Files
taskwarrior-2.x/taskchampion/src/server/remote/mod.rs
2020-12-28 21:32:59 +00:00

120 lines
4.1 KiB
Rust

use crate::server::{AddVersionResult, GetVersionResult, HistorySegment, Server, VersionId};
use failure::{format_err, Fallible};
use std::convert::TryInto;
use uuid::Uuid;
mod crypto;
use crypto::{HistoryCiphertext, HistoryCleartext, Secret};
pub struct RemoteServer {
origin: String,
client_key: Uuid,
encryption_secret: Secret,
agent: ureq::Agent,
}
/// A RemoeServer communicates with a remote server over HTTP (such as with
/// taskchampion-sync-server).
impl RemoteServer {
/// Construct a new RemoteServer. The `origin` is the sync server's protocol and hostname
/// without a trailing slash, such as `https://tcsync.example.com`. Pass a client_key to
/// identify this client to the server. Multiple replicas synchronizing the same task history
/// should use the same client_key.
pub fn new(origin: String, client_key: Uuid, encryption_secret: Vec<u8>) -> RemoteServer {
RemoteServer {
origin,
client_key,
encryption_secret: encryption_secret.into(),
agent: ureq::agent(),
}
}
}
/// Convert a ureq::Response to an Error
fn resp_to_error(resp: ureq::Response) -> failure::Error {
return format_err!(
"error {}: {}",
resp.status(),
resp.into_string()
.unwrap_or_else(|e| format!("(could not read response: {})", e))
);
}
/// Read a UUID-bearing header or fail trying
fn get_uuid_header(resp: &ureq::Response, name: &str) -> Fallible<Uuid> {
let value = resp
.header(name)
.ok_or_else(|| format_err!("Response does not have {} header", name))?;
let value = Uuid::parse_str(value)
.map_err(|e| format_err!("{} header is not a valid UUID: {}", name, e))?;
Ok(value)
}
impl Server for RemoteServer {
fn add_version(
&mut self,
parent_version_id: VersionId,
history_segment: HistorySegment,
) -> Fallible<AddVersionResult> {
let url = format!(
"{}/client/{}/add-version/{}",
self.origin, self.client_key, parent_version_id
);
let history_cleartext = HistoryCleartext {
parent_version_id,
history_segment,
};
let history_ciphertext = history_cleartext.seal(&self.encryption_secret)?;
let resp = self
.agent
.post(&url)
.timeout_connect(10_000)
.timeout_read(60_000)
.set(
"Content-Type",
"application/vnd.taskchampion.history-segment",
)
.send_bytes(history_ciphertext.as_ref());
if resp.ok() {
let version_id = get_uuid_header(&resp, "X-Version-Id")?;
Ok(AddVersionResult::Ok(version_id))
} else if resp.status() == 409 {
let parent_version_id = get_uuid_header(&resp, "X-Parent-Version-Id")?;
Ok(AddVersionResult::ExpectedParentVersion(parent_version_id))
} else {
Err(resp_to_error(resp))
}
}
fn get_child_version(&mut self, parent_version_id: VersionId) -> Fallible<GetVersionResult> {
let url = format!(
"{}/client/{}/get-child-version/{}",
self.origin, self.client_key, parent_version_id
);
let resp = self
.agent
.get(&url)
.timeout_connect(10_000)
.timeout_read(60_000)
.call();
if resp.ok() {
let parent_version_id = get_uuid_header(&resp, "X-Parent-Version-Id")?;
let version_id = get_uuid_header(&resp, "X-Version-Id")?;
let history_ciphertext: HistoryCiphertext = resp.try_into()?;
let history_segment = history_ciphertext
.open(&self.encryption_secret, parent_version_id)?
.history_segment;
Ok(GetVersionResult::Version {
version_id,
parent_version_id,
history_segment,
})
} else if resp.status() == 404 {
Ok(GetVersionResult::NoSuchVersion)
} else {
Err(resp_to_error(resp))
}
}
}