Crates.io | netidx-tools |
lib.rs | netidx-tools |
version | 0.27.0 |
source | src |
created_at | 2020-05-23 21:57:39.843677 |
updated_at | 2024-11-19 18:02:24.715755 |
description | netidx command line tools |
homepage | https://netidx.github.io/netidx-book/ |
repository | https://github.com/estokes/netidx |
max_upload_size | |
id | 245001 |
size | 199,728 |
Netidx is middleware that enables publishing a value, like 42, in one program and consuming it in another program, either on the same machine or across the network.
Values are given globally unique names in a hierarchical namespace. For example our published 42 might be named /the-ultimate-answer (normally we wouldn't put values directly under the root, but in this case it's appropriate). Any other program on the network can refer to 42 by that name, and will receive updates in the (unlikely) event that /the-ultimate-answer changes.
Like LDAP
Unlike LDAP
Like MQTT
Unlike MQTT
For more details see the netidx book
Here is an example service that publishes a cpu temperature, along with the corresponding subscriber that consumes the data.
use netidx::{
publisher::{Publisher, Value, BindCfg},
config::Config,
resolver::Auth,
path::Path,
};
use tokio::time;
use std::time::Duration;
use anyhow::Result;
fn get_cpu_temp() -> f32 { 42. }
async fn run() -> Result<()> {
// load the site cluster config. You can also just use a file.
let cfg = Config::load_default()?;
// no authentication (kerberos v5 is the other option)
// listen on any unique address matching 192.168.0.0/16
let publisher = Publisher::new(cfg, Auth::Anonymous, "192.168.0.0/16".parse()?).await?;
let temp = publisher.publish(
Path::from("/hw/washu-chan/cpu-temp"),
Value::F32(get_cpu_temp())
)?;
loop {
time::sleep(Duration::from_millis(500)).await;
let mut batch = publisher.start_batch();
temp.update(&mut batch, Value::F32(get_cpu_temp()));
batch.commit(None).await;
}
Ok(())
}
use netidx::{
subscriber::{Subscriber, UpdatesFlags},
config::Config,
resolver::Auth,
path::Path,
};
use futures::{prelude::*, channel::mpsc};
use anyhow::Result;
async fn run() -> Result<()> {
let cfg = Config::load_default()?;
let subscriber = Subscriber::new(cfg, Auth::Anonymous)?;
let path = Path::from("/hw/washu-chan/cpu-temp");
let temp = subscriber.subscribe_one(path, None).await?;
println!("washu-chan cpu temp is: {:?}", temp.last());
let (tx, mut rx) = mpsc::channel(10);
temp.updates(UpdatesFlags::empty(), tx);
while let Some(mut batch) = rx.next().await {
for (_, v) in batch.drain(..) {
println!("washu-chan cpu temp is: {:?}", v);
}
}
Ok(())
}
Published things always have a value, which new subscribers receive
initially. Thereafter a subscription is a lossless ordered stream,
just like a tcp connection, except that instead of bytes
publisher::Value
is the unit of transmission. Since the subscriber
can write values back to the publisher, the connection is
bidirectional, also like a Tcp stream.
Values include many useful primitives, including zero copy bytes buffers (using the awesome bytes crate), so you can easily use netidx to efficiently send any kind of message you like. However it's advised to stick to primitives and express structure with multiple published values in a hierarchy, since this makes your system more discoverable, and is also quite efficient.
netidx includes optional support for kerberos v5 (including Active Directory). If enabled, all components will do mutual authentication between the resolver, subscriber, and publisher as well as encryption of all data on the wire.
In krb5 mode the resolver server maintains and enforces a set of authorization permissions for the entire namespace. The system administrator can centrally enforce who can publish where, and who can subscribe to what.