feat(congodb): implement CongoDB MongoDB wire-protocol compatible in-memory server and APIs

ts/congodb/server/handlers/InsertHandler.ts

@@ -0,0 +1,91 @@
+import * as plugins from '../../congodb.plugins.js';
+import type { ICommandHandler, IHandlerContext } from '../CommandRouter.js';
+
+/**
+ * InsertHandler - Handles insert commands
+ */
+export class InsertHandler implements ICommandHandler {
+  async handle(context: IHandlerContext): Promise<plugins.bson.Document> {
+    const { storage, database, command, documentSequences } = context;
+
+    const collection = command.insert;
+    if (typeof collection !== 'string') {
+      return {
+        ok: 0,
+        errmsg: 'insert command requires a collection name',
+        code: 2,
+        codeName: 'BadValue',
+      };
+    }
+
+    // Get documents from command or document sequences
+    let documents: plugins.bson.Document[] = command.documents || [];
+
+    // Check for OP_MSG document sequences (for bulk inserts)
+    if (documentSequences && documentSequences.has('documents')) {
+      documents = documentSequences.get('documents')!;
+    }
+
+    if (!Array.isArray(documents) || documents.length === 0) {
+      return {
+        ok: 0,
+        errmsg: 'insert command requires documents array',
+        code: 2,
+        codeName: 'BadValue',
+      };
+    }
+
+    const ordered = command.ordered !== false;
+    const writeErrors: plugins.bson.Document[] = [];
+    let insertedCount = 0;
+
+    // Ensure collection exists
+    await storage.createCollection(database, collection);
+
+    // Insert documents
+    for (let i = 0; i < documents.length; i++) {
+      const doc = documents[i];
+
+      try {
+        // Ensure _id exists
+        if (!doc._id) {
+          doc._id = new plugins.bson.ObjectId();
+        }
+
+        await storage.insertOne(database, collection, doc);
+        insertedCount++;
+      } catch (error: any) {
+        const writeError: plugins.bson.Document = {
+          index: i,
+          code: error.code || 11000,
+          errmsg: error.message || 'Insert failed',
+        };
+
+        // Check for duplicate key error
+        if (error.message?.includes('Duplicate key')) {
+          writeError.code = 11000;
+          writeError.keyPattern = { _id: 1 };
+          writeError.keyValue = { _id: doc._id };
+        }
+
+        writeErrors.push(writeError);
+
+        if (ordered) {
+          // Stop on first error for ordered inserts
+          break;
+        }
+      }
+    }
+
+    const response: plugins.bson.Document = {
+      ok: 1,
+      n: insertedCount,
+    };
+
+    if (writeErrors.length > 0) {
+      response.writeErrors = writeErrors;
+    }
+
+    return response;
+  }
+}