Complete Section: Frontend Blockchain

Author: 15Dkatz

README.md

@@ -37,4 +37,12 @@ export PEER=True && python3 -m backend.app
 In the frontend directory:
 ```
 npm run start
+```
+
+**Seed the backend with data**
+
+Make sure to activate the virtual environment.
+
+```
+export SEED_DATA=True && python3 -m backend.app
 ```

backend/app/__init__.py

@@ -26,6 +26,18 @@ def route_default():
 def route_blockchain():
     return jsonify(blockchain.to_json())
 
+@app.route('/blockchain/range')
+def route_blockchain_range():
+    # http://localhost:5000/blockchain/range?start=2&end=5
+    start = int(request.args.get('start'))
+    end = int(request.args.get('end'))
+
+    return jsonify(blockchain.to_json()[::-1][start:end])
+
+@app.route('/blockchain/length')
+def route_blockchain_length():
+    return jsonify(len(blockchain.chain))
+
 @app.route('/blockchain/mine')
 def route_blockchain_mine():
     transaction_data = transaction_pool.transaction_data()
@@ -78,4 +90,11 @@ def route_wallet_info():
     except Exception as e:
         print(f'\n -- Error synchronizing: {e}')
 
+if os.environ.get('SEED_DATA') == 'True':
+    for i in range(10):
+        blockchain.add_block([
+            Transaction(Wallet(), Wallet().address, random.randint(2, 50)).to_json(),
+            Transaction(Wallet(), Wallet().address, random.randint(2, 50)).to_json()
+        ])
+
 app.run(port=PORT)

frontend/package-lock.json

@@ -4,6 +4,7 @@
   "private": true,
   "dependencies": {
     "react": "^16.10.2",
+    "react-bootstrap": "^1.0.0-beta.14",
     "react-dom": "^16.10.2",
     "react-scripts": "3.2.0"
   },