update draft

content/posts/display-tempest-weather-static-site/index.md

@@ -3,20 +3,24 @@ title: "Displaying Data from Tempest Weather Station on a Static Site"
 date: 2024-02-10
 # lastmod: 2024-02-10
 draft: true
-description: "Using a GitHub Actions workflow as a sort of API proxy to retrieve data from an authenticated "
+description: "Using a GitHub Actions workflow to retrieve data from an authenticated API, posting results to a publicly-accessible pastebin, and displaying them on a static web site."
 featured: false
 toc: true
 comments: true
-categories: Tips # Backstage, ChromeOS, Code, Self-Hosting, VMware
+categories: Backstage
 tags:
   - api
   - javascript
   - meta
   - serverless
 ---
-As I covered briefly [in a recent Scribble](https://scribbles.jbowdre.lol/post/near-realtime-weather-on-profile-lol-ku4yq-zr), I spent some time this week with integrating data from my [Weatherflow Tempest weather station](https://shop.weatherflow.com/products/tempest) into my [omg.lol homepage](https://jbowdre.lol). That page is rendered as a static site, so I needed a way to do this *without* including secrets like the station ID or API token in the client-side JavaScript.
+As I covered briefly [in a recent Scribble](https://scribbles.jbowdre.lol/post/near-realtime-weather-on-profile-lol-ku4yq-zr), I was inspired by the way [Kris's omg.lol page](https://kris.omg.lol/) displays realtime data from his [Weatherflow Tempest weather station](https://shop.weatherflow.com/products/tempest). I thought that was really neat and wanted to do the same on [my omg.lol page](https://jbowdre.lol) with data from my own Tempest, but I wanted to do it without including my station ID or API token directly in the client-side JavaScript.
 
-I realized I could use a GitHub Actions workflow to retrieve the data from the authenticated Tempest API, post it somewhere publicly accessible, and then have the client-side code fetch the data from there without needing any authentication. This post will cover how I did it.
+I realized I could use a GitHub Actions workflow to retrieve the data from the authenticated Tempest API, post it somewhere publicly accessible, and then have the client-side code fetch the data from there without needing any authentication. After a few days of tinkering, I came up with a presentation I'm happy with.
+
+![Glowing green text on a dark grey background showing weather data like conditions, temperature, and pressure, with a note that the data is 2 minutes old](finished-product.png)
+
+This post will cover how I did it.
 
 ### Retrieve Weather Data from Tempest API
 To start, I want to play with the API a bit to see what the responses look like. Before I can talk to the API, though, I need to generate a new token for my account at `https://tempestwx.com/settings/tokens`. I also make a note of my station ID, and store both of those values in my shell for easier use.
@@ -276,10 +280,12 @@ defaults:
 ```
 
 The `on` block defines when the workflow will run:
-1. On a `cron` schedule which fires (roughly) every five minutes
+1. On a schedule which fires (roughly[^cron]) every five minutes
 2. On a `workflow_dispatch` event (so I can start it manually if I want)
 3. When changes are pushed to the `main` branch
 
+[^cron]: Per [the docs](https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#schedule), runs can run *at most* once every five minutes, and they may be delayed (or even canceled) if a runner isn't available due to heavy load.
+
 And the `defaults` block makes sure that the following scripts will be run in `bash`:
 
 ```yaml
@@ -317,4 +323,575 @@ jobs:
 
 Each step in the `jobs` section should look pretty familiar since those are almost exactly the commands that I used earlier. The only real difference is that they now use the format `${{ secrets.SECRET_NAME }}` to pull in the repository secrets I just created.
 
-Once I save, commit, and push this new file to the repo, it will automatically execute, and I can go to the [Actions](https://github.com/jbowdre/lolz/actions) tab to confirm that the run was succesful. I can also check `https://paste.jbowdre.lol/tempest.json` to confirm that the contents have updated.
+Once I save, commit, and push this new file to the repo, it will automatically execute, and I can go to the [Actions](https://github.com/jbowdre/lolz/actions) tab to confirm that the run was succesful. I can also check `https://paste.jbowdre.lol/tempest.json` to confirm that the contents have updated.
+
+### Show Weather on Homepage
+By this point, I've fetched the weather data from Tempest, filtered it for just the fields I want to see, and posted the condensed JSON to a publicly-accessible pastebin. Now I just need to figure out how to make it show up on my omg.lol homepage. Rather than implementing these changes on the public site right away, I'll start with a barebones `tempest.html` that I can test with locally. Here's the initial structure that I'll be building from:
+
+```html
+<!-- torchlight! {"lineNumbers": true} -->
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8">
+    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.1.2/css/all.min.css" integrity="sha512-1sCRPdkRXhBV2PBLUdRb4tMg1w2YPf37qatUFeS7zlBy7jJI8Lf4VHwWfZZfpXtYSLy85pkm9GaYVYMfw5BC1A==" crossorigin="anonymous">
+    <title>Weather Test</title>
+    <script>
+      // TODO
+    </script>
+  </head>
+  <body>
+    <h1>Local Weather</h1>
+    <ul>
+      <li>Conditions: <i class='fa-solid fa-cloud-sun-rain'></i><span id="conditions"></span></li>
+      <li>Temperature: <i class='fa-solid fa-temperature-half'></i> <span id="temp"></span></li>
+      <li>Humidity: <span id="humidity"></span></li>
+      <li>Wind: <span id="wind"></span></li>
+      <li>Precipitation: <i class='fa-solid fa-droplet-slash'></i><span id="rainToday"></span></li>
+      <li>Pressure: <i class='fa-solid fa-arrow-right-long'></i><span id="pressure"></span></li>
+      <li><i>Last Update: <span id="time"></span></i></li>
+  </body>
+</html>
+```
+
+In the `<head>`, I'm specifying the character set so that I won't get any weird reactions when using exotic symbols like `°`, and I'm also pulling in the [Font Awesome](https://fontawesome.com) stylesheet so I can easily use those icons in the weather display. The `<body>` just holds empty `<span>`s that will later be populated with data via JavaScript.
+
+I only included a few icons here. I'm going to try to make those icons dynamic so that they'll change depending on how hot/cold it is or what the pressure trend is doing. I don't plan to toy with the humidity, wind, or last update icons (yet) so I'm not going to bother with testing those locally.
+
+With that framework in place, I can use `python3 -m http.server 8080` to serve the page at `http://localhost:8080/tempest.html`.
+
+![Simple local web page showing placeholders for weather information](local-test-blank.png)
+
+It's rather sparse, but it works. I won't be tinkering with any of that HTML from this point on, I'll just focus on the (currently-empty) `<script>` block. I don't think I'm super great with JavaScript, so I leaned heavily upon the code on [Kris's page](https://kris.omg.lol) to get started and then put my own spin on it as I went along.
+
+Before I can do much of anything, though, I'll need to start by retrieving the JSON data from my paste.lol endpoint and parsing the data:
+
+```javascript
+// torchlight! {"lineNumbers": true}
+const wx_endpoint = 'https://paste.jbowdre.lol/tempest.json/raw'; // [tl! reindex(8)]
+// fetch data from pastebin
+fetch(wx_endpoint)
+  .then(res => res.json())
+  .then(function(res){
+    // parse data
+    let updateTime = res.time;
+    let conditions = res.conditions;
+    let temp = res.temperature;
+    let humidity = res.humidity;
+    let wind = res.wind_gust;
+    let rainToday = res.rain_today;
+    let pressure = res.pressure;
+
+    // display data
+    document.getElementById('time').innerHTML = updateTime;
+    document.getElementById('conditions').innerHTML = conditions;
+    document.getElementById('temp').innerHTML = temp;
+    document.getElementById('humidity').innerHTML = humidity;
+    document.getElementById('wind').innerHTML = wind;
+    document.getElementById('rainToday').innerHTML = rainToday;
+    document.getElementById('pressure').innerHTML = pressure;
+  });
+```
+
+So this is fetching the data from the pastebin, mapping variables to the JSON fields, and using `document.getElementById()` to select the placeholder `<span>`s by their id and replace the corresponding `innerHTML` with the appropriate values.
+
+The result isn't very pretty, but it's a start:
+
+![Simple local web page showing basic weather information without any units, and the timestamp is in Unix format showing the number of seconds since January 1, 1970](local-test-raw.png)
+
+That [Unix epoch timestamp](https://en.wikipedia.org/wiki/Unix_time) stands out as being particularly unwieldy. Instead of the exact timestamp, I'd prefer to show that as the relative time since the last update. I'll do that with the [`Intl.RelativeTimeFormat` object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/RelativeTimeFormat).
+
+```javascript
+// torchlight! {"lineNumbers": true}
+const wx_endpoint = 'https://paste.jbowdre.lol/tempest.json/raw'; // [tl! reindex(8)]
+// get ready to calculate relative time [tl! ++:start **:start]
+const units = {
+  year  : 24 * 60 * 60 * 1000 * 365,
+  month : 24 * 60 * 60 * 1000 * 365/12,
+  day   : 24 * 60 * 60 * 1000,
+  hour  : 60 * 60 * 1000,
+  minute: 60 * 1000,
+  second: 1000
+}
+let rtf = new Intl.RelativeTimeFormat('en', { numeric: 'auto' })
+let getRelativeTime = (d1, d2 = new Date()) => {
+  let elapsed = d1 - d2
+  for (var u in units)
+    if (Math.abs(elapsed) > units[u] || u === 'second')
+      return rtf.format(Math.round(elapsed/units[u]), u)
+} // [tl! ++:end **:end]
+// fetch data from pastebin
+fetch(wx_endpoint)
+  .then(res => res.json())
+  .then(function(res){
+    // calculate age of last update [tl! ++:start **:start]
+    let updateTime = res.time;
+    updateTime = parseInt(updateTime);
+    updateTime = updateTime*1000;
+    updateTime = new Date(updateTime);
+    let updateAge = getRelativeTime(updateTime);
+
+    // parse data
+    let updateTime = res.time; // [tl! -- reindex(-1)]
+    let conditions = res.conditions;
+    let temp = res.temperature;
+    let humidity = res.humidity;
+    let wind = res.wind_gust;
+    let rainToday = res.rain_today;
+    let pressure = res.pressure;
+
+    // display data
+    document.getElementById('time').innerHTML = updateAge; // [tl! ++ **]
+    document.getElementById('time').innerHTML = updateTime; // [tl! -- reindex(-1)]
+    document.getElementById('conditions').innerHTML = conditions;
+    document.getElementById('temp').innerHTML = temp;
+    document.getElementById('humidity').innerHTML = humidity;
+    document.getElementById('wind').innerHTML = wind;
+    document.getElementById('rainToday').innerHTML = rainToday;
+    document.getElementById('pressure').innerHTML = pressure;
+  });
+```
+
+That's a bit more friendly:
+
+![The same simple weather display but the last update is now "2 minutes ago"](local-test-reltime.png)
+
+Alright, let's massage some of the other fields a little. I'll add units and labels, translate temperature and speed values to metric for my international friends, and combine a few additional fields for more context. I'm also going to make sure everything is lowercase to match the, uh, *aesthetic* of my omg page.
+
+```javascript
+// torchlight! {"lineNumbers": true}
+const wx_endpoint = 'https://paste.jbowdre.lol/tempest.json/raw'; // [tl! reindex(8) collapse:start]
+// get ready to calculate relative time
+const units = {
+  year  : 24 * 60 * 60 * 1000 * 365,
+  month : 24 * 60 * 60 * 1000 * 365/12,
+  day   : 24 * 60 * 60 * 1000,
+  hour  : 60 * 60 * 1000,
+  minute: 60 * 1000,
+  second: 1000
+}
+let rtf = new Intl.RelativeTimeFormat('en', { numeric: 'auto' })
+let getRelativeTime = (d1, d2 = new Date()) => {
+  let elapsed = d1 - d2
+  for (var u in units)
+    if (Math.abs(elapsed) > units[u] || u === 'second')
+      return rtf.format(Math.round(elapsed/units[u]), u)
+}
+// fetch data from pastebin
+fetch(wx_endpoint)
+  .then(res => res.json())
+  .then(function(res){
+    // calculate age of last update
+    let updateTime = res.time;
+    updateTime = parseInt(updateTime);
+    updateTime = updateTime*1000;
+    updateTime = new Date(updateTime);
+    let updateAge = getRelativeTime(updateTime); // [tl! collapse:end]
+
+    // parse data
+    let updateTime = res.time;
+    let conditions = (res.conditions).toLowerCase(); // [tl! ++ **]
+    let conditions = res.conditions; // [tl! -- reindex(-1)]
+    let temp = `${res.temperature}°f (${(((res.temperature - 32) * 5) / 9).toFixed(1)}°c)`; // [tl! ++ **]
+    let temp = res.temperature; // [tl! -- reindex(-1)]
+    let humidity = `${res.humidity}% humidity`; // [tl! ++ **]
+    let humidity = res.humidity; // [tl! -- reindex(-1)]
+    let wind = `${res.wind_gust}mph (${(res.wind_gust*1.609344).toFixed(1)}kph) from ${(res.wind_direction).toLowerCase()}`; // [tl! ++ **]
+    let wind = res.wind_gust; // [tl! -- reindex(-1)]
+    let rainToday = `${res.rain_today}" rain today`; // [tl! ++ **]
+    let rainToday = res.rain_today; // [tl! -- reindex(-1)]
+    let pressureTrend = res.pressure_trend; // [tl! ++:1 **:1]
+    let pressure = `${res.pressure}inhg and ${pressureTrend}`;
+    let pressure = res.pressure; // [tl! -- reindex(-1)]
+
+    // display data [tl! collapse:start]
+    document.getElementById('time').innerHTML = updateAge;
+    document.getElementById('time').innerHTML = updateTime;
+    document.getElementById('conditions').innerHTML = conditions;
+    document.getElementById('temp').innerHTML = temp;
+    document.getElementById('humidity').innerHTML = humidity;
+    document.getElementById('wind').innerHTML = wind;
+    document.getElementById('rainToday').innerHTML = rainToday;
+    document.getElementById('pressure').innerHTML = pressure;
+  }); // [tl! collapse:end]
+```
+
+That's a bit better:
+
+![The sample webpage showing formatted strings for each weather item](local-test-strings.png)
+
+Now let's add some conditionals into the mix. I'd like to display the `feels_like` temperature but only if it's five or more degrees away from the actual air temperature. And if there hasn't been any rain, the page should show `no rain today` instead of `0.00" rain today`.
+
+```javascript
+// torchlight! {"lineNumbers": true}
+const wx_endpoint = 'https://paste.jbowdre.lol/tempest.json/raw'; // [tl! reindex(8) collapse:start]
+// get ready to calculate relative time
+const units = {
+  year  : 24 * 60 * 60 * 1000 * 365,
+  month : 24 * 60 * 60 * 1000 * 365/12,
+  day   : 24 * 60 * 60 * 1000,
+  hour  : 60 * 60 * 1000,
+  minute: 60 * 1000,
+  second: 1000
+}
+let rtf = new Intl.RelativeTimeFormat('en', { numeric: 'auto' })
+let getRelativeTime = (d1, d2 = new Date()) => {
+  let elapsed = d1 - d2
+  for (var u in units)
+    if (Math.abs(elapsed) > units[u] || u === 'second')
+      return rtf.format(Math.round(elapsed/units[u]), u)
+} //
+// fetch data from pastebin
+fetch(wx_endpoint)
+  .then(res => res.json())
+  .then(function(res){
+    // calculate age of last update
+    let updateTime = res.time;
+    updateTime = parseInt(updateTime);
+    updateTime = updateTime*1000;
+    updateTime = new Date(updateTime);
+    let updateAge = getRelativeTime(updateTime); // [tl! collapse:end]
+
+    // parse data
+    let updateTime = res.time;
+    let conditions = (res.conditions).toLowerCase();
+    let tempDiff = Math.abs(res.temperature - res.feels_like); // [tl! ++ **]
+    let temp = `${res.temperature}°f (${(((res.temperature - 32) * 5) / 9).toFixed(1)}°c)`;
+    if (tempDiff >= 5) { // [tl! ++:2 **:2]
+      temp += `, feels ${res.feels_like}°f (${(((res.feels_like - 32) *5) / 9).toFixed(1)}°c)`;
+    }
+    let humidity = `${res.humidity}% humidity`;
+    let wind = `${res.wind_gust}mph (${(res.wind_gust*1.609344).toFixed(1)}kph) from ${(res.wind_direction).toLowerCase()}`;
+    let rainToday; // [tl! ++:5 **:5]
+    if (res.rain_today === 0) {
+      rainToday = 'no rain today';
+    } else {
+      rainToday = `${res.rain_today}" rain today`;
+    }
+    let rainToday = `${res.rain_today}" rain today`; // [tl! -- reindex(-1)]
+    let pressureTrend = res.pressure_trend;
+    let pressure = `${res.pressure}inhg and ${pressureTrend}`;
+
+    // display data [tl! collapse:start]
+    document.getElementById('time').innerHTML = updateAge;
+    document.getElementById('time').innerHTML = updateTime;
+    document.getElementById('conditions').innerHTML = conditions;
+    document.getElementById('temp').innerHTML = temp;
+    document.getElementById('humidity').innerHTML = humidity;
+    document.getElementById('wind').innerHTML = wind;
+    document.getElementById('rainToday').innerHTML = rainToday;
+    document.getElementById('pressure').innerHTML = pressure;
+  }); // [tl! collapse:end]
+```
+
+For testing this, I can manually alter[^alter] the contents of the pastebin to ensure the values are what I need:
+
+[^alter]: My dishonest values will just get corrected the next time the workflow is triggered.
+
+```json
+// torchlight! {"lineNumbers": true}
+{
+  "temperature": 57, // [tl! **]
+  "conditions": "Rain Likely",
+  "feels_like": 67, // [tl! **]
+  "icon": "rainy",
+  "rain_today": 0, // [tl! **]
+  "pressure_trend": "steady",
+  "humidity": 92,
+  "pressure": 29.91,
+  "time": 1707676590,
+  "wind_direction": "WSW",
+  "wind_gust": 2
+}
+```
+
+![Local test page reflecting "57°f (13.9°c), feels 67°f (19.4°c)" and "no rain today"](local-test-conditional.png)
+
+The final touch will be to change the icons depending on the values of certain fields:
+- The conditions icon will vary from <i class="fa-solid fa-sun"></i> to <i class="fa-solid fa-cloud-bolt"></i>, roughly corresponding to the `icon` value from the Tempest API.
+- The temperature icon will range from <i class="fa-solid fa-thermometer-empty"></i> to <i class="fa-solid fa-thermometer-full"></i> depending on the temperature.
+- The precipitation icon will be <i class="fa-solid fa-droplet-slash"></i> for no precipitation, and progress through <i class="fa-solid fa-glass-water-droplet"></i> and <i class="fa-solid fa-glass-water"></i> for a bit more rain, and cap out at <i class="fa-solid fa-bucket"></i> for lots of rain[^rain].
+- The pressure icon should change based on the trend: <i class="fa-solid fa-arrow-trend-up"></i>, <i class="fa-solid fa-arrow-right-long"></i>, and <i class="fa-solid fa-arrow-trend-down"></i>.
+
+[^rain]: Okay, admittedly this progression isn't perfect, but it's the best I could come up with within the free FA icon set.
+
+I'll set up a couple of constants to define the ranges, and a few more for mapping the values to icons. Then I'll use the `Array.prototype.find` method to select the appropriate `upper` value from each range. And then I leverage `document.getElementsByClassName` to match the placeholder icon classes and dynamically replace them.
+
+```javascript
+// torchlight! {"lineNumbers": true}
+const wx_endpoint = 'https://paste.jbowdre.lol/tempest.json/raw'; // [tl! reindex(8) collapse:start]
+// get ready to calculate relative time
+const units = {
+  year  : 24 * 60 * 60 * 1000 * 365,
+  month : 24 * 60 * 60 * 1000 * 365/12,
+  day   : 24 * 60 * 60 * 1000,
+  hour  : 60 * 60 * 1000,
+  minute: 60 * 1000,
+  second: 1000
+}
+let rtf = new Intl.RelativeTimeFormat('en', { numeric: 'auto' })
+let getRelativeTime = (d1, d2 = new Date()) => {
+  let elapsed = d1 - d2
+  for (var u in units)
+    if (Math.abs(elapsed) > units[u] || u === 'second')
+      return rtf.format(Math.round(elapsed/units[u]), u)
+} // [tl! collapse:end]
+
+// set up temperature and rain ranges [tl! ++:start **:start]
+const tempRanges = [
+  { upper: 32, label: 'cold' },
+  { upper: 60, label: 'cool' },
+  { upper: 80, label: 'warm' },
+  { upper: Infinity, label: 'hot' }
+];
+const rainRanges = [
+  { upper: 0.02, label: 'none' },
+  { upper: 0.2, label: 'light' },
+  { upper: 1.4, label: 'moderate' },
+  { upper: Infinity, label: 'heavy' }
+]
+
+// maps for selecting icons
+const CLASS_MAP_PRESS = {
+  'steady': 'fa-solid fa-arrow-right-long',
+  'rising': 'fa-solid fa-arrow-trend-up',
+  'falling': 'fa-solid fa-arrow-trend-down'
+}
+const CLASS_MAP_RAIN = {
+  'none': 'fa-solid fa-droplet-slash',
+  'light': 'fa-solid fa-glass-water-droplet',
+  'moderate': 'fa-solid fa-glass-water',
+  'heavy': 'fa-solid fa-bucket'
+}
+const CLASS_MAP_TEMP = {
+  'hot': 'fa-solid fa-thermometer-full',
+  'warm': 'fa-solid fa-thermometer-half',
+  'cool': 'fa-solid fa-thermometer-quarter',
+  'cold': 'fa-solid fa-thermometer-empty'
+}
+const CLASS_MAP_WX = {
+  'clear-day': 'fa-solid fa-sun',
+  'clear-night': 'fa-solid fa-moon',
+  'cloudy': 'fa-solid fa-cloud',
+  'foggy': 'fa-solid fa-cloud-showers-smog',
+  'partly-cloudy-day': 'fa-solid fa-clouds-sun',
+  'partly-cloudy-night': 'fa-solid fa-clouds-moon',
+  'possibly-rainy-day': 'fa-solid fa-cloud-sun-rain',
+  'possibly-rainy-night': 'fa-solid fa-cloud-moon-rain',
+  'possibly-sleet-day': 'fa-solid fa-cloud-meatball',
+  'possibly-sleet-night': 'fa-solid fa-cloud-moon-rain',
+  'possibly-snow-day': 'fa-solid fa-snowflake',
+  'possibly-snow-night': 'fa-solid fa-snowflake',
+  'possibly-thunderstorm-day': 'fa-solid fa-cloud-bolt',
+  'possibly-thunderstorm-night': 'fa-solid fa-cloud-bolt',
+  'rainy': 'fa-solid fa-cloud-showers-heavy',
+  'sleet': 'fa-solid fa-cloud-rain',
+  'snow': 'fa-solid fa-snowflake',
+  'thunderstorm': 'fa-solid fa-cloud-bolt',
+  'windy': 'fa-solid fa-wind',
+} // [tl! ++:end **:end]
+
+// fetch data from pastebin [tl! collapse:10]
+fetch(wx_endpoint)
+  .then(res => res.json())
+  .then(function(res){
+    // calculate age of last update
+    let updateTime = res.time;
+    updateTime = parseInt(updateTime);
+    updateTime = updateTime*1000;
+    updateTime = new Date(updateTime);
+    let updateAge = getRelativeTime(updateTime);
+
+    // parse data
+    let updateTime = res.time;
+    let conditions = (res.conditions).toLowerCase();
+    let tempDiff = Math.abs(res.temperature - res.feels_like);
+    let temp = `${res.temperature}°f (${(((res.temperature - 32) * 5) / 9).toFixed(1)}°c)`;
+    if (tempDiff >= 5) {
+      temp += `, feels ${res.feels_like}°f (${(((res.feels_like - 32) *5) / 9).toFixed(1)}°c)`;
+    }
+    let tempLabel = (tempRanges.find(range => res.feels_like < range.upper)).label; // [tl! ++ **]
+    let humidity = `${res.humidity}% humidity`;
+    let wind = `${res.wind_gust}mph (${(res.wind_gust*1.609344).toFixed(1)}kph) from ${(res.wind_direction).toLowerCase()}`;
+    let rainLabel = (rainRanges.find(range => res.rain_today < range.upper)).label; // [tl! ++ **]
+    let rainToday;
+    if (res.rain_today === 0) {
+      rainToday = 'no rain today';
+    } else {
+      rainToday = `${res.rain_today}" rain today`;
+    }
+    let rainToday = `${res.rain_today}" rain today`;
+    let pressureTrend = res.pressure_trend;
+    let pressure = `${res.pressure}inhg and ${pressureTrend}`;
+    let icon = res.icon; // [tl! ++ **]
+
+    // display data [tl! collapse:8]
+    document.getElementById('time').innerHTML = updateAge;
+    document.getElementById('time').innerHTML = updateTime;
+    document.getElementById('conditions').innerHTML = conditions;
+    document.getElementById('temp').innerHTML = temp;
+    document.getElementById('humidity').innerHTML = humidity;
+    document.getElementById('wind').innerHTML = wind;
+    document.getElementById('rainToday').innerHTML = rainToday;
+    document.getElementById('pressure').innerHTML = pressure;
+    // update icons [tl! ++:4 **:4]
+    document.getElementsByClassName('fa-cloud-sun-rain')[0].classList = CLASS_MAP_WX[icon];
+    document.getElementsByClassName('fa-temperature-half')[0].classList = CLASS_MAP_TEMP[tempLabel];
+    document.getElementsByClassName('fa-droplet-slash')[0].classList = CLASS_MAP_RAIN[rainLabel];
+    document.getElementsByClassName('fa-arrow-right-long')[0].classList = CLASS_MAP_PRESS[pressureTrend];
+  });
+```
+
+And I can see that the icons do indeed match the conditions:
+
+![Local test page with matching icons](local-test-dynamic-icons.png)
+
+### OMG, LOL, Let's Do It
+Now that all that prep work is out of the way, transposing the code into the live omg.lol homepage doesn't really take much effort.
+
+I'll just use the online editor to drop this at the bottom of my web page:
+
+```markdown
+// torchlight! {"lineNumbers":true}
+# /proc/wx <!-- [tl! reindex(47)] -->
+- <span id="conditions"></span> {cloud-sun-rain}
+- <span id="temp"></span> {temperature-half}
+- <span id="humidity"></span> {droplet}
+- <span id="wind"></span> {wind}
+- <span id="rainToday"></span> {droplet-slash}
+- <span id="pressure"></span> {arrow-right-long}
+- <i>as of <span id="time"></span></i> {clock}
+```
+
+A bit further down the editor page, there's a box for inserting additional content into the page's `<head>` block. That's a great place to past in the entirety of my script:
+
+```html
+// torchlight! {"lineNumbers":true}
+<script> // [tl! reindex(3)]
+  const wx_endpoint = 'https://paste.jbowdre.lol/tempest.json/raw';
+  // get ready to calculate relative time
+  const units = {
+    year  : 24 * 60 * 60 * 1000 * 365,
+    month : 24 * 60 * 60 * 1000 * 365/12,
+    day   : 24 * 60 * 60 * 1000,
+    hour  : 60 * 60 * 1000,
+    minute: 60 * 1000,
+    second: 1000
+  }
+  let rtf = new Intl.RelativeTimeFormat('en', { numeric: 'auto' })
+  let getRelativeTime = (d1, d2 = new Date()) => {
+    let elapsed = d1 - d2
+    for (var u in units)
+      if (Math.abs(elapsed) > units[u] || u === 'second')
+        return rtf.format(Math.round(elapsed/units[u]), u)
+  }
+
+  // set up temperature and rain ranges
+  const tempRanges = [
+    { upper: 32, label: 'cold' },
+    { upper: 60, label: 'cool' },
+    { upper: 80, label: 'warm' },
+    { upper: Infinity, label: 'hot' }
+  ];
+  const rainRanges = [
+    { upper: 0.02, label: 'none' },
+    { upper: 0.2, label: 'light' },
+    { upper: 1.4, label: 'moderate' },
+    { upper: Infinity, label: 'heavy' }
+  ]
+
+  // maps for selecting icons
+  const CLASS_MAP_PRESS = {
+    'steady': 'fa-solid fa-arrow-right-long',
+    'rising': 'fa-solid fa-arrow-trend-up',
+    'falling': 'fa-solid fa-arrow-trend-down'
+  }
+  const CLASS_MAP_RAIN = {
+    'none': 'fa-solid fa-droplet-slash',
+    'light': 'fa-solid fa-glass-water-droplet',
+    'moderate': 'fa-solid fa-glass-water',
+    'heavy': 'fa-solid fa-bucket'
+  }
+  const CLASS_MAP_TEMP = {
+    'hot': 'fa-solid fa-thermometer-full',
+    'warm': 'fa-solid fa-thermometer-half',
+    'cool': 'fa-solid fa-thermometer-quarter',
+    'cold': 'fa-solid fa-thermometer-empty'
+  }
+  const CLASS_MAP_WX = {
+    'clear-day': 'fa-solid fa-sun',
+    'clear-night': 'fa-solid fa-moon',
+    'cloudy': 'fa-solid fa-cloud',
+    'foggy': 'fa-solid fa-cloud-showers-smog',
+    'partly-cloudy-day': 'fa-solid fa-clouds-sun',
+    'partly-cloudy-night': 'fa-solid fa-clouds-moon',
+    'possibly-rainy-day': 'fa-solid fa-cloud-sun-rain',
+    'possibly-rainy-night': 'fa-solid fa-cloud-moon-rain',
+    'possibly-sleet-day': 'fa-solid fa-cloud-meatball',
+    'possibly-sleet-night': 'fa-solid fa-cloud-moon-rain',
+    'possibly-snow-day': 'fa-solid fa-snowflake',
+    'possibly-snow-night': 'fa-solid fa-snowflake',
+    'possibly-thunderstorm-day': 'fa-solid fa-cloud-bolt',
+    'possibly-thunderstorm-night': 'fa-solid fa-cloud-bolt',
+    'rainy': 'fa-solid fa-cloud-showers-heavy',
+    'sleet': 'fa-solid fa-cloud-rain',
+    'snow': 'fa-solid fa-snowflake',
+    'thunderstorm': 'fa-solid fa-cloud-bolt',
+    'windy': 'fa-solid fa-wind',
+  }
+
+  // fetch data from pastebin
+  fetch(wx_endpoint)
+    .then(res => res.json())
+    .then(function(res){
+
+      // calculate age of last update
+      let updateTime = res.time;
+      updateTime = parseInt(updateTime);
+      updateTime = updateTime*1000;
+      updateTime = new Date(updateTime);
+      let updateAge = getRelativeTime(updateTime);
+
+      // parse data
+      let conditions = (res.conditions).toLowerCase();
+      let tempDiff = Math.abs(res.temperature - res.feels_like);
+      let temp = `${res.temperature}°f (${(((res.temperature - 32) * 5) / 9).toFixed(1)}°c)`;
+      if (tempDiff >= 5) {
+        temp += `, feels ${res.feels_like}°f (${(((res.feels_like - 32) *5) / 9).toFixed(1)}°c)`;
+      }
+      let tempLabel = (tempRanges.find(range => res.feels_like < range.upper)).label;
+      let humidity = `${res.humidity}% humidity`;
+      let wind = `${res.wind_gust}mph (${(res.wind_gust*1.609344).toFixed(1)}kph) from ${(res.wind_direction).toLowerCase()}`;
+      let rainLabel = (rainRanges.find(range => res.rain_today < range.upper)).label;
+      let rainToday;
+      if (res.rain_today === 0) {
+        rainToday = 'no rain today';
+      } else {
+        rainToday = `${res.rain_today}" rain today`;
+      }
+      let pressureTrend = res.pressure_trend;
+      let pressure = `${res.pressure}inhg and ${pressureTrend}`;
+      let icon = res.icon;
+
+      // display data
+      document.getElementById('time').innerHTML = updateAge;
+      document.getElementById('conditions').innerHTML = conditions;
+      document.getElementById('temp').innerHTML = temp;
+      document.getElementById('humidity').innerHTML = humidity;
+      document.getElementById('wind').innerHTML = wind;
+      document.getElementById('rainToday').innerHTML = rainToday;
+      document.getElementById('pressure').innerHTML = pressure;
+      // update icons
+      document.getElementsByClassName('fa-cloud-sun-rain')[0].classList = CLASS_MAP_WX[icon];
+      document.getElementsByClassName('fa-temperature-half')[0].classList = CLASS_MAP_TEMP[tempLabel];
+      document.getElementsByClassName('fa-droplet-slash')[0].classList = CLASS_MAP_RAIN[rainLabel];
+      document.getElementsByClassName('fa-arrow-right-long')[0].classList = CLASS_MAP_PRESS[pressureTrend];
+    });
+</script>
+```
+
+With that, I hit the happy little **Save & Publish** button in the editor, and then revel in seeing my new weather display at the bottom of my [omg.lol page](https://jbowdre.lol):
+
+![Mobile screenshot of an omg.lol homepage with a (near) realtime weather display at the bottom](its-alive.png)
+
+I'm quite pleased with how this turned out, and I had fun learning a few JavaScript tricks in the process. I stashed the code for this little project in my [lolz repo](https://github.com/jbowdre/lolz) in case you'd like to take a look. I have some ideas for other APIs I might want to integrate in a similar way in the future so stay tuned.