implement value listing

Cargo.lock

@@ -24,6 +24,15 @@ version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
 
+[[package]]
+name = "aho-corasick"
+version = "1.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ddd31a130427c27518df266943a5308ed92d4b226cc639f5a8f1002816174301"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "aligned"
 version = "0.4.3"
@@ -929,6 +938,9 @@ dependencies = [
 [[package]]
 name = "protocol"
 version = "0.1.0"
+dependencies = [
+ "regex",
+]
 
 [[package]]
 name = "pxfm"
@@ -1081,6 +1093,35 @@ dependencies = [
  "crossbeam-utils",
 ]
 
+[[package]]
+name = "regex"
+version = "1.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e10754a14b9137dd7b1e3e5b0493cc9171fdd105e0ab477f51b72e7f3ac0e276"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e1dd4122fc1595e8162618945476892eefca7b88c52820e74af6262213cae8f"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc897dd8d9e8bd1ed8cdad82b5966c3e0ecae09fb1907d58efaa013543185d0a"
+
 [[package]]
 name = "rgb"
 version = "0.8.53"

protocol/Cargo.toml

@@ -4,3 +4,4 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
+regex = "1"

protocol/src/message.rs

@@ -4,6 +4,18 @@ pub fn create_request_message(value: &String) -> String {
     format!("GETVAL {}\n", value)
 }
 
+pub fn create_list_message() -> String {
+    format!("LISTVAL\n")
+}
+
+pub fn parse_list_response(lines: Vec<String>) -> Vec<String> {
+    lines
+        .iter()
+        .filter_map(|l| l.split(" ").last())
+        .map(|l| l.into())
+        .collect()
+}
+
 pub fn parse_response_header(header: String) -> Result<i32, ProtocolError> {
     let num_values_raw = header
         .split(" ")
@@ -118,4 +130,27 @@ mod tests {
         assert!(result.is_err());
         assert_eq!(result, Err(ProtocolError::EmptyResponse));
     }
+
+    #[test]
+    fn test_parse_list_response() {
+        let resp = vec![
+            "1780776337.692 tp-on/cpu-9/cpu-steal",
+            "1780776337.692 tp-on/cpu-9/cpu-system",
+            "1780776337.692 tp-on/cpu-9/cpu-user",
+            "1780776337.692 tp-on/cpu-9/cpu-wait",
+        ]
+        .iter()
+        .map(|s| s.to_string())
+        .collect();
+        let result = parse_list_response(resp);
+        assert_eq!(
+            result,
+            vec![
+                "tp-on/cpu-9/cpu-steal",
+                "tp-on/cpu-9/cpu-system",
+                "tp-on/cpu-9/cpu-user",
+                "tp-on/cpu-9/cpu-wait",
+            ]
+        );
+    }
 }

protocol/src/protocol.rs

@@ -2,7 +2,10 @@ use std::io::{Read, Write};
 use std::os::unix::net::UnixStream;
 
 use crate::err::ProtocolError;
-use crate::message::{create_request_message, parse_response_header, parse_response_message};
+use crate::message::{
+    create_list_message, create_request_message, parse_list_response, parse_response_header,
+    parse_response_message,
+};
 
 pub struct Protocol {
     socket: UnixStream,
@@ -34,6 +37,27 @@ impl Protocol {
 
     pub fn get(&mut self, path: String, name: String) -> Result<f32, ProtocolError> {
         let req = create_request_message(&path);
+        let lines = self.rpc(&req)?;
+
+        if lines.len() < 1 {
+            Err(ProtocolError::ValueNotFound(name, vec![]))
+        } else {
+            parse_response_message(lines, name)
+        }
+    }
+
+    pub fn list(&mut self, path_regex: &Regex) -> Result<Vec<String>, ProtocolError> {
+        let req = create_list_message();
+        let lines = self.rpc(&req)?;
+        let values = parse_list_response(lines);
+
+        Ok(values
+            .into_iter()
+            .filter(|v| path_regex.is_match(v))
+            .collect())
+    }
+
+    fn rpc(&mut self, req: &str) -> Result<Vec<String>, ProtocolError> {
         let raw_req = req.as_bytes();
         self.socket
             .write_all(raw_req)
@@ -41,13 +65,8 @@ impl Protocol {
 
         let header = self.read_line()?;
         let num_values = parse_response_header(header)?;
-        if num_values < 1 {
-            Err(ProtocolError::ValueNotFound(name, vec![]))
-        } else {
-            let lines = (0..num_values)
-                .map(|_| self.read_line())
-                .collect::<Result<Vec<String>, ProtocolError>>()?;
-            parse_response_message(lines, name)
-        }
+        (0..num_values)
+            .map(|_| self.read_line())
+            .collect::<Result<Vec<String>, ProtocolError>>()
     }
 }