[Lizmap] Publish WFS services in QGIS with Lizmap

[René-Luc Dhont]

Hi,

Here is the QGIS code

```c
// Creating a SpatiaLite database can be quite slow on some file systems
   // so we create a GDAL in-memory file, and then copy it on
   // the file system.
   GDALDriverH hDrv = GDALGetDriverByName( "SQLite" );
   if ( !hDrv )
   {
     logMessageWithReason( QStringLiteral( "GDAL SQLite driver not 
available" ) );
     return false;
   }
   const QString vsimemFilename = QStringLiteral( 
"/vsimem/qgis_cache_template_%1/features.sqlite" ).arg( 
reinterpret_cast< quintptr >( this ), QT_POINTER_SIZE * 2, 16, 
QLatin1Char( '0' ) );
   mCacheTablename = CPLGetBasename( vsimemFilename.toStdString().c_str() );
   VSIUnlink( vsimemFilename.toStdString().c_str() );
   const char *apszOptions[] = { "INIT_WITH_EPSG=NO", "SPATIALITE=YES", 
nullptr };
   GDALDatasetH hDS = GDALCreate( hDrv, 
vsimemFilename.toUtf8().constData(), 0, 0, 0, GDT_Unknown, 
const_cast<char **>( apszOptions ) );
   if ( !hDS )
   {
     logMessageWithReason( QStringLiteral( "GDALCreate() failed: %1" 
).arg( CPLGetLastErrorMsg() ) );
     return false;
   }
   GDALClose( hDS );

   // Copy the temporary database back to disk
   vsi_l_offset nLength = 0;
   GByte *pabyData = VSIGetMemFileBuffer( 
vsimemFilename.toStdString().c_str(), &nLength, TRUE );
   Q_ASSERT( !QFile::exists( mCacheDbname ) );
   VSILFILE *fp = VSIFOpenL( mCacheDbname.toStdString().c_str(), "wb" );
   if ( fp )
   {
     VSIFWriteL( pabyData, 1, nLength, fp );
     VSIFCloseL( fp );
     CPLFree( pabyData );
   }
   else
   {
     CPLFree( pabyData );
     logMessageWithReason( QStringLiteral( "Cannot copy file to %1: %2" 
).arg( mCacheDbname ).arg( CPLGetLastErrorMsg() ) );
     return false;
   }
```

So the database to store WFS Features has been created in memory with 
GDAL/OGR and the path "/vsimem/qgis_cache_template_%1/features.sqlite" 
and will be write to disk in QGIS cache directory.

The mCacheDbname is defined like that:
```c
   Q_ASSERT( mCacheDbname.isEmpty() );

   static QAtomicInt sTmpCounter = 0;
   int tmpCounter = ++sTmpCounter;
   QString cacheDirectory( acquireCacheDirectory() );
   mCacheDbname = QDir( cacheDirectory ).filePath( QStringLiteral( 
"cache_%1.sqlite" ).arg( tmpCounter ) );
   Q_ASSERT( !QFile::exists( mCacheDbname ) );
```

In the log provided by Günter, we don't have enough reason. The 
CPLGetLastErrorMsg is empty.

Günter, can you provide more logs arround the message "Cannot create 
temporary SpatiaLite cache.: Cannot copy file to" ?

Regards,
René-Luc DHONT

Le 30/05/2022 à 08:57, FANGAIN Marjorie a écrit :
>
> Hi,
>
> I’ve got also some problems with WFS layers for several months.
>
> I’ve created a ticket on github :
>
> https://github.com/3liz/lizmap-web-client/issues/2792
>
> Marjorie *FANGAIN*
>
> *De :* Lizmap <lizmap-bounces at lists.osgeo.org> *De la part de* Peter 
> Berger
> *Envoyé :* vendredi 27 mai 2022 11:26
> *À :* G. Wagner, Wagner-IT <info at wagner-it.de>; lizmap at lists.osgeo.org
> *Objet :* Re: [Lizmap] Publish WFS services in QGIS with Lizmap
>
> EXTERNAL EMAIL
> Original Sender: SRS0=UtB1=WD=lists.osgeo.org=lizmap-bounces at osgeo.org
>
> I made the same observation. On Windows 10 all WFS layers are well 
> displayed in Lizmap but not on a osgeolive linux installation with the 
> same QGIS file.
>
> Peter
>
> Von meinem iPhone gesendet
>
>
>
>     Am 27.05.2022 um 07:34 schrieb G. Wagner, Wagner-IT
>     <info at wagner-it.de>:
>
>     
>
>     Hi everyone,
>
>     I am trying to publish a WFS service integrated in QGIS with QGIS
>     Server/Lizmap (QGIS-Server 3.22.7, Lizmap 3.5.3).
>
>     The corresponding layer name is displayed in the Lizmap client but
>     no data is displayed. Or sometimes and only once in a zoom level.
>
>     The error message in the QGIS error log could fit to this (cache
>     problem?):
>
>     WARNING WFS[1497]: Cannot create temporary SpatiaLite cache.:
>     Cannot copy file to
>     /home/qgis/.local/share/QGIS/QGIS3/profiles/default/cache/wfsprovider/pid_1497/cache_1.sqlite:
>
>     Creating the directories
>     "/home/qgis/.local/share/QGIS/QGIS3/profiles/default/cache/wfsprovider"
>     with appropriate permissions does not change anything.
>
>     In the Apache error.log there is still the message:
>
>     QNetworkDiskCache::prepare() unable to open temporary file
>
>     In the Apache.conf is defined:
>
>             FcgidInitialEnv QGIS_SERVER_CACHE_DIRECTORY "/home/qgis/cache"
>
>     What am I doing wrong?
>
>     Greeting
>
>     Günter
>
>
> _______________________________________________
> Lizmap mailing list
> Lizmap at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/lizmap
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/lizmap/attachments/20220530/abc9063b/attachment-0001.htm>