notify user when existing audits are reused in chain

editor-plugin/src/commands.ts

@@ -80,10 +80,26 @@ export function registerCommands(context: vscode.ExtensionContext) {
     context.subscriptions.push(
         vscode.commands.registerCommand('cargo-scan.create_chain', async () => {
             client.sendRequest('cargo-scan.create_chain');
+
+            client.onNotification('cargo-scan.info', (message: string) => {                
+                vscode.window.showInformationMessage(
+                message, 
+                'View Logs',
+                // 'Settings'
+                ).then(selection => {
+                    if (selection === 'View Logs') {
+                        client.outputChannel.show();
+                    }
+                    // else if (selection === 'Settings') {
+                    //     vscode.commands.executeCommand('workbench.action.openSettings', '@ext:PLsysSec.cargo-scan');
+                    // }
+                });
+            });
+
             context.globalState.update('annotateEffects', false);
             context.globalState.update('chainAudit', false);
             locationsProvider.clear();
-            annotations.clear();         
+            annotations.clear();      
         })
     );
 

lang_server/src/server.rs

@@ -64,6 +64,16 @@ impl Request for CallerCheckedCommand {
     const METHOD: &'static str = "cargo-scan.get_callers";
 }
 
+#[derive(Debug, Serialize, Deserialize)]
+struct InfoMessageParams {
+    pub message: String,
+}
+
+impl Notification for InfoMessageParams {
+    const METHOD: &'static str = "cargo-scan.info";
+    type Params = InfoMessageParams;
+}
+
 pub fn run_server() -> anyhow::Result<(), Box<dyn Error + Sync + Send>> {
     let (connection, io_threads) = Connection::stdio();
 
@@ -190,10 +200,23 @@ fn runner(
                         let create_args = Create {
                             crate_path: root_crate_path.to_string_lossy().to_string(),
                             manifest_path: chain_manifest.to_string_lossy().to_string(),
-                            force_overwrite: true,
                             ..Default::default()
                         };
 
+                        if !create_args.force_overwrite {
+                            let params = InfoMessageParams {
+                                message: "May reuse existing audits for chain"
+                                    .to_string(),
+                            };
+                            let value = serde_json::to_value(params.message)?;
+                            let notification =
+                                Message::Notification(lsp_server::Notification {
+                                    method: InfoMessageParams::METHOD.to_string(),
+                                    params: value,
+                                });
+                            conn.sender.send(notification)?;
+                        }
+
                         CommandRunner::run_command(
                             Command::Create(create_args),
                             outer_args,

src/audit_chain.rs

@@ -479,10 +479,23 @@ fn make_new_audit_file(
         if args.force_overwrite {
             remove_file(audit_file_path.clone())?;
         } else {
-            return Err(anyhow!("Audit file already exists"));
+            info!(
+                "Using existing audit for {} v{} ({})",
+                package.name,
+                package.version,
+                audit_file_path.display()
+            );
+            let audit_file = AuditFile::read_audit_file(audit_file_path.clone())?
+                .ok_or_else(|| {
+                    anyhow!("Couldn't read audit: {}", audit_file_path.display())
+                })?;
+            chain.add_crate_audit_file(package, audit_file_path, audit_file.version);
+
+            return Ok(());
         }
     }
 
+    info!("Making default audit for {} v{}", package.name, package.version);
     let sinks = collect_dependency_sinks(chain, &package.dependencies)?;
     let audit_file = AuditFile::new_default_with_sinks(
         &package_path,
@@ -539,7 +552,6 @@ pub fn create_new_audit_chain(
     let mut traverse = DfsPostOrder::new(&graph, root_node);
     while let Some(node) = traverse.next(&graph) {
         let package = package_map.get(&node).unwrap();
-        info!("Making default audit for {} v{}", package.name, package.version);
 
         let audit_type = if node == root_node {
             DefaultAuditType::Empty