"forward declare" functions which will be patched when the processing
plugin starts, so that these are known and accessible during the PyQGIS
doc building. Also make these forward declared versions raise
QgsNotSupportedException, so that its clear why they aren't working
when the processing plugin hasn't started
Fixes https://github.com/qgis/pyqgis-api-docs-builder/issues/38
A shapefile can have a .cpg file to determine its encoding.
However, in processing, this file is not created when the
encoding is set to the magic "System" value.
This PR aims to propose to automatically determine the system
encoding using QT's codecForLocale.
So, even when using the magic "System" value, the cpg file
will be created with the true system encoding name.
Fixes#50603
[processing] Infrastructure for QgsMeshLayer to add processing algorithms, dataset group paramater and dataset time parameter to allow the user to easily choose a dataset.
CRS validation, regardless of the user's settings
This avoids hacks put in place in other parts of QGIS code or in plugins
to temporarily deactivate the CRS validation prompt, providing a supported,
stable method to indicate that when loading a particular layer no CRS
validation is required.
of main algorithm
Using code like:
buffered_layer = processing.run(..., context, feedback)['OUTPUT']
...
return {'OUTPUT': buffered_layer}
can cause issues if done as a sub-step of a larger processing algorithm. This
is because ownership of the generated layer is transferred to the caller
(Python) by processing.run. When the algorithm returns, Processing
attempts to move ownership of the layer from the context to the caller,
resulting in a crash.
(This is by design, because processing.run has been optimised for the
most common use case, which is one-off execution of algorithms as part
of a script, not as part of another processing algorithm. Accordingly
by design it returns layers and ownership to the caller, making things
easier for callers as they do not then have to resolve the layer reference
from the context object and handle ownership themselves)
This commit adds a new "is_child_algorithm" argument to processing.run.
For algorithms which are executed as sub-steps of a larger algorithm
is_child_algorithm should be set to True to avoid any ownership issues
with layers. E.g.
buffered_layer = processing.run(..., context, feedback, is_child_algorithm=True)['OUTPUT']
...
return {'OUTPUT': buffered_layer}
Replace with just f[idx]. Calling QgsFeature.attributes()
allocates a list of all attributes, which is inefficient
when only a single attribute value is needed.
processing options are changed
Make sure the algorithm dialogs use their own copy of algorithms,
instead of the copies owned by the processing registry. Opening
processing options triggers a full reload of providers, deleting
all existing algorithm instances from the registry first.
Adds processing.createAlgorithmDialog and
processing.execAlgorithmDialog. These methods can be used
to create and execute algorithm dialogs for a specified algorithm,
optionally pre-populated with a given set of (non-default) parameter
values.
