Replace non-functional NOAA API with reading data from a text file

RobertMParker · Jul 24, 2023 · 3c8f605 · 3c8f605
1 parent c39a369
commit 3c8f605
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Showing 2 changed files with 36 additions and 26 deletions.
diff --git a/index.html b/index.html
@@ -99,7 +99,7 @@ <h2><a target="_blank" href='https://ambientweather.net/dashboard/0e02feb4d3f58c
 
   <h2><a target="_blank" href='https://www.ndbc.noaa.gov/station_page.php?station=46026'>Farallones Buoy</a></h2>
   <p>This buoy 20 miles off the coast of San Francisco can indicate future conditions.</p>
-  <canvas id="urn:ioos:station:wmo:46026" class="NOAAWind" timezone="PST8PDT" height="120"></canvas>
+  <canvas id="46026" class="NOAAWind" timezone="PST8PDT" height="120"></canvas>
 
   <h1>Webcams</h1>
 

diff --git a/noaa-wind.js b/noaa-wind.js
@@ -1,4 +1,4 @@
-// Class for getting measurements from sdf.ndbc.noaa.gov
+// Class for getting measurements from https://www.ndbc.noaa.gov/data/5day2/<station_id>_5day.txt
 
 class NOAAWind extends Wind {
   constructor(stationId, timezone) {
@@ -8,44 +8,54 @@ class NOAAWind extends Wind {
   }
 
   makeRequest() {
-    var startTime = moment().subtract(24, 'hours').format('YYYY-MM-DDTHH:mm[Z]');
-    var endTime = moment().format('YYYY-MM-DDTHH:mm[Z]');
-
-    // Make request to get JSON weather data for stationId
     this.xmlhttp = new XMLHttpRequest();
     this.xmlhttp.onreadystatechange = this.onResponseReceived.bind(this);
-    this.xmlhttp.open('GET', 'https://sdf.ndbc.noaa.gov/sos/server.php?request=GetObservation&service=SOS&version=1.0.0&offering=' + this.stationId + '&observedproperty=Winds&responseformat=text/csv&eventtime=' + startTime + '/' + endTime, true);
+    // Found this cors proxy randomly on Google, not sure if it's trustworthy
+    const url = 'https://corsproxy.io/?' + encodeURIComponent('https://www.ndbc.noaa.gov/data/5day2/' + this.stationId + '_5day.txt');
+    this.xmlhttp.open('GET', url, true);
     this.xmlhttp.send();
-
-    // fields:
-    // - 0 station_id
-    // - 1 sensor_id
-    // - 2 latitude (degree)
-    // - 3 longitude (degree)
-    // - 4 date_time
-    // - 5 depth (m)
-    // - 6 wind_from_direction (degree)
-    // - 7 wind_speed (m/s)
-    // - 8 wind_speed_of_gust (m/s)
-    // - 9 upward_air_velocity (m/s)
   }
 
   parseData() {
-    var response = Papa.parse(this.xmlhttp.responseText, { header: true });
+  /* Example response:
+#YY  MM DD hh mm WDIR WSPD GST  WVHT   DPD   APD MWD   PRES  ATMP  WTMP  DEWP  VIS PTDY  TIDE
+#yr  mo dy hr mn degT m/s  m/s     m   sec   sec degT   hPa  degC  degC  degC  nmi  hPa    ft
+2023 07 24 20 10 300  6.0  7.0    MM    MM    MM  MM 1020.2    MM  12.9    MM   MM   MM    MM
+2023 07 24 20 00 300  5.0  7.0    MM    MM    MM  MM 1020.3    MM  12.9    MM   MM +1.0    MM
+2023 07 24 19 50 300  5.0  7.0   1.4     7   5.2 304 1020.2    MM  12.9    MM   MM   MM    MM
+2023 07 24 19 40 310  6.0  8.0    MM    MM    MM  MM 1020.1    MM  12.8    MM   MM   MM    MM
+2023 07 24 19 30 310  6.0  8.0    MM    MM    MM  MM 1020.1    MM  12.7    MM   MM   MM    MM
+2023 07 24 19 20 310  7.0  9.0   1.5    MM   5.1 302 1019.9    MM  12.7    MM   MM   MM    MM
+  */
+
+    // Since thie uses a 3rd party CORS proxy, do not execute/parse JSON.  The data isn't even JSON, but still worth a warning.
+    var lines = this.xmlhttp.responseText.split('\n');
     var windDir = [];
     var windSpeed = [];
     var windGust = [];
     var minMoment = moment().subtract(3, 'hours');
-    for (var i=0; i<response.data.length; i++) {
-      var observation = response.data[i];
-      var observationMoment = moment.parseZone(observation.date_time).add(this.tzOffset, 'hours');
+    for (var i=0; i<lines.length; i++) {
+      var cols = lines[i].split(' ')
+      if (cols[0].startsWith('#')) continue;
+
+      var year = parseInt(cols[0]);
+      var month = parseInt(cols[1]);
+      var day = parseInt(cols[2]);
+      var hour = parseInt(cols[3]);
+      var minute = parseInt(cols[4]);
+      var wind_direction = parseInt(cols[5]);
+      var wind_speed_meters_per_second = parseInt(cols[6]);
+      var wind_gust_meters_per_second = parseInt(cols[7]);
+
+      // Month is 0-indexed
+      var observationMoment = moment.utc([year, month-1, day, hour, minute]);
 
       // Filter out data that is not within the last three hours
       if (!observationMoment.isAfter(minMoment)) continue;
 
-      windDir.push({x: observationMoment, y: observation['wind_from_direction (degree)']});
-      windSpeed.push({x: observationMoment, y: Math.round(observation['wind_speed (m/s)'] * 2.23694)});
-      windGust.push({x: observationMoment, y: Math.round(observation['wind_speed_of_gust (m/s)'] * 2.23694)});
+      windDir.push({x: observationMoment, y: wind_direction});
+      windSpeed.push({x: observationMoment, y: Math.round(wind_speed_meters_per_second * 2.23694)});
+      windGust.push({x: observationMoment, y: Math.round(wind_gust_meters_per_second * 2.23694)});
     }
     this.createChart(windSpeed, windGust, windDir);
   }