Adds an API which an algorithm can implement to support auto-setting
parameter values. This is designed to handle the case
of eg an algorithm which does a file format translation, where
it's desirable to default the output parameter value to an input
parameter value with a different extension.
This can now be done by implementing autogenerateParameterValues
in the algorithm, eg:
def autogenerateParameterValues(self, existingParameters, changedParameter, mode):
if changedParameter == self.INPUT:
input_file = existingParameters.get(self.INPUT)
if input_file:
input_path = Path(input_file)
if input_path.exists():
# auto set output parameter to same as input but with 'qgs' extension
return {self.OUTPUT: input_path.with_suffix('.qgs').as_posix()}
return {}
Works for both toolbox and batch modes for algorithms
When a profile tool is already opened, the output of a procssing is
not added to its layer tree. This is because it relies on a
`QgsLayerTreeRegistryBridge`. Indeed, `QgsLayerTreeRegistryBridge`
listens to the `QgsProject::legendLayersAdded()` signal in order to
update the elevation profile tree view. However this signal is not
triggered by the current logic in `Postprocessing.py`because
`QgsProject::addMaplayer` is called with `addToLegend` set to
False. Then, the layer is added to the tree by calling
`QgsLayerTreeGroup::insertChildNode`.
This issue is fixed by creating a
`QgsLayerTreeRegistryBridge::InsertionPoint` to set the insertion
point and then calling `QgsProject::addMaplayer` with `addToLegend`
set to True.
The older approach of storing parameters was insecure, and required
eval()ing the unchecked contents of the batch parameter file. This
is a security risk, as a malicious file could leak user information
or damage the system.
So,
- Switch to a newer ".batch" format which uses safe JSON objects
only for serializing parameter values.
- Allow loading the older .json files, but first show a warning
that they are a security risk and require to user to explicitly
agree to open the file
this has been done automatically with the following comand line
./scripts/3to4/3to4.py --only-qgis3-compatible-changes ./python/plugins/
./scripts/3to4/3to4.py --only-qgis3-compatible-changes ./tests/src/python/
