ZOO-Kernel configuration¶

Default main.cfg¶

An example main.cfg file is given here as reference.

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[headers]
X-Powered-By=ZOO@ZOO-Project

[main]
version=1.0.0
encoding=utf-8
dataPath=/var/data
tmpPath=/var/www/temp
cacheDir=/var/www/cache
sessPath=/tmp
serverAddress=http://localhost/cgi-bin/zoo_loader.cgi
lang=fr-FR,ja-JP
language=en-US
mapserverAddress=http://localhost/cgi-bin/mapserv.cgi
msOgcVersion=1.0.0
tmpUrl=http:/localhost/temp/
cors=false

[identification]
keywords=t,ZOO-Project, ZOO-Kernel,WPS,GIS
title=ZOO-Project demo instance
abstract= This is ZOO-Project, the Open WPS platform.
accessConstraints=none
fees=None

[provider]
positionName=Developer
providerName=GeoLabs SARL
addressAdministrativeArea=False
addressDeliveryPoint=1280, avenue des Platanes
addressCountry=fr
phoneVoice=+33467430995
addressPostalCode=34970
role=Dev
providerSite=http://geolabs.fr
phoneFacsimile=False
addressElectronicMailAddress=gerald@geolabs.fr
addressCity=Lattes
individualName=Gerald FENOY

Main section¶

The main.cfg [main] section parameters are explained bellow.

• version: Supported WPS version.
• encoding: Default encoding of WPS Responses.
• dataPath: Path to the directory where data files are stored (used to store mapfiles and data when MapServer support is activated).
• tmpPath: Path to the directory where temporary files are stored (such as ExecuteResponse when storeExecuteResponse is set to true).
• tmpUrl: URL to access the temporary files directory (cf. tmpPath).
• cacheDir: Path to the directory where cached request files [1] are stored (optional).
• serverAddress: URL to the ZOO-Kernel instance.
• mapservAddress: URL to the MapServer instance (optional).
• msOgcVersion: Version of all supported OGC Web Services output [2] (optional).
• lang: Supported natural languages separated by a coma (the first is the default one),
• cors: Define if the ZOO-Kernel should support Cross-Origin Resource Sharing. If this parameter is not defined, then the ZOO-Kernel won’t support CORS.
• servicePath: Define a specific location to search for services rather than using the ZOO-Kernel directory. If this parameter is not defined, then the ZOO-Kernel will search for services using its directory.
• libPath: (Optional) Path to a directory where the ZOO-kernel should search for service providers, e.g., shared libraries with service implementations (the serviceProvider parameter in the service configuration (.zcfg) file).
• memory: (Optional) can take the value load to ensure that the value field of the inputs data will be filled by the ZOO-Kernel or protected to have only the cache_file filled.
• handleText: (Optional) set it to true to get your Complex data nodes containing text not requiring a single CDATA node. Be aware that in case you use any HTML or XML there, you will then need to rebuild the string to get the original format of the text from your service code. In case you do not add handleText or set its value to true, you will simply need to use the value as it was provided in a single CDATA node provided in the Execute request.

In case you have activated the MapServer support, please refer to this specific section.

Identification and Provider¶

The [identification] and [provider] sections are not ZOO-Project specific. They provide OGC metadata [3] and should be set according to the XML Schema Document which encodes the parts of ISO 19115 used by the common ServiceIdentification and ServiceProvider sections of the GetCapabilities operation response, known as the service metadata XML document.

Details of the common OWS 1.1.0 ServiceIdentification section can be found in this XML Schema Document.

Details of the common OWS 1.1.0 ServiceProvider section can be found in this XML Schema Document.

Headers section¶

The [headers] section can be set in order to define a specific HTTP Response header, which will be used for every response. As an example, you can check http://zoo-project.org using curl command line tool and notice the specific header X-Powered-By: Zoo-Project@Trac.

In case you want to allow CORS support for POST requests coming from myhost.net, then you should define the following minimal parameters in this section:

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Access-Control-Allow-Origin=myhost.net
Access-Control-Allow-Methods=POST
Access-Control-Allow-Headers=content-type

curl section¶

The [curl] section is used on windows platform to specify, using the cainfo parameter, where is located the cacert.pem file on your machine. An example bellow is provided to illustrate sur a setting.

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[curl]
cainfo=./cacert.pem

env section¶

The [env] section can be used to store specific environment variables to be set prior the loading of Services Provider and Service execution.

A typical example is when a Service requires the access to a X server running on framebuffer, which takes to set the DISPLAY environnement variable, as follow:

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[env]
DISPLAY=:1

In case you have activated the OTB support, please refer to this specific section.

lenv section¶

The lenv section is used by the ZOO-Kernel to store runtime informations before the execution of a WPS service, it contains the following parameters:

• sid (r): The WPS Service unique identifier,
• status (rw): The current progress value ( a value between 0 and 100 in percent (%) ),
• cwd (r): The current working directory of ZOO-Kernel,
• message (rw): An error message used when SERVICE_FAILED is returned (optional),
• cookie (rw): The cookie to be returned to the client (for example for authentication purpose).
• file.pid (r): The file used by the ZOO-Kernel to store process identifier.
• file.sid (r): The file used by the ZOO-Kernel to store service identifier.
• file.responseInit (r): The file used by the ZOO-Kernel to store the initial (then final) WPS response.
• file.responseFinal (r): The file used by the ZOO-Kernel to temporary store the final WPS response.

renv section¶

The renv section is automatically created by the ZOO-Kernel before the execution of a WPS service, it contains all the environment variables available at runtime (so including the header fields in case it is used through http, refer to [https://tools.ietf.org/html/rfc3875 rfc3875] for more details).

senv section¶

The senv section can be used to store sessions information on the server side. Such information can then be accessed automatically from the Service if the server is requested using a valid cookie (as defined in lenv section). ZOO-Kernel will store the values set in the senv maps on disk, load it and dynamically replace its content to the one in the main.cfg. The senv section must contain the following parameter at least:

• XXX: The session unique identifier where XXX is the name included in the cookie which is returned.

For instance, adding the following in the Service source code :

conf["lenv"]["cookie"]="XXX=XXX1000000; path=/"
conf["senv"]={"XXX": "XXX1000000","login": "demoUser"}

means that ZOO-Kernel will create a file named sess_XXX1000000.cfg in the cacheDir directory, and will return the specified cookie to the client. Each time the client will request ZOO-Kernel using this cookie, it will automatically load the value stored before the Service execution.

Security section¶

The [security] section can be used to define what headers, the ZOO-Kernel has initially received in the request, should be passed to other servers for accessing resources (such as WMS, WFS, WCS or any other file passed as a reference). This section contains two parameters:

• attributes: The header to pass to other servers (such as Authorization, Cookie, User-Agent ...),
• hosts: The host for wich the restriction apply (can be “*” to forward header to every server or a coma separated list of host names, domain, IP).

Both parameters are mandatory.

Suppose you need to share Authorization, Cookie and User-Agent to every server for accessing ressources, then yo ucan use the following section definition:

[security]
attributes=Authorization,Cookie,User-Agent
hosts=*

In case only local servers require such header forwarding, you may use the following definition:

[security]
attributes=Authorization,Cookie,User-Agent
hosts=localhost,127.0.0.1

Optionaly, you can also define the shared url(s), meaning that even if the ressource requires authentication to be accessed, this authentifcation won’t be used to define the name for storing the file. Hence, two user with different authentication will use the same file as it is considerated as shared. You can find bellow a sample security section containing the shared parameter. In this example, every requests to access the coverage using the url defined in the shared parameter (myHost/cgi-bin/WCS_Server) will be shared between users.

[security]
attributes=Authorization,Cookie,User-Agent
hosts=localhost,127.0.0.1
shared=myHost/cgi-bin/WCS_Server

Database section¶

The database section allows to configure the ZOO-Kernel optional database support.

[database]
dbname=zoo_project
port=5432
user=username
host=127.0.0.1
type=PG
schema=public

This will generate strings to be passed to GDAL to connect the database server:

<type>:host=<host> port=<port>  user=<user> dbname=<dbname>

With the previous database section, it will give the following:

PG:"dbname=zoo_project host=127.0.0.1 port=5432 user=username"

Please refer to this section to learn how to setup the database.

Metadb section¶

The metadb section allows to configure the ZOO-Kernel to access the metadata information about WPS Services by using a PostgreSQL database in addition to the zcfg files.

[metadb]
dbname=zoo_metadb
port=5432
user=username
host=127.0.0.1
type=PG

This will generate strings to be passed to GDAL to connect the database server:

<type>:host=<host> port=<port>  user=<user> dbname=<dbname>

With the previous database section, it will give the following:

PG:"dbname=zoo_metadb host=127.0.0.1 port=5432 user=username"

Please refer to this section to learn how to setup the database.

Include section¶

The [include] section (optional) lists explicitely a set of service configuration files the the ZOO-Kernel should parse, e.g.,

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[include]
servicename1 = /my/service/repository/service1.zcfg
servicename2 = /my/service/repository/service2.zcfg

The [include] section may be used to control which services are exposed to particular user groups. While service configuration files (.zcfg) may be located in a common repository or in arbitrary folders, main.cfg files at different URLs may include different subsets of services.

When the ZOO-Kernel handles a request, it will first check if there is an [include] section in main.cfg and then search for other .zcfg files in the current working directory (CWD) and subdirectories. If an included service happens to be located in a CWD (sub)directory, it will be published by its name in the [include] section. For example, the service /[CWD]/name/space/myService.zcfg would normally be published as name.space.myService, but if it is listed in the [include] section it will be published simply as myService:

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[include]
myService =  /[CWD]/name/space/myService.zcfg

On the other hand, with

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[include]
myService =  /some/other/dir/myService.zcfg

there would be two distinct services published as myService and name.space.myService, respectively, with two different zcfg files.