From: Dominik Csapak <d.csapak@proxmox.com>
To: pbs-devel@lists.proxmox.com
Subject: [pbs-devel] [RFC PATCH proxmox 1/4] proxmox-async: add SenderWriter helper
Date: Thu, 17 Feb 2022 10:40:35 +0100 [thread overview]
Message-ID: <20220217094041.1632033-2-d.csapak@proxmox.com> (raw)
In-Reply-To: <20220217094041.1632033-1-d.csapak@proxmox.com>
this wraps around a tokio Sender for Vec<u8>, but implements a blocking
write. We can use thas as an adapter for something that only takes a
writer, and can read from it asynchonously
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
proxmox-async/src/blocking/mod.rs | 3 ++
proxmox-async/src/blocking/sender_writer.rs | 47 +++++++++++++++++++++
2 files changed, 50 insertions(+)
create mode 100644 proxmox-async/src/blocking/sender_writer.rs
diff --git a/proxmox-async/src/blocking/mod.rs b/proxmox-async/src/blocking/mod.rs
index 28247b3..06f821a 100644
--- a/proxmox-async/src/blocking/mod.rs
+++ b/proxmox-async/src/blocking/mod.rs
@@ -9,3 +9,6 @@ pub use tokio_writer_adapter::TokioWriterAdapter;
mod wrapped_reader_stream;
pub use wrapped_reader_stream::WrappedReaderStream;
+
+mod sender_writer;
+pub use sender_writer::SenderWriter;
diff --git a/proxmox-async/src/blocking/sender_writer.rs b/proxmox-async/src/blocking/sender_writer.rs
new file mode 100644
index 0000000..62682e5
--- /dev/null
+++ b/proxmox-async/src/blocking/sender_writer.rs
@@ -0,0 +1,47 @@
+use std::io;
+
+use anyhow::Error;
+use tokio::sync::mpsc::Sender;
+
+/// Wrapper struct around [`tokio::sync::mpsc::Sender`] for `Result<Vec<u8>, Error>` that implements [`std::io::Write`]
+pub struct SenderWriter {
+ sender: Sender<Result<Vec<u8>, Error>>,
+}
+
+impl SenderWriter {
+ pub fn from_sender(sender: tokio::sync::mpsc::Sender<Result<Vec<u8>, Error>>) -> Self {
+ Self { sender }
+ }
+
+ fn write_impl(&mut self, buf: &[u8]) -> io::Result<usize> {
+ if let Err(err) = self.sender.blocking_send(Ok(buf.to_vec())) {
+ return Err(io::Error::new(
+ io::ErrorKind::UnexpectedEof,
+ format!("could not send: {}", err),
+ ));
+ }
+
+ Ok(buf.len())
+ }
+
+ fn flush_impl(&mut self) -> io::Result<()> {
+ Ok(())
+ }
+}
+
+impl io::Write for SenderWriter {
+ fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+ self.write_impl(buf)
+ }
+
+ fn flush(&mut self) -> io::Result<()> {
+ self.flush_impl()
+ }
+}
+
+impl Drop for SenderWriter {
+ fn drop(&mut self) {
+ // ignore errors
+ let _ = self.flush_impl();
+ }
+}
--
2.30.2
next prev parent reply other threads:[~2022-02-17 9:40 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-17 9:40 [pbs-devel] [RFC PATCH proxmox/proxmox-backup] implement streaming serialization for api calls Dominik Csapak
2022-02-17 9:40 ` Dominik Csapak [this message]
2022-02-17 9:40 ` [pbs-devel] [RFC PATCH proxmox 2/4] promxox-router: add SerializableReturn Trait Dominik Csapak
2022-02-18 8:21 ` Dietmar Maurer
2022-02-17 9:40 ` [pbs-devel] [RFC PATCH proxmox 3/4] proxmox-router: add new ApiHandler variants for streaming serialization Dominik Csapak
2022-02-17 9:40 ` [pbs-devel] [RFC PATCH proxmox 4/4] proxmox-api-macro: add 'streaming' option Dominik Csapak
2022-02-17 9:40 ` [pbs-devel] [RFC PATCH proxmox-backup 1/3] proxmox-rest-server: OutputFormatter: add new format_data_streaming method Dominik Csapak
2022-02-23 9:20 ` Thomas Lamprecht
2022-02-17 9:40 ` [pbs-devel] [RFC PATCH proxmox-backup 2/3] adapt to the new ApiHandler variants Dominik Csapak
2022-02-17 9:40 ` [pbs-devel] [RFC PATCH proxmox-backup 3/3] api: admin/datastore: enable streaming for some api calls Dominik Csapak
2022-02-18 7:36 [pbs-devel] [RFC PATCH proxmox 1/4] proxmox-async: add SenderWriter helper Dietmar Maurer
2022-02-18 15:27 ` Wolfgang Bumiller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220217094041.1632033-2-d.csapak@proxmox.com \
--to=d.csapak@proxmox.com \
--cc=pbs-devel@lists.proxmox.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox