CSV import: explicit column-to-property mapping

.gitignore

@@ -1,3 +1,4 @@
 copilot/
 tools/
 infra/.env
+.DS_Store

app/packages/language-csv/package.json

@@ -0,0 +1,16 @@
+{
+    "name": "@mdeo/language-csv",
+    "version": "0.1.0",
+    "type": "module",
+    "main": "dist/index.js",
+    "types": "dist/index.d.ts",
+    "files": ["dist", "src"],
+    "dependencies": {
+        "@mdeo/language-common": "^0.1.0",
+        "@mdeo/language-shared": "^0.1.0"
+    },
+    "devDependencies": {
+        "@types/node": "^25.3.1",
+        "langium": "^4.2.1"
+    }
+}

app/packages/language-csv/src/csvPlugin.ts

@@ -0,0 +1,39 @@
+import {
+    type LangiumLanguagePlugin,
+    type LangiumLanguagePluginProvider,
+    type LanguageServices,
+    type ExternalReferenceAdditionalServices
+} from "@mdeo/language-common";
+import {
+    DefaultAstSerializer,
+    SerializerFormatter,
+    registerDefaultTokenSerializers,
+    DefaultExternalReferenceCollector
+} from "@mdeo/language-shared";
+import type { ServerContributionPlugin } from "@mdeo/plugin";
+import { CsvFileRule, CsvTerminals } from "./grammar/csvRules.js";
+
+function createCsvPlugin(): LangiumLanguagePlugin<ExternalReferenceAdditionalServices> {
+    return {
+        rootRule: CsvFileRule,
+        additionalTerminals: CsvTerminals,
+        module: {
+            references: {
+                ExternalReferenceCollector: () => new DefaultExternalReferenceCollector()
+            },
+            lsp: {
+                Formatter: (services: LanguageServices & ExternalReferenceAdditionalServices) => new SerializerFormatter(services)
+            },
+            AstSerializer: (services: LanguageServices & ExternalReferenceAdditionalServices) => new DefaultAstSerializer(services)
+        },
+        postCreate(services: LanguageServices & ExternalReferenceAdditionalServices) {
+            registerDefaultTokenSerializers(services);
+        }
+    };
+}
+
+export const csvPluginProvider: LangiumLanguagePluginProvider<ExternalReferenceAdditionalServices> = {
+    create(_contributionPlugins: ServerContributionPlugin[], _languageJsUrl?: string): LangiumLanguagePlugin<ExternalReferenceAdditionalServices> {
+        return createCsvPlugin();
+    }
+};

app/packages/language-csv/src/grammar/csvRules.ts

@@ -0,0 +1,19 @@
+import { createTerminal, createRule, optional, WS } from "@mdeo/language-common";
+import { CsvFile } from "./csvTypes.js";
+
+/**
+ * Matches a whole CSV file as one token. The CSV language does no structural
+ * parsing of its own, the content is interpreted where it is imported.
+ *
+ * The pattern requires at least one character, since a terminal that can match
+ * the empty string would never advance the lexer. An empty file is handled by
+ * making the assignment optional in the rule below rather than by allowing an
+ * empty match here.
+ */
+export const ANY_TEXT = createTerminal("ANY_TEXT").as(/[\s\S]+/);
+
+export const CsvFileRule = createRule("CsvFileRule")
+    .returns(CsvFile)
+    .as(({ set }) => [optional(set("content", ANY_TEXT))]);
+
+export const CsvTerminals = [WS, ANY_TEXT];

app/packages/language-csv/src/grammar/csvTypes.ts

@@ -0,0 +1,15 @@
+import { createInterface, Optional, type ASTType } from "@mdeo/language-common";
+
+/**
+ * A CSV file's contents, held as a single blob of text.
+ *
+ * `content` is optional because an empty file is a valid CSV file. The
+ * workbench offers a "Create New CSV" action, which produces an empty file, so
+ * requiring content would put every newly created CSV straight into a parse
+ * error state.
+ */
+export const CsvFile = createInterface("CsvFile").attrs({
+    content: Optional(String)
+});
+
+export type CsvFileType = ASTType<typeof CsvFile>;

app/packages/language-csv/src/index.ts

@@ -0,0 +1,3 @@
+export * from "./grammar/csvTypes.js";
+export * from "./grammar/csvRules.js";
+export * from "./csvPlugin.js";

app/packages/language-csv/tsconfig.json

@@ -0,0 +1,13 @@
+{
+    "extends": "../../tsconfig.json",
+    "compilerOptions": {
+        "rootDir": "src",
+        "outDir": "dist",
+        "composite": true
+    },
+    "include": ["src"],
+    "references": [
+        { "path": "../language-common" },
+        { "path": "../language-shared" }
+    ]
+}

app/packages/language-model-csv/package.json

@@ -0,0 +1,18 @@
+{
+    "name": "@mdeo/language-model-csv",
+    "version": "0.1.0",
+    "type": "module",
+    "main": "dist/index.js",
+    "types": "dist/index.d.ts",
+    "files": ["dist", "src"],
+    "dependencies": {
+        "@mdeo/language-common": "^0.1.0",
+        "@mdeo/language-model": "^0.1.0",
+        "@mdeo/language-metamodel": "^0.1.0",
+        "@mdeo/language-shared": "^0.1.0"
+    },
+    "devDependencies": {
+        "@types/node": "^25.3.1",
+        "langium": "^4.2.1"
+    }
+}

app/packages/language-model-csv/src/csvPlugin.ts

@@ -0,0 +1,90 @@
+import {
+    type LangiumLanguagePlugin,
+    type LangiumLanguagePluginProvider,
+    type ExternalReferenceAdditionalServices,
+    GrammarDeserializationContext,
+    ID,
+    NEWLINE,
+    HIDDEN_NEWLINE,
+    INT,
+    FLOAT,
+    STRING
+} from "@mdeo/language-common";
+import {
+    DefaultAstSerializer,
+    IdValueConverter,
+    SerializerFormatter,
+    registerDefaultTokenSerializers,
+    NewlineAwareTokenBuilder,
+    addExternalReferenceCollectionPhase,
+    ActionHandlerRegistry,
+    type ActionHandlerRegistryAdditionalServices,
+    DefaultActionProvider
+} from "@mdeo/language-shared";
+import { generateModelContributionGrammar, ModelTerminals, ModelScopeProvider, ModelExternalReferenceCollector } from "@mdeo/language-model";
+import { Class } from "@mdeo/language-metamodel";
+import { createModelCsvContributionPlugin } from "./plugin/modelCsvContributionPlugin.js";
+
+/**
+ * Combined services type for the standalone model-csv language.
+ * Reuses the base Model language's services, since the standalone grammar's
+ * root is a real `Model` node (an `import` line plus the CSV import block).
+ */
+export type ModelCsvServices = ExternalReferenceAdditionalServices & ActionHandlerRegistryAdditionalServices;
+
+/**
+ * Deserialization context for the CSV grammar.
+ * Provides the external interface types and common terminals so the CSV
+ * grammar can be deserialized from its serialized form.
+ */
+const csvDeserializationContext = GrammarDeserializationContext.create([Class], [], [ID, NEWLINE, HIDDEN_NEWLINE, INT, FLOAT, STRING]);
+
+/**
+ * The root rule for the standalone model-csv language.
+ * Generated from the CSV contribution plugin's grammar.
+ */
+const csvRootRule = generateModelContributionGrammar(createModelCsvContributionPlugin(), csvDeserializationContext);
+
+/**
+ * The plugin for the standalone model-csv generated language.
+ * Its root type is a real `Model` node, so it reuses the base Model language's
+ * own scope provider and external reference collector directly.
+ */
+const modelCsvPlugin: LangiumLanguagePlugin<ModelCsvServices> = {
+    rootRule: csvRootRule,
+    additionalTerminals: ModelTerminals,
+    module: {
+        parser: {
+            TokenBuilder: () => new NewlineAwareTokenBuilder(new Set(["{"]), new Set(["("]), new Set(["}", ")"])),
+            ValueConverter: () => new IdValueConverter(),
+            ParserConfig: () => ({
+                maxLookahead: 4
+            })
+        },
+        references: {
+            ScopeProvider: (services) => new ModelScopeProvider(services),
+            ExternalReferenceCollector: () => new ModelExternalReferenceCollector()
+        },
+        lsp: {
+            Formatter: (services) => new SerializerFormatter(services)
+        },
+        AstSerializer: (services) => new DefaultAstSerializer(services),
+        action: {
+            ActionHandlerRegistry: () => new ActionHandlerRegistry(),
+            ActionProvider: () => new DefaultActionProvider()
+        }
+    },
+    postCreate(services) {
+        registerDefaultTokenSerializers(services);
+        addExternalReferenceCollectionPhase(services);
+    }
+};
+
+/**
+ * Provider for the standalone model-csv language plugin.
+ */
+export const modelCsvPluginProvider: LangiumLanguagePluginProvider<ModelCsvServices> = {
+    create(): LangiumLanguagePlugin<ModelCsvServices> {
+        return modelCsvPlugin;
+    }
+};