add support for HTTP Basic authentication

[tomkralidis]

As per http://hub.qgis.org/issues/16298

[luipir]

hi @tomkralidis

IMHO A Core plugin should use QGIS Authentication infrastructure, please have a look to:

http://docs.qgis.org/testing/en/docs/pyqgis_developer_cookbook/authentication.html

how to manage and save credentials in AuthDb. Thhere is also a sample code to move from httplib to QgsNetworkAccessManager. It can be used to inspire porting credential (and network management) to a uniform way.

[tomkralidis]

thanks @luipir. Will review and update.

[elpaso]

@tomkralidis if you want a "pythonic" synchronous interface to QgsNetworkAccessManager you can use this class: https://github.com/boundlessgeo/qgis-geoserver-plugin/blob/master/geoserverexplorer/geoserver/networkaccessmanager.py#L78 , it supports proxy QGIS config and auth manager.

[luipir]

@elpaso obviously is documented in http://docs.qgis.org/testing/en/docs/pyqgis_developer_cookbook/authentication.html#adapt-plugins-to-use-authentication-infrastructure ;)

[tomkralidis]

@luipir @elpaso thanks for the info. MetaSearch's HTTP handling is buried deep inside of OWSLib (which does the heavy lifting of the CSW handling we require for MetaSearch), so using something like QgsNetworkAccessManager will not be possible at this time.

For HTTP basic auth I have implemented QgsAuthManager to input/store credentials. Are there any examples of how to read HTTP Basic credentials?

[luipir]

you can find example in qgis-geoserver-plugin, but conceptually you have to get a AuthConfig (pointed by authid), from AuthManager. The AuthConfig will have credentials stored in it.

the main problem of this way to work, is that is not granted to be ported in QGIS3, due the secure problem to give access with python api to method to access sensible data (also when protected with a master pwd)

Give a look to NetworkAccessManager how expand credentials in a request URL starting from authid.

[elpaso]

@tomkralidis are you sure that you cannot config/patch owslib to use NetworkAccessManager to access the network? This is what we have done with other libraries, like gsconfig. I don't want to push anyone to use my class, but the "right" way to access the network from a QGIS plugin is to use QgsNetworkAccessManager, from that you get QGIS proxy and authentication support for free and you do need to worry about implementing it yourself like if you were using requests httlib urllib or any other python networking libraries that does not know about QGIS.

[tomkralidis]

@elpaso this would need to be an OWSLib enhancement and will take considerable time and effort.

Are folks ok if this pull request goes ahead as is and then implements networking correctly once OWSLib is updated?

[elpaso]

@tomkralidis yes, sure, go ahead.

[tomkralidis]

Travis error is unrelated, merging.

[tomkralidis]

@elpaso / @luipir merged. Thanks for the feedback and suggestions. FYI new issue to update MetaSearch's HTTP support filed in http://hub.qgis.org/issues/16304.