weathers: rain, sleep and shines.

public_html/weather.php

@@ -0,0 +1,91 @@
+<?php
+
+const CACHE_PATH = '/weather';
+
+function response_code($code, $why)
+{
+    header("HTTP/1.1 $code $why");
+    exit(0);
+}
+
+function weather_cache_path($lat, $lon)
+{
+    $t = time();
+    $d = date('Y-m-d h', $t);
+    $m = date('i', $t);
+
+    // One per coord per 15 mins
+    $file = md5(sprintf("%s Q%d:%.4f:%.4f", $d, $m/15, $lat, $lon));
+
+    $path = $_SERVER["DOCUMENT_ROOT"] .'/'. CACHE_PATH . '/'. $file;
+    return $path;
+}
+
+function weather_cache_get($lat, $lon)
+{
+    $path = weather_cache_path($lat, $lon);
+    if (file_exists($path)) {
+        $json = file_get_contents($path);
+        if ($json === false) {
+            response_code(500, "Internal Server Error");
+        }
+        return file_get_contents($path);
+    }
+    return null;
+}
+
+function weather_cache_save($lat, $lon, $json)
+{
+    $path = weather_cache_path($lat, $lon);
+    if (file_put_contents($path, $json) === false) {
+        response_code(500, "Internal Server Error");
+    }
+}
+
+function weather_get($lat, $lon)
+{
+    $json = weather_cache_get($lat, $lon);
+    if (isset($json)) return $json;
+
+    $url = "https://api.met.no/weatherapi/locationforecast/2.0/compact?lat=$lat&lon=$lon";
+    $c = curl_init();
+    curl_setopt($c, CURLOPT_USERAGENT, "eWeatherProxy/1.0");
+    curl_setopt($c, CURLOPT_URL, $url);
+    curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
+
+    $json = curl_exec($c);
+    $s = curl_getinfo($c, CURLINFO_RESPONSE_CODE);
+    curl_close($c);
+    if ($s != 200) {
+        response_code($s, "Meh Meh Meh");
+    }
+
+    weather_cache_save($lat, $lon, $json);
+
+    return $json;
+}
+
+function main()
+{
+    if ($_SERVER['REQUEST_METHOD'] !== "GET") {
+        response_code(405, "Method Not Allowed");
+    }
+
+    if ((count($_GET) != 2) || (!isset($_GET['lon'])) || (!isset($_GET['lat']))) {
+        response_code(400, "Bad Request");
+    }
+
+    $lat = floatval($_GET['lat']);
+    $lon = floatval($_GET['lon']);
+    if ((($lat < -90) || ($lat > 90)) || (($lon < -180) || ($lon > 180))) {
+        response_code(400, "Bad Request");
+    }
+
+    $resp = weather_get($lat, $lon);
+    header('Content-Length: ' . strlen($resp));
+    header('Content-Type: application/json; charset=utf-8');
+    print $resp;
+}
+
+MAIN();
+?>