FAQ - Frequently Asked Questions¶

General¶

Services and their usage in applications¶

F: I would like to know in which applications a specific WMS service is registered. Is there a way to achive that?

A: The information is provided in the Administration Backend as Source information.

Go to Sources and select a Source
Select a source via click on the Button Show Metadata and go to the tab Applications
You can see in which application the source is loaded
You can see whether the source is integrated as shared Instance or private Instance and wether it is activated or inactive
Via click on the application title or the source instance you can switch to the application or instance

If you prefer SQL you can take the WMS ID from the Source, replace the <id_of_the_wms> in the following SQL and run it:

        SELECT mb_core_application.* from mb_core_application, mb_core_layerset, mb_core_sourceinstance, mb_wms_wmsinstance, mb_wms_wmssource, mb_c           where
        -- applications and their layersets
        mb_core_application.id = mb_core_layerset.application_id and
        -- layersets and their instances
        mb_core_layerset.id = mb_core_sourceinstance.layerset and
        -- layerset-instances and wms-instance
ore_source
     mb_core_sourceinstance.id = mb_wms_wmsinstance.id and
        -- wms-instance and wms-source
        mb_wms_wmsinstance.wmssource = mb_wms_wmssource.id and
        -- wms-source and mb3-core source
        mb_wms_wmssource.id = mb_core_source.id and
        mb_core_source.id = <id_of_the_wms>;

app.php und app_dev.php: What purpose do they have?¶

Please take a look at the Details of the configuration of Mapbender, in chapter Production- and Development environment and Caching: app.php and app_dev.php.

For productive use you’ll use the app.php file. Only if you develop something (TWIG-files, CSS or JS-files) or for debugging, you’ll open Mapbender with the app_dev.php in developer mode. The developer mode provides more information and error messages.

What is this cache and when do I have to clear it?¶

Also for this question, please take a look at the Details of the configuration of Mapbender, in chapter Production- and Development environment and Caching: app.php and app_dev.php.

You’ll delete the contents of the mapbender/app/cache/ directory, not the folder itself. In detail the prod and - if present - the dev directory. It is no problem to delete these directories. When you run Mapbender again, new files will be stored again in the cache-directory.

Performance¶

Working with large WMS Services with many layers¶

Q: When I try to use a WMS Service with many layers (> 100) into an application, the configuration of the Layerset-Instance only takes and presents an incorrect amount of layers. In addition, the wms instance cannot be saved. Why?

A: To solve the problem, navigate to the php parameter max-input_vars. It defines the number of possible input variables. The default value is 1000 (depending on the php version). For a WMS with many layers, the number of input values is higher than the default value. You have to change the parameter to a higher value (e.g. 2000).

;; 1000 (default)
max_input_vars = 1000

My application cannot be duplicated¶

Q: I made a highly complex application and want to duplicate it, but it does not work.

A: A possible reason for this is that PHP does not allow a workflow with big files (YAML-export/import/etc.). The problem occurs especially in FastCGI. Just adjust the php parameter MaxRequestLen (you can do that in the configuration of FCGI).

# mod_fcgi.conf (Windows)
# set value to 2 MB
MaxRequestLen = 2000000

# fcgid.conf (Linux)
# set value to 2 MB
MaxRequestLen 2000000

Simultaneously, you should check the php values in php.ini:

max_execution_time = 240
memory_limit = 1024M
upload_max_filesize = 2M

Development and manual updates of modules¶

Q: How can I checkout a specific branch of the Mapbender module and test it? How can I revert this again? Does Composer help me with that?

A: Alternative 1: Go in the directory application/mapbender and checkout the specific branch. After your tests, checkout the original branch again. Do not forget to clear the cache directory (app/cache for Symfony 2, var/cache for the upcoming Symfony 3).

Alternative 2: Change the entry in composer: “mapbender/mapbender”: “dev-fix/meinfix” and do a Composer Update. Keep in mind that with that step all other vendor packages will be updated (that’s OK for developers). To go back, specify the original branch. In addition go back to application/mapbender and checkout the original branch by hand.

Installation¶

Attempted to call function “imagecreatefrompng”¶

F: I get an error when printing. I have looked into the logfiles (app/logs/prod.log) and found something like this:

CRITICAL - Uncaught PHP Exception Symfony\Component\Debug\Exception\UndefinedFunctionException:
"Attempted to call function "imagecreatefrompng"
from namespace "Mapbender\PrintBundle\Component"."
at /srv/mapbender-starter/application/mapbender/src/Mapbender/PrintBundle/Component/PrintService.php line 310

A: Please make sure you have installed the php-gd library.

Deprecation Notices at composer or bootstrap Script¶

Q: I get a deprecation warning when I call bootstrap or composer update:

Deprecation Notice: The callback ComposerBootstrap::checkConfiguration declared at
/srv//mapbender-starter/application/src/ComposerBootstrap.php accepts a Composer\Script\CommandEvent
but post-update-cmd events use a Composer\Script\Event instance.
Please adjust your type hint accordingly, see https://getcomposer.org/doc/articles/scripts.md#event-classes
in phar:///srv/mapbender-starter/composer.phar/src/Composer/EventDispatcher/EventDispatcher.php:290

A: This depends on the PHP version the system in running on and occurs on PHP versions < 7.

Oracle¶

Adjustments for Oracle database - point and comma¶

Q: I get an error when I run doctrine:schema:create on Oracle. Why? The error message is:

[Doctrine\DBAL\Exception\DriverException]
An exception occurred while executing
'CREATE TABLE mb_wms_wmsinstance (id NUMBER(10) NOT NULL,
                                  [...]
                                  PRIMARY KEY(id))':
ORA-01722: Invalid number

A: Probably Oracle can’t handle the decimal seperators and expects a comma instead of a point (for example 1,25 instead of 1.25). This can be adjusted with the following Snippet at the end of the config.yml (clear cache afterwards).

services:
  oracle.session.listener:
    class: Doctrine\DBAL\Event\Listeners\OracleSessionInit
    tags:
      - { name: doctrine.event_listener, event: postConnect }

This is a relation to a service-class provided by Doctrine. After the connection to Oracle, this class sets Session-Variables (ALTER SESSION) so that PHP and Oracle can work together in a better way.

Reasons might be: Language and regional settings of the operating system (for example Windows), settings of the Oracle-client, settings done during the installation of Oracle.

More Information at the Doctrine-page: http://www.doctrine-project.org/api/dbal/2.0/class-Doctrine.DBAL.Event.Listeners.OracleSessionInit.html

Which rights does the Mapbender user need for the Oracle database?¶

Create Sequence
Create Session
Create Table
Create Trigger
Create View

The access to an Oracle database is too slow¶

Q: Mapbender seems to have a poor performance while accessing Oracle databases. I noticed this because queries need more time than usual. Can I accelerate the process?

A: There are two parameters in php.ini which may tweak the performance of Mapbender with Oracle databases: oci8.max_persistent and oci8.default_prefetch. Adjust these parameters to:

oci8.max_persistent = 15
oci8.default_prefetch = 100000

Furthermore, change the respective persistent database connection parameter in config.yml to true.

persistent=true