Slightly better error handling

ibkr.py

@@ -27,32 +27,36 @@ def get_positions(self):
         account_id = client.portfolio_accounts().data[0]['id']
         full_positions = client.positions(account_id = account_id).data
 
-        marketdata_fields = {
-            '31': 'lastPrice',
-            '80': 'unrealizedPnlPercent',
-            '78': 'dailyPnl',
-        }
-        client.portfolio_accounts()
-        marketdata = client.live_marketdata_snapshot(
-            conids = [ str(item['conid']) for item in full_positions ],
-            fields = list(marketdata_fields.keys())
-        ).data
-
-        marketdata_fields['conid'] = 'conid'
-        processed_marketdata = [
-            { marketdata_fields[key]: value for key, value in item.items() if key in marketdata_fields }
-            for item in marketdata
-        ]
-
         positions_fields = [ 'avgCost', 'conid', 'ticker', 'name', 'unrealizedPnl', 'mktValue' ]
         positions = [
             { k: v for k, v in d.items() if k in positions_fields }
             for d in full_positions
         ]
 
-        merged = [
-            { **pos, **next(md for md in processed_marketdata if md['conid'] == pos['conid']) }
-            for pos in positions
-        ]
+        marketdata_fields = {
+            '31': 'lastPrice',
+            '80': 'unrealizedPnlPercent',
+            '78': 'dailyPnl',
+        }
 
-        return [ self.clean(row) for row in merged ]
+        try:
+            client.portfolio_accounts()
+            marketdata = client.live_marketdata_snapshot(
+                conids = [ str(item['conid']) for item in full_positions ],
+                fields = list(marketdata_fields.keys())
+            ).data
+
+            marketdata_fields['conid'] = 'conid'
+            processed_marketdata = [
+                { marketdata_fields[key]: value for key, value in item.items() if key in marketdata_fields }
+                for item in marketdata
+            ]
+
+            merged = [
+                { **pos, **next(md for md in processed_marketdata if md['conid'] == pos['conid']) }
+                for pos in positions
+            ]
+
+            return [ self.clean(row) for row in merged ]
+        except Exception:
+            return positions

main.py

@@ -1,11 +1,17 @@
-from fastapi import FastAPI
+from fastapi import FastAPI, HTTPException
 from fastapi.staticfiles import StaticFiles
 from ibkr import Ibkr
+import traceback
+import sys
 
 app = FastAPI()
 
 @app.get("/positions")
 async def positions():
-    return Ibkr().get_positions()
+    try:
+        return Ibkr().get_positions()
+    except Exception:
+        exc_info = sys.exc_info()
+        raise HTTPException(status_code=500, detail=''.join(traceback.format_exception(*exc_info)))
 
 app.mount("/", StaticFiles(directory="static", html = True), name="static")

static/main.js

@@ -2,7 +2,7 @@ import { render } from 'preact';
 import { useState, useEffect } from 'preact/hooks';
 import { html } from 'htm/preact';
 
-const formatNumber = (input) => input.toLocaleString('en-US', {
+const formatNumber = (input) => !input ? '' : input.toLocaleString('en-US', {
     minimumFractionDigits: 2,
     maximumFractionDigits: 2,
 });
@@ -93,6 +93,7 @@ const Main = () => {
     const [ data, setData ] = useState([]);
     const [ summary, setSummary ] = useState({});
     const [ sort, setSort ] = useState({ field: 'changePercent', order: 'desc' });
+    const [ error, setError ] = useState('');
 
     useEffect(() => {
         fetch('positions')
@@ -103,7 +104,7 @@ const Main = () => {
                 throw Error(await response.text());
             })
             .then((response) => setData(sortData(response, sort.field, sort.order)))
-            .catch((e) => console.error(e));
+            .catch((e) => setError(e.message));
     }, []);
 
     useEffect(() => {
@@ -128,13 +129,13 @@ const Main = () => {
         setData(sortData(data, sort.field, sort.order));
     }, [ sort ]);
 
-    return data.length === 0 ? 'Loading..' : html`
+    return error || (!data.length ? 'Loading..' : html`
         <div class="table">
             <${Headers} sort=${sort} setSort=${setSort} />
             <${DataRows} data=${data} />
             <${SummaryTow} summary=${summary} />
         </div>
-    `;
+    `);
 };
 
 render(html`<${Main} />`, document.getElementById('root'));