fix(ext/kv): add a warning for listenQueue if used with remote KV (#20341)

Cargo.lock

@@ -1301,6 +1301,7 @@ dependencies = [
  "rusqlite",
  "serde",
  "serde_json",
+ "termcolor",
  "tokio",
  "url",
  "uuid",

Cargo.toml

@@ -137,6 +137,7 @@ smallvec = "1.8"
 socket2 = { version = "0.5.3", features = ["all"] }
 tar = "=0.4.40"
 tempfile = "3.4.0"
+termcolor = "1.1.3"
 thiserror = "1.0.40"
 tokio = { version = "1.28.1", features = ["full"] }
 tokio-metrics = { version = "0.3.0", features = ["rt"] }

ext/kv/Cargo.toml

@@ -29,6 +29,7 @@ reqwest.workspace = true
 rusqlite.workspace = true
 serde.workspace = true
 serde_json.workspace = true
+termcolor.workspace = true
 tokio.workspace = true
 url.workspace = true
 uuid = { workspace = true, features = ["serde"] }

ext/kv/remote.rs

@@ -1,6 +1,8 @@
 // Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
 
 use std::cell::RefCell;
+use std::fmt;
+use std::io::Write;
 use std::marker::PhantomData;
 use std::rc::Rc;
 use std::sync::Arc;
@@ -29,6 +31,10 @@ use deno_core::OpState;
 use prost::Message;
 use rand::Rng;
 use serde::Deserialize;
+use termcolor::Ansi;
+use termcolor::Color;
+use termcolor::ColorSpec;
+use termcolor::WriteColor;
 use tokio::sync::watch;
 use url::Url;
 use uuid::Uuid;
@@ -272,12 +278,28 @@ impl<P: RemoteDbHandlerPermissions> Database for RemoteDb<P> {
     &self,
     _state: Rc<RefCell<OpState>>,
   ) -> Result<Self::QMH, AnyError> {
+    let msg = "Deno.Kv.listenQueue is not supported for remote KV databases";
+    eprintln!("{}", yellow(msg));
     deno_core::futures::future::pending().await
   }
 
   fn close(&self) {}
 }
 
+fn yellow<S: AsRef<str>>(s: S) -> impl fmt::Display {
+  if std::env::var_os("NO_COLOR").is_some() {
+    return String::from(s.as_ref());
+  }
+  let mut style_spec = ColorSpec::new();
+  style_spec.set_fg(Some(Color::Yellow));
+  let mut v = Vec::new();
+  let mut ansi_writer = Ansi::new(&mut v);
+  ansi_writer.set_color(&style_spec).unwrap();
+  ansi_writer.write_all(s.as_ref().as_bytes()).unwrap();
+  ansi_writer.reset().unwrap();
+  String::from_utf8_lossy(&v).into_owned()
+}
+
 fn decode_value(
   value: Vec<u8>,
   encoding: pb::KvValueEncoding,