Struct PvaClient 

pub struct PvaClient { /* private fields */ }

High-level PVAccess client.

Provides pvget, pvput, pvmonitor, and pvinfo methods that hide the underlying protocol handshake.

let client = PvaClient::builder().build();
let val = client.pvget("MY:PV").await?;

Implementations

impl PvaClient

pub fn builder() -> PvaClientBuilder

Create a builder for configuring a PvaClient.

pub async fn pvget(&self, pv_name: &str) -> Result<PvGetResult, PvGetError>

Fetch the current value of a PV.

pub async fn pvput( &self, pv_name: &str, value: impl Into<Value>, ) -> Result<(), PvGetError>

Write a value to a PV.

Accepts anything convertible to serde_json::Value:

client.pvput("MY:PV", 42.0).await?;
client.pvput("MY:PV", "hello").await?;
client.pvput("MY:PV", serde_json::json!({"value": 1.5})).await?;

pub async fn open_put_channel( &self, pv_name: &str, ) -> Result<PvaChannel, PvGetError>

Open a persistent channel for high-rate PUT streaming.

Resolves the PV, establishes a channel, and completes the PUT INIT handshake. The returned PvaChannel is ready for immediate put calls.

pub async fn pvmonitor<F>( &self, pv_name: &str, callback: F, ) -> Result<(), PvGetError>

where F: FnMut(&DecodedValue) -> ControlFlow<()>,

Subscribe to a PV and receive live updates via a callback.

The callback returns ControlFlow::Continue to keep listening or ControlFlow::Break to stop the subscription.

use std::ops::ControlFlow;

client.pvmonitor("MY:PV", |value| {
    println!("{value:?}");
    ControlFlow::Continue(())
}).await?;

pub async fn pvinfo(&self, pv_name: &str) -> Result<StructureDesc, PvGetError>

Retrieve the field/structure description (introspection) for a PV.

pub async fn pvlist( &self, server_addr: SocketAddr, ) -> Result<Vec<String>, PvGetError>

List PV names served by a specific server (via __pvlist GET).

pub async fn pvlist_with_fallback( &self, server_addr: SocketAddr, ) -> Result<(Vec<String>, PvListSource), PvGetError>

List PV names with automatic fallback through all strategies.

Tries: __pvlist → GET_FIELD (opt-in) → Server RPC → Server GET.

Trait Implementations

impl Clone for PvaClient

fn clone(&self) -> PvaClient

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for PvaClient

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.