Add Diagnostic provider to Schema Validation, improve JSON Pointer handling and add Dialect support

language-server/package.json

@@ -20,6 +20,7 @@
   "keywords": [],
   "dependencies": {
     "@hyperjump/json-schema": "^1.17.6",
+    "@hyperjump/json-schema-errors": "github:hyperjump-io/json-schema-errors",
     "jsonc-parser": "^3.3.1",
     "merge-anything": "^6.0.6",
     "vscode-languageserver": "^10.0.0",

language-server/src/build-server.ts

@@ -1,9 +1,14 @@
 import "@hyperjump/json-schema/draft-2020-12";
+import "@hyperjump/json-schema/draft-2019-09";
+import "@hyperjump/json-schema/draft-07";
+import "@hyperjump/json-schema/draft-06";
+import "@hyperjump/json-schema/draft-04";
 import { TextDocuments } from "vscode-languageserver";
 import { TextDocument } from "vscode-languageserver-textdocument";
 import { Server } from "./services/server.ts";
 import { Diagnostics } from "./features/Diagnostics.ts";
 import { SyntaxValidation } from "./features/SyntaxValidation.ts";
+import { SchemaValidation } from "./features/SchemaValidation.ts";
 
 import type { Connection } from "vscode-languageserver";
 
@@ -17,7 +22,8 @@ export const buildServer = (connection: Connection): Connection => {
   documents.listen(server);
 
   new Diagnostics(server, documents, [
-    new SyntaxValidation()
+    new SyntaxValidation(),
+    new SchemaValidation()
   ]);
 
   return server;

language-server/src/features/Diagnostics.ts

@@ -5,7 +5,7 @@ import { Server } from "../services/server.ts";
 import type { ServerCapabilities, Diagnostic } from "vscode-languageserver";
 
 export type DiagnosticsProvider = {
-  getDiagnostics(textDocument: TextDocument): Diagnostic[];
+  getDiagnostics(textDocument: TextDocument): Promise<Diagnostic[]>;
 };
 
 export class Diagnostics {
@@ -27,7 +27,7 @@ export class Diagnostics {
     documents.onDidChangeContent(async (change) => {
       const diagnostics = [];
       for (const provider of this.providers) {
-        diagnostics.push(...provider.getDiagnostics(change.document));
+        diagnostics.push(...await provider.getDiagnostics(change.document));
       }
 
       await server.sendDiagnostics({

language-server/src/features/SchemaValidation.ts

@@ -0,0 +1,67 @@
+import { Diagnostic, DiagnosticSeverity } from "vscode-languageserver";
+import { TextDocument } from "vscode-languageserver-textdocument";
+import * as jsonc from "jsonc-parser";
+import { validate } from "@hyperjump/json-schema-errors";
+import { pointerSegments } from "@hyperjump/json-pointer";
+
+import type { ErrorObject } from "@hyperjump/json-schema-errors";
+import type { DiagnosticsProvider } from "./Diagnostics.ts";
+
+export class SchemaValidation implements DiagnosticsProvider {
+  async getDiagnostics(textDocument: TextDocument) {
+    const text = textDocument.getText();
+    const parseErrors: jsonc.ParseError[] = [];
+
+    const tree = jsonc.parseTree(text, parseErrors);
+    const schemaDiagnostics: Diagnostic[] = [];
+
+    const schemaNode = tree ? jsonc.findNodeAtLocation(tree, ["$schema"]) : undefined;
+    const schemaUri = schemaNode?.value;
+
+    // skip schema validation if there are syntax errors hence the parseError.length check
+    if (schemaUri && parseErrors.length === 0) {
+      let instance = JSON.parse(text);
+      const result = await validate(schemaUri, instance);
+
+      if (!result.valid) {
+        const errors = result.errors;
+        errors.forEach((error) => {
+          const node = tree ? findNodeByPointer(tree, error.instanceLocation) : undefined;
+
+          if (node) {
+            schemaDiagnostics.push({
+              severity: DiagnosticSeverity.Error,
+              range: {
+                start: textDocument.positionAt(node.offset),
+                end: textDocument.positionAt(node.offset + node.length)
+              },
+              message: formatError(error),
+              source: "json-language-server"
+            });
+          }
+        });
+      }
+    }
+
+    return schemaDiagnostics;
+  }
+}
+
+const findNodeByPointer = (node: jsonc.Node, pointer: string) => {
+  if (pointer === "#") {
+    return node;
+  }
+  const segments = [...pointerSegments(pointer.slice(1))];
+  const path = segments.map((s) => /^\d+$/.test(s) ? parseInt(s) : s);
+  return jsonc.findNodeAtLocation(node, path);
+};
+
+const formatError = (error: ErrorObject, depth = 0): string => {
+  let msg = error.message;
+  if (error.alternatives && error.alternatives.length > 0) {
+    const indent = "  ".repeat(depth + 1);
+    const lines = error.alternatives.flatMap((alt) => alt.map((subErr) => `${indent}- ${formatError(subErr, depth + 1)}`));
+    msg += `:\n${lines.join("\n")}`;
+  }
+  return msg;
+};

language-server/src/features/SyntaxValidation.ts

@@ -1,11 +1,11 @@
-import { Diagnostic, DiagnosticSeverity } from "vscode-languageserver";
+import { DiagnosticSeverity } from "vscode-languageserver";
 import { TextDocument } from "vscode-languageserver-textdocument";
 import * as jsonc from "jsonc-parser";
 
 import type { DiagnosticsProvider } from "./Diagnostics.ts";
 
 export class SyntaxValidation implements DiagnosticsProvider {
-  getDiagnostics(textDocument: TextDocument): Diagnostic[] {
+  async getDiagnostics(textDocument: TextDocument) {
     const text = textDocument.getText();
     const parseErrors: jsonc.ParseError[] = [];