Add a sample nodejs project for compiling Malloy

sample_compilers/README.md

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+# Sample Scripts
+
+A set of sample scripts for working with Malloy models.
+
+## Setup
+
+First, run `npm install`
+
+## compile_malloy_duckdb.js (node.js)
+
+A script to compile a Malloy model. Returns JSON containing either the compiled model or a list of compilation errors.
+
+```
+  $ npm run compile ../faa/flights.malloy
+```
+
+OR 
+
+```
+  $ node compile_malloy_duckdb.js ../faa/flights.malloy
+```
+
+

sample_compilers/compile_malloy_duckdb.js

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+/**
+ * compile_duckdb.js
+ *
+ * Usage:
+ *   node compile_duckdb.js <path-to-malloy-file>
+ *
+ * Arguments:
+ *   <path-to-malloy-file>   Path to a .malloy model file to compile.
+ *
+ * Example:
+ *   node compile_duckdb.js ../models/shapes.malloy
+ *
+ * This script will compile the given Malloy model using a DuckDB connection.
+ */
+/* eslint-disable no-console, no-process-exit */
+
+const fs = require('fs').promises;
+const path = require('path');
+
+const {SingleConnectionRuntime} = require('@malloydata/malloy');
+const {DuckDBConnection} = require('@malloydata/db-duckdb');
+
+async function setupDuckDb(workingDirectory) {
+  // Initialize DuckDB WASM connection
+  const duckdbConnection = new DuckDBConnection({
+    workingDirectory,
+  });
+  await duckdbConnection.init();
+  return duckdbConnection;
+}
+
+// Compile a Malloy model from text
+async function compileMalloyModel(connection, malloyModelText) {
+  const runtime = new SingleConnectionRuntime({connection});
+  // Try to compile the model
+  try {
+    const model = await runtime.loadModel(malloyModelText);
+    const materializedModel = await model.getModel();
+    return {
+      ok: true,
+      data: materializedModel,
+    };
+  } catch (e) {
+    return {
+      ok: false,
+      errors: e.problems,
+    };
+  }
+}
+
+async function run() {
+  const filePath = process.argv[2];
+  if (!filePath) {
+    return {
+      ok: false,
+      errors: [
+        'No Malloy file path provided.\n\nUsage: node compile_duckdb.js <path-to-malloy-file>',
+      ],
+    };
+  }
+  try {
+    const absolutePath = path.resolve(filePath);
+    const malloyModelText = await fs.readFile(absolutePath, 'utf8');
+    // Provide the working directory of the model so Malloy will resolve data files
+    // relative to the model and not to this script.
+    const workingDirectory = path.dirname(absolutePath);
+    const duckDbConnection = await setupDuckDb(workingDirectory);
+    const result = await compileMalloyModel(duckDbConnection, malloyModelText);
+    return result;
+  } catch (err) {
+    return {
+      ok: false,
+      errors: [err.message],
+    };
+  }
+}
+
+run().then(result => {
+  if (!result.ok) {
+    console.error(JSON.stringify(result, null, 2));
+    process.exit(1);
+  } else {
+    console.log({...result, message: 'Malloy model compiled successfully.'});
+  }
+});