historical ohlc support, edit tvWidget to enable.

src/charts/jBars.js

@@ -0,0 +1,107 @@
+export async function jBars (from, to, res) {
+
+    console.log('[jBars]: Method call', res, from, to);
+
+    var fromDate = new Date(from*1000);
+    var toDate = new Date(to*1000);
+    console.log("fromDate:", fromDate.toUTCString());
+    console.log("toDate:  ", toDate.toUTCString());
+
+    const contract = "0xC31E54c7a869B9FcBEcc14363CF510d1c41fa443";
+
+    // check parameters
+
+    if (res != "1D") throw Error("Only 1D resolution currently supported");
+
+    console.assert(fromDate.getUTCHours()   == 0, "hours should be zero");
+    console.assert(fromDate.getUTCMinutes() == 0, "minutes should be zero");
+    console.assert(fromDate.getUTCSeconds() == 0, "seconds should be zero");
+    console.assert(fromDate.getUTCMilliseconds() == 0, "milliseconds should be zero");
+
+    // Spoof data
+
+    var spoof;
+    {
+        const yr = "2022";
+        const mo = "01";
+        const url = `/ohlc/42161/${contract}/${res}/${yr}/${contract}-${res}-${yr}${mo}.json`
+        const response = await fetch(url);	
+        spoof = await response.json();
+    }
+
+    var bars = [];
+
+    for ( // Once around for each sample in from-to range
+        let iDate = fromDate,
+            // loop state
+            iMonth = -1,
+            iolhc = 0,
+            ohlc;
+        iDate < toDate;
+        iDate.setUTCDate(iDate.getUTCDate()+1)
+        ) {
+
+        let bar = undefined;
+
+        // Fetch one sample file as needed
+
+        if (iMonth != iDate.getUTCMonth()) {
+            const yr = iDate.getUTCFullYear();
+            const mo = String(iDate.getUTCMonth()+1).padStart(2, '0');
+            const url = `/ohlc/42161/${contract}/${res}/${yr}/${contract}-${res}-${yr}${mo}.json`
+            let response = await fetch(url);
+            if (response.ok) {
+                ohlc = await response.json();
+            } else {
+                ohlc = []; // no file, then empty data
+            }
+            iMonth = iDate.getUTCMonth();
+            iolhc = 0;
+        }
+
+        let ohlcDate = iolhc >= ohlc.length ? undefined : new Date(ohlc[iolhc][0]+'Z');
+
+        // no ohlc sample, insert a visible sample
+
+        if (ohlcDate == undefined) {
+            bar = {
+                time:  iDate.getTime(),
+                open:  50,
+                high:  50,
+                low:   0,
+                close: 0,
+            }
+        }
+        
+        // ohlc sample not for this time, insert invisible sample
+
+        else if ( iDate.getTime() != ohlcDate.getTime() ) {
+
+            bar = {
+                time:  iDate.getTime(),
+                // open:  100,
+                // high:  100,
+                // low:   0,
+                // close: 0,
+            }
+
+        // Copy ohlc sample
+
+        } else {
+            bar = {
+                time:  iDate.getTime(),
+                open:  ohlc[iolhc][1],
+                high:  ohlc[iolhc][2],
+                low:   ohlc[iolhc][3],
+                close: ohlc[iolhc][4],
+            }
+            iolhc++;
+        }
+
+        if (bar==undefined) throw "bar==undefined";
+        bars.push(bar);
+
+    }
+
+    return bars;
+}