Merge pull request #3705 from canonical/improve-cloud-init-errors

Improve cloud-init error messages
canonical · Oct 10, 2024 · 6dd1800 · 6dd1800
2 parents 950779c + 144e09e
commit 6dd1800
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Showing 2 changed files with 27 additions and 14 deletions.
diff --git a/src/client/cli/cmd/launch.cpp b/src/client/cli/cmd/launch.cpp
@@ -378,36 +378,41 @@ mp::ParseCode cmd::Launch::parse_args(mp::ArgParser* parser)
 
     if (parser->isSet(cloudInitOption))
     {
+        constexpr auto err_msg_template = "Could not load cloud-init configuration: {}";
         try
         {
+            const QString& cloud_init_file = parser->value(cloudInitOption);
             YAML::Node node;
-            const QString& cloudInitFile = parser->value(cloudInitOption);
-            if (cloudInitFile == "-")
+            if (cloud_init_file == "-")
             {
                 node = YAML::Load(term->read_all_cin());
             }
-            else if (cloudInitFile.startsWith("http://") || cloudInitFile.startsWith("https://"))
+            else if (cloud_init_file.startsWith("http://") || cloud_init_file.startsWith("https://"))
             {
                 URLDownloader downloader{std::chrono::minutes{1}};
-                auto downloaded_yaml = downloader.download(QUrl(cloudInitFile));
+                auto downloaded_yaml = downloader.download(QUrl(cloud_init_file));
                 node = YAML::Load(downloaded_yaml.toStdString());
             }
             else
             {
-                auto file_type = fs::status(cloudInitFile.toStdString()).type();
+                auto cloud_init_file_stdstr = cloud_init_file.toStdString();
+                auto file_type = fs::status(cloud_init_file_stdstr).type();
                 if (file_type != fs::file_type::regular && file_type != fs::file_type::fifo)
-                {
-                    cerr << "error: No such file: " << cloudInitFile.toStdString() << "\n";
-                    return ParseCode::CommandLineError;
-                }
+                    throw YAML::BadFile{cloud_init_file_stdstr};
 
-                node = YAML::LoadFile(cloudInitFile.toStdString());
+                node = YAML::LoadFile(cloud_init_file_stdstr);
             }
             request.set_cloud_init_user_data(YAML::Dump(node));
         }
-        catch (const std::exception& e)
+        catch (const YAML::BadFile& e)
+        {
+            auto err_detail = fmt::format("{}\n{}", e.what(), "Please ensure that Multipass can read it.");
+            fmt::println(cerr, err_msg_template, err_detail);
+            return ParseCode::CommandLineError;
+        }
+        catch (const YAML::Exception& e)
         {
-            cerr << "error loading cloud-init config: " << e.what() << "\n";
+            fmt::println(cerr, err_msg_template, e.what());
             return ParseCode::CommandLineError;
         }
     }

diff --git a/tests/test_cli_client.cpp b/tests/test_cli_client.cpp
@@ -1097,17 +1097,25 @@ TEST_F(Client, launch_cmd_cloudinit_option_with_valid_file_is_ok)
     EXPECT_THAT(send_command({"launch", "--cloud-init", qPrintable(tmpfile.fileName())}), Eq(mp::ReturnCode::Ok));
 }
 
-TEST_F(Client, launch_cmd_cloudinit_option_fails_with_missing_file)
+struct BadCloudInitFile : public Client, WithParamInterface<std::string>
+{
+};
+
+TEST_P(BadCloudInitFile, launch_cmd_cloudinit_option_fails_with_missing_file)
 {
     std::stringstream cerr_stream;
     auto missing_file{"/definitely/missing-file"};
 
     EXPECT_THAT(send_command({"launch", "--cloud-init", missing_file}, trash_stream, cerr_stream),
                 Eq(mp::ReturnCode::CommandLineError));
-    EXPECT_NE(std::string::npos, cerr_stream.str().find("No such file")) << "cerr has: " << cerr_stream.str();
+    EXPECT_NE(std::string::npos, cerr_stream.str().find("Could not load")) << "cerr has: " << cerr_stream.str();
     EXPECT_NE(std::string::npos, cerr_stream.str().find(missing_file)) << "cerr has: " << cerr_stream.str();
 }
 
+INSTANTIATE_TEST_SUITE_P(Client,
+                         BadCloudInitFile,
+                         Values("/definitely/missing-file", "/dev/null", "/home", "/root/.bashrc"));
+
 TEST_F(Client, launch_cmd_cloudinit_option_fails_no_value)
 {
     EXPECT_THAT(send_command({"launch", "--cloud-init"}), Eq(mp::ReturnCode::CommandLineError));