Implement missing sample data loading and one-time use security

- Fix UI to load server-hosted sample data at startup as per specification
- Add one-time use security: server clears sample data after retrieval
- Ensure React app periodically checks for new sample data availability
- Remove complex same-origin protection in favor of simpler one-time use model
- Improve data security by preventing data persistence after consumption

bin/upload-jmespath

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+API_URL="https://jmespath-playground.koszewscy.waw.pl"
+JSON_FILE="-"
+
+function usage() {
+    echo "Usage: $0 [--api-url <url>] [--json-file <file>]"
+    exit 1
+}
+
+while [[ $# -gt 0 ]]; do
+    case $1 in
+        --api-url)
+            API_URL="$2"
+            shift 2
+            ;;
+        --json-file)
+            JSON_FILE="$2"
+            shift 2
+            ;;
+        -h|--help)
+            usage
+            exit 0
+            ;;
+        *)
+            echo "ERROR: Unknown argument: $1"
+            usage
+            exit 1
+            ;;
+    esac
+done
+
+# Send the POST request
+curl -s -X POST \
+    -H "Content-Type: application/json" \
+    -H "Accept: application/json" \
+    --data @${JSON_FILE} \
+    "$API_URL/api/v1/upload"
+

package.json

@@ -1,6 +1,6 @@
 {
   "name": "jmespath-playground",
-  "version": "1.1.6",
+  "version": "1.1.7",
   "description": "A React-based web application for testing JMESPath expressions against JSON data",
   "main": "index.js",
   "scripts": {

server.js

@@ -51,7 +51,13 @@ function createApp() {
 
   app.get('/api/v1/sample', (req, res) => {
     try {
-      res.json(sampleData);
+      const dataToReturn = sampleData;
+
+      // Security: Clear the sample data after it's retrieved (one-time use)
+      sampleData = null;
+      console.log('📤 Sample data retrieved and cleared from server memory');
+
+      res.json(dataToReturn);
     } catch (error) {
       res.status(500).json({ error: 'Failed to retrieve sample data' });
     }

src/App.js

@@ -54,22 +54,30 @@ function App() {
     localStorage.setItem('theme', theme);
   }, [theme]);
 
-  // API polling for state changes
+  // API polling for state changes and initial sample data load
   useEffect(() => {
-    // Initial state load
-    const loadInitialState = async () => {
+    // Initial load: get both state and sample data
+    const loadInitialData = async () => {
       try {
-        const response = await fetch('/api/v1/state');
-        if (response.ok) {
-          const data = await response.json();
-          setCurrentStateGuid(data.state);
+        // Load sample data first
+        const sampleResponse = await fetch('/api/v1/sample');
+        if (sampleResponse.ok) {
+          const sampleData = await sampleResponse.json();
+          setJsonData(JSON.stringify(sampleData, null, 2));
+        }
+
+        // Then load state GUID
+        const stateResponse = await fetch('/api/v1/state');
+        if (stateResponse.ok) {
+          const stateData = await stateResponse.json();
+          setCurrentStateGuid(stateData.state);
         }
       } catch (error) {
         console.debug('API not available:', error);
       }
     };
 
-    loadInitialState();
+    loadInitialData();
 
     // Poll for state changes every 3 seconds
     const interval = setInterval(async () => {