Experiences with Go

For a few months now, I’ve been programming mostly in Go. Go is a programming language developed by Google, some kind of modern version of C.

Instead of listing here all the findings, I’ll just point to the excellent summary by Sylvain Vallez. With my couple of months of experience in Go, I can fully agree with Sylvain’s points.

When I think of Go, the first thing that comes to my mind is the error handling. Probably half of my code is for error handling:

if err != nil {
   return err
}

But overall I’m quite satisfied with Go. It gets the job done, and I like statically typed languages. If it had generics, I might even enjoy using it.

Laravel Notification Channel for Zoner SMS-Gateway

We decided to use Zoner SMS-Gateway for sending SMS messages in a Laravel application I developed for a client. It is a Finnish service for sending SMS messages with a simple HTTP API.

In Laravel, Notification is the abstraction for any kind of message that can be sent via a Notification Channel. Laravel includes implementations for some notification channels, and there are community-provided ones in Laravel Notification Channels site.

There was no notification channel implementation for Zoner, so I created one. As instructed in Laravel Notification Channels site, I made a pull request to get my implementation listed there, but so far there hasn’t been any reaction to it. I wonder if there is anyone updating the site any more. Meanwhile, you can get the implementation from our own GitHub repository.

WordCamp Jyväskylä

Today I attended WordCamp Jyväskylä, a one-day event focused on WordPress, mostly from developer’s point of view this time. The event had presentations on two tracks, and it was difficult to choose which track to attend as both tracks had interesting presentations.  I chose these presentations / workshops:

Timeout at getCurrentPosition in Cordova app on Android

I made a simple Cordova application that wraps the web site of a client. The app asked for the current location using the “official” Geolocation plugin (cordova-plugin-geolocation), but it turned out quite unstable on Android. Sometimes it just stopped providing location. Someone suggested rebooting the phone as a fix, which did help, but is not a very good solution in the long term.

Somewhere I saw that Google suggests using its Play Services API for getting the location, instead of the vanilla Android API. Then I found Google Location Services for Cordova plugin that uses the Play Services location API. Somebody in Stack Overflow suggested that too. The original geolocation plugin gets its location from the webview, which I suppose gets it from the vanilla Android API.

Because the Google Location Services plugin is naturally for Android only, I still use the geolocation plugin on iOS. Here’s the code that uses the Google Location Services plugin if it exists and the default one otherwise:

var locationService = navigator.geolocation;
if (cordova && 'plugins' in cordova && 'locationServices' in cordova.plugins) {
  locationService = cordova.plugins.locationServices.geolocation;
  console.log('Using cordova-plugin-locationservices');
}

locationService.getCurrentPosition(
  function (position) {
    var positionStr = position.coords.latitude + ',' + position.coords.longitude;
    console.log('Got position: ' + positionStr);
    // ...
  },
  function (err) {
    console.log('Did not got position: code=' + err.code + ' message=' + err.message);
    // ...
  },
  {
    enableHighAccuracy: false,
    maximumAge: 30*60*1000, // 30 min
    timeout: 20000 // ms
   }
);

Issue with WordPress text widget, Black Studio TinyMCE Widget and icl_sw_filters_widget_text

We had a problem where the text of plain old WordPress text widgets was not showing on pages. Error log showed entries like

[13-Dec-2017 09:25:29 UTC] PHP Warning: call_user_func_array() expects parameter 1 to be a valid callback, function 'icl_sw_filters_widget_text' not found or invalid function name in /home/itukylat/public_html/wp-includes/class-wp-hook.php on line 288

Function icl_sw_filters_widget_text is defined in WPML String Translation plugin, but we didn’t have that installed. The only place where I could find hook to icl_sw_filters_widget_text being added is in Black Studio Tiny MCE Widget plugin, in black-studio-tinymce-widget/includes/class-compatibility-plugins.php, function wpml_widget_after:

if ( false === has_filter( 'widget_text', 'icl_sw_filters_widget_text' ) && function_exists( 'icl_sw_filters_widget_text' ) || version_compare( $this->wpml_get_version(), '3.8.0' ) >= 0 ) {
    add_filter( 'widget_text', 'icl_sw_filters_widget_text', 0 );
}

and indeed that gets called, even though there is no icl_sw_filters_widget_text function anywhere.

I suspect there is something wrong with the if statement, but I didn’t dig any deeper. But I did report the issue to Black Studio Tiny MCE Widget author.

Meanwhile, as a workaround I defined my own icl_sw_filters_widget_text function:

function icl_sw_filters_widget_text($text) {
    return $text;
}

Now the texts in text widgets show up again.