gate
5//! the write on the last-known ETag (RFC 9110 ยง13.1.1).
6//!
7//! # Example
8//!
9//! ```rust,no_run
10//! use std::{
11//! io::{Read, Write},
12//! net::TcpStream,
13//! };
14//!
15//! use io_webdav::{
16//! coroutine::{WebdavCoroutine, WebdavCoroutineState, WebdavYield},
17//! rfc4791::item::update::UpdateItem,
18//! rfc4918::WebdavAuth,
19//! };
20//! use url::Url;
21//!
22//! // Ready stream needed (TCP-connected, TLS-negociated)
23//! let mut stream = TcpStream::connect("dav.example.org:443").unwrap();
24//! let mut buf = [0u8; 4096];
25//!
26//! let base_url: Url = "https://dav.example.org/".parse().unwrap();
27//! let auth = WebdavAuth::None;
28//! let ical = b"BEGIN:VCALENDAR\r\n...\r\nEND:VCALENDAR\r\n".to_vec();
29//! let mut coroutine = UpdateItem::new(
30//! &base_url,
31//! &auth,
32//! "io-webdav",
33//! "/dav/calendars/personal/",
34//! "event-1",
35//! ical,
36//! Some("\"abc123\""),
37//! );
38//! let mut arg = None;
39//!
40//! let updated = loop {
41//! match coroutine.resume(arg.take()) {
42//! WebdavCoroutineState::Yielded(WebdavYield::WantsWrite(bytes)) => {
43//! stream.write_all(&bytes).unwrap();
44//! }
45//! WebdavCoroutineState::Yielded(WebdavYield::WantsRead) => {
46//! let n = stream.read(&mut buf).unwrap();
47//! arg = Some(&buf[..n]);
48//! }
49//! WebdavCoroutineState::Complete(Ok(updated)) => break updated,
50//! WebdavCoroutineState::Complete(Err(err)) => panic!("{err}"),
51//! }
52//! };
53//!
54//! println!("updated {} (etag {:?})", updated.id, updated.etag);
55//! ```
56
57use core::mem;
58
59use alloc::{
60 string::{String, ToString},
61 vec::Vec,
62};
63
64use log::trace;
65use url::Url;
66
67use crate::{
68 coroutine::*,
69 rfc4791::item::join_path,
70 rfc4918::{
71 WebdavAuth,
72 put::{Put, PutArgs},
73 read_etag,
74 send::{SendError, SendOk},
75 },
76 webdav_try,
77};
78
79/// Coroutine that updates a calendar item.
80#[derive(Debug)]
81pub struct UpdateItem {
82 id: String,
83 state: State,
84}
85
86impl UpdateItem {
87 /// Builds a new `update-item` coroutine.
88 pub fn new(
89 base_url: &Url,
90 auth: &WebdavAuth,
91 user_agent: &str,
92 calendar_path: &str,
93 id: &str,
94 ical: Vec<u8>,
95 if_match: Option<&str>,
96 ) -> Self {
97 let path = join_path(calendar_path, id);
98 let put = Put::new(PutArgs {
99 base_url,
100 auth,
101 user_agent,
102 path: &path,
103 content_type: "text/calendar; charset=utf-8",
104 body: ical,
105 if_match,
106 if_none_match: None,
107 });
108 Self {
109 id: id.to_string(),
110 state: State::Put(put),
111 }
112 }
113}
114
115impl WebdavCoroutine for UpdateItem {
116 type Yield = WebdavYield;
117 type Return = Result<UpdateItemOk, SendError>;
118
119 fn resume(&mut self, arg: Option<&[u8]>) -> WebdavCoroutineState<Self::Yield, Self::Return> {
120 trace!("sending request");
121 match &mut self.state {
122 State::Put(put) => {
123 let SendOk { response, .. } = webdav_try!(put, arg);
124 let etag = read_etag(&response);
125 let id = mem::take(&mut self.id);
126 WebdavCoroutineState::Complete(Ok(UpdateItemOk { id, etag }))
127 }
128 }
129 }
130}
131
132#[derive(Debug)]
133enum State {
134 Put(Put),
135}
136
137/// Outcome of a successful
138/// [`UpdateItem`] resume.
139#[derive(Clone, Debug)]
140pub struct UpdateItemOk {
141 /// Item identifier (as supplied by the caller).
142 pub id: String,
143 /// Updated entity tag returned by the server, when present.
144 pub etag: Option<String>,
145}