fix(linux): repair CUPS queue usability for Chromium

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@fieldlens/print",
-  "version": "0.1.5",
+  "version": "0.1.6",
   "private": true,
   "type": "module",
   "scripts": {

src-tauri/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "fieldlens-print"
-version = "0.1.5"
+version = "0.1.6"
 description = "FieldLens print-stream barcode capture companion"
 authors = ["Arrowstack"]
 edition = "2021"

src-tauri/src/printers.rs

@@ -52,6 +52,11 @@ pub fn list_system_printers() -> Result<Vec<SystemPrinter>> {
 }
 
 pub fn virtual_printer_status() -> Result<VirtualPrinterStatus> {
+    #[cfg(target_os = "linux")]
+    {
+        return linux_virtual_printer_status();
+    }
+
     let installed = list_system_printers()?
         .iter()
         .any(|printer| is_virtual_printer_name(&printer.name));
@@ -270,6 +275,13 @@ fn list_linux_printers() -> Result<Vec<SystemPrinter>> {
         let Some((name, uri)) = rest.split_once(": ") else {
             continue;
         };
+        // Ignore placeholder/dummy queues. They can expose a PPD but are not a
+        // usable physical destination and can make Chromium reject the cloned
+        // FieldLens queue as "not installed correctly".
+        if uri == "///dev/null" || uri == "file:///dev/null" {
+            continue;
+        }
+
         let address = socket_uri_to_address(uri);
         printers.push(SystemPrinter {
             name: name.to_string(),
@@ -296,6 +308,67 @@ fn socket_uri_to_address(uri: &str) -> Option<String> {
     }
 }
 
+#[cfg(target_os = "linux")]
+fn linux_virtual_printer_status() -> Result<VirtualPrinterStatus> {
+    let printers = list_linux_printers()?;
+    let installed = printers
+        .iter()
+        .any(|printer| is_virtual_printer_name(&printer.name));
+
+    if !installed {
+        return Ok(VirtualPrinterStatus {
+            installed: false,
+            name: VIRTUAL_PRINTER_NAME.into(),
+            detail: "Not installed yet. Choose the physical destination printer, then create it.".into(),
+        });
+    }
+
+    let state = Command::new("lpstat")
+        .args(["-p", "FieldLens-Print"])
+        .output()
+        .context("query FieldLens Print CUPS state")?;
+    let accepting = Command::new("lpstat")
+        .args(["-a", "FieldLens-Print"])
+        .output()
+        .context("query FieldLens Print accepting state")?;
+
+    let state_text = String::from_utf8_lossy(&state.stdout);
+    let accepting_text = String::from_utf8_lossy(&accepting.stdout);
+    let enabled = state.status.success()
+        && !state_text.to_ascii_lowercase().contains("disabled");
+    let accepts_jobs = accepting.status.success()
+        && accepting_text.to_ascii_lowercase().contains("accepting requests");
+    let ready = enabled && accepts_jobs;
+
+    Ok(VirtualPrinterStatus {
+        installed: ready,
+        name: VIRTUAL_PRINTER_NAME.into(),
+        detail: if ready {
+            "Ready and accepting jobs in the system print dialog.".into()
+        } else {
+            "FieldLens Print exists but CUPS has it disabled or not accepting jobs. Click Create / repair FieldLens Print.".into()
+        },
+    })
+}
+
+#[cfg(target_os = "linux")]
+fn run_cups_repair_command(program: &str, args: &[&str]) -> Result<()> {
+    let direct = Command::new(program).args(args).status();
+    if matches!(direct, Ok(status) if status.success()) {
+        return Ok(());
+    }
+
+    let status = Command::new("pkexec")
+        .arg(program)
+        .args(args)
+        .status()
+        .with_context(|| format!("run elevated {program}"))?;
+    if !status.success() {
+        return Err(anyhow!("{program} failed; administrator approval may be required"));
+    }
+    Ok(())
+}
+
 #[cfg(target_os = "linux")]
 fn install_linux_virtual_printer(target_printer: &str) -> Result<()> {
     let printers = list_linux_printers()?;
@@ -326,10 +399,7 @@ fn install_linux_virtual_printer(target_printer: &str) -> Result<()> {
     args.push(VIRTUAL_PRINTER_NAME.to_string());
 
     let direct = Command::new("lpadmin").args(&args).status();
-    if matches!(direct, Ok(status) if status.success()) {
+    if !matches!(direct, Ok(status) if status.success()) {
-        return Ok(());
-    }
-
         let status = Command::new("pkexec")
             .arg("lpadmin")
             .args(&args)
@@ -341,6 +411,12 @@ fn install_linux_virtual_printer(target_printer: &str) -> Result<()> {
                 "CUPS printer setup failed; administrator approval may be required"
             ));
         }
+    }
+
+    // lpadmin -E normally enables the queue, but explicitly repair both CUPS
+    // state flags because Chromium disables Print when either is stale.
+    run_cups_repair_command("cupsenable", &["FieldLens-Print"])?;
+    run_cups_repair_command("cupsaccept", &["FieldLens-Print"])?;
     Ok(())
 }
 

src-tauri/tauri.conf.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://schema.tauri.app/config/2",
   "productName": "FieldLens Print",
-  "version": "0.1.5",
+  "version": "0.1.6",
   "identifier": "dev.arrowstack.fieldlens.print",
   "build": {
     "beforeDevCommand": "npm run dev",

src/main.ts

@@ -85,7 +85,7 @@ let config: AppConfig
 let jobs: Job[] = []
 let status: Status
 let loginTimer: number | undefined
-let currentVersion = '0.1.5'
+let currentVersion = '0.1.6'
 let bundleType: BundleType | null = null
 let availableUpdate: Update | null = null
 let availableManualUpdate: ManualUpdate | null = null