Merge pull request #200 from ChristianBeilschmidt/ogr-set-attributes

OGR Layer: Set Attribute Filter & Set Spatial Filter as Rectangle
georust · Jul 28, 2021 · 8facee4 · 8facee4
2 parents 46d8a0a + 05c99b5
commit 8facee4
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Showing 3 changed files with 83 additions and 2 deletions.
diff --git a/CHANGES.md b/CHANGES.md
@@ -170,8 +170,13 @@ let mut dataset = driver
 
   - <https://github.com/georust/gdal/pull/186>
 
-  - Wrapper functions for `OGR_F_GetFieldAs…` methods
-    - <https://github.com/georust/gdal/pull/199>
+- Wrapper functions for `OGR_F_GetFieldAs…` methods
+
+  - <https://github.com/georust/gdal/pull/199>
+
+- Wrapper functions for `OGR_L_SetAttributeFilter` and `OGR_L_SetSpatialFilterRect`
+
+  - <https://github.com/georust/gdal/pull/200>
 
 ## 0.7.1
 

diff --git a/src/vector/layer.rs b/src/vector/layer.rs
@@ -164,6 +164,11 @@ impl<'a> Layer<'a> {
         unsafe { gdal_sys::OGR_L_SetSpatialFilter(self.c_layer, geometry.c_geometry()) };
     }
 
+    /// Set a spatial rectangle filter on this layer by specifying the bounds of a rectangle.
+    pub fn set_spatial_filter_rect(&mut self, min_x: f64, min_y: f64, max_x: f64, max_y: f64) {
+        unsafe { gdal_sys::OGR_L_SetSpatialFilterRect(self.c_layer, min_x, min_y, max_x, max_y) };
+    }
+
     /// Clear spatial filters set on this layer.
     pub fn clear_spatial_filter(&mut self) {
         unsafe { gdal_sys::OGR_L_SetSpatialFilter(self.c_layer, null_mut()) };
@@ -330,6 +335,32 @@ impl<'a> Layer<'a> {
             gdal_sys::OGR_L_ResetReading(self.c_layer);
         }
     }
+
+    /// Set a new attribute query that restricts features when using the feature iterator.
+    ///
+    /// Parameters:
+    /// - `query` in restricted SQL WHERE format
+    ///
+    pub fn set_attribute_filter(&self, query: &str) -> Result<()> {
+        let c_str = CString::new(query)?;
+        let rv = unsafe { gdal_sys::OGR_L_SetAttributeFilter(self.c_layer, c_str.as_ptr()) };
+
+        if rv != OGRErr::OGRERR_NONE {
+            return Err(GdalError::OgrError {
+                err: rv,
+                method_name: "OGR_L_SetAttributeFilter",
+            });
+        }
+
+        Ok(())
+    }
+
+    /// Clear the attribute filter set on this layer
+    pub fn clear_attribute_filter(&self) {
+        unsafe {
+            gdal_sys::OGR_L_SetAttributeFilter(self.c_layer, null_mut());
+        }
+    }
 }
 
 pub struct FeatureIterator<'a> {

diff --git a/src/vector/vector_tests/mod.rs b/src/vector/vector_tests/mod.rs
@@ -573,6 +573,10 @@ mod tests {
 
         layer.clear_spatial_filter();
         assert_eq!(layer.features().count(), 21);
+
+        // test filter as rectangle
+        layer.set_spatial_filter_rect(26.1017, 44.4297, 26.1025, 44.4303);
+        assert_eq!(layer.features().count(), 7);
     }
 
     #[test]
@@ -690,4 +694,45 @@ mod tests {
     //         }
     //     });
     // }
+
+    #[test]
+    fn test_set_attribute_filter() {
+        with_layer("roads.geojson", |mut layer| {
+            // check number without calling any function
+            assert_eq!(layer.features().count(), 21);
+
+            // check if clearing does not corrupt anything
+            layer.clear_attribute_filter();
+            assert_eq!(layer.features().count(), 21);
+
+            // apply actual filter
+            layer.set_attribute_filter("highway = 'primary'").unwrap();
+
+            assert_eq!(layer.features().count(), 1);
+            assert_eq!(
+                layer
+                    .features()
+                    .next()
+                    .unwrap()
+                    .field_as_string_by_name("highway")
+                    .unwrap()
+                    .unwrap(),
+                "primary"
+            );
+
+            // clearing and check again
+            layer.clear_attribute_filter();
+
+            assert_eq!(layer.features().count(), 21);
+
+            // force error
+            assert_eq!(
+                layer.set_attribute_filter("foo = bar"),
+                Err(GdalError::OgrError {
+                    err: gdal_sys::OGRErr::OGRERR_CORRUPT_DATA,
+                    method_name: "OGR_L_SetAttributeFilter",
+                })
+            );
+        });
+    }
 }