Algorithms and other processing code should use this method
(instead of dataobjects.getLayerFromString) to
retrieve layers from a string, as it considers the processing
context and allows resolving strings to temporarily stored layers.
This permits processing models to function correctly when
intermediate results are stored as memory layers. Subsequent
model algorithms can then access these temporary layers as inputs.
All temporary layers will be removed when the context object
is destroyed after the model algorithm is run.
Also
- simplify and add tests
- remove large memory leak (persistant store of all non-project layers)
- remove broken support for direct loading postgres/virtual layers
by string (Python version was very broken and would never match
a postgres/virtual layer)
Tags are used while searching in the toolbox. This should help with
finding algorithms when the exact name is not known, eg
you could search for "envelope" or "bounds" and find the
'Polygon from Layer Extent' algorithm.
At the moment it's quite hard to discover algorithms which exist
when you don't know what their called and have to instead search
for every possible naming variant which could exist...
Since the layer has more complete knowledge of the crs (ie, when
provider could not determine crs and user has selected it from
the list), and also better knowledge of layer fields (virtual
fields, joined fields) we should use these rather than the
provider methods.
* Remove deprecated Qgis::WKBType and API cleanup
Renames QgsWKBTypes to QgsWkbTypes
Replaces usage of the enums:
* Qgis::WKBType with QgsWkbTypes::Type
* Qgis::GeometryType with QgsWkbTypes::GeometryType
Their values should be forward compatible (a fact that was already
explited up to now by casting between the types)
Renames some SSLxxx to SslXxx and URIxxx to UriXxx
* Fix build warnings and simplify type handling
* Add a fixer to rewrite imports
* The forgotten rebase conflictThe forgotten rebase conflicts
* QgsDataSourcURI > QgsDataSourceUri
* QgsWKBTypes > QgsWkbTypes
* Qgis.WKBGeom > QgsWkbTypes.Geom
* Further python fixes
* Guess what... Qgis::wkbDimensions != QgsWkbTypes::wkbDimensions
* Fix tests
* Python 3 updates
* [travis] pull request caching cannot be disabled
so at least use it in r/w mode
* Fix python3 print in plugins
This algorithm joins all connected parts of MultiLineString
geometries into single LineString geometries.
If any parts of the input MultiLineString geometries are not
connected, the resultant geometry will be a MultiLineString
containing any lines which could be merged and any non-connected
line parts.
