从文件

Question

我从天气api中提取数据，只想让你每隔十分钟从api中拉出一次，所以我想我会把json字符串保存到一个文件并保存拉到文件的时间所以我可以将当​​前时间与最后一次拉动时间进行比较，然后从文件或api中提取数据。 if语句似乎工作得很好。当diff超过600时，它会从api中提取数据并显示数据，但是当diff小于600时，数组似乎不一样......

任何见解都会非常感激！

function get_weather_data() {
    //define filepath to save/read/write weather data
    $weatherData = "";
    $weatherDataFile = "assets/docs/weather.json";

    //define filepath to save/read/write last api call time
    $prevTimeFile = "assets/docs/prevtime.txt";
    $prevTime = file_get_contents($prevTimeFile);
    $currTime = time();
    $diff = ($currTime - $prevTime);

    //If diff is longer than 10 mins (600 secs) then pull from api
    if ($diff < 600) { //get weather data from file
    $weatherData = file_get_contents($weatherDataFile);
    }
    else { //get weather data from api
    $request = ('http://api.openweathermap.org/data/2.5/forecast/city?id=4699066&APPID=xxxxxxxxxxxxxxxxxx');

    $weatherData = file_get_contents($request);

    //save api data back to weatherData file
    $wFile = fopen($weatherDataFile, "cb");
    fwrite($wFile, $weatherData);
    fclose($wFile);

    //save current time of data to prevTimeFile
    $tFile = fopen($prevTimeFile, "cb");
    fwrite($tFile, time() );
    fclose($tFile);
    }
    $weather = json_decode($weatherData, true);

    echo $diff;
    echo $weather['city']['name'];
}