Support PATH type with geo::LineString

This commit is contained in:
kestred 2017-03-10 17:20:51 -07:00
parent efbf30c4fe
commit e07b7b04e4
2 changed files with 57 additions and 1 deletions

View File

@ -268,6 +268,13 @@ types. The driver currently supports the following conversions:
</td>
<td>BOX</td>
</tr>
<tr>
<td>
<a href="https://github.com/georust/rust-geo">geo::LineString&lt;f64&gt;</a>
(<a href="#optional-features">optional</a>)
</td>
<td>PATH</td>
</tr>
</tbody>
</table>
@ -340,3 +347,11 @@ support is provided optionally by the `with-geo` feature, which adds `ToSql` and
[BOX](https://www.postgresql.org/docs/9.4/static/datatype-geometric.html#AEN6883)
support is provided optionally by the `with-geo` feature, which adds `ToSql` and `FromSql` implementations for `geo`'s `Bbox` type.
### PATH type
[PATH](https://www.postgresql.org/docs/9.4/static/datatype-geometric.html#AEN6912)
support is provided optionally by the `with-geo` feature, which adds `ToSql` and `FromSql` implementations for `geo`'s `LineString` type.
Paths converted from LineString are always treated as "open" paths. Use the
[pclose](https://www.postgresql.org/docs/8.2/static/functions-geometry.html#FUNCTIONS-GEOMETRY-FUNC-TABLE)
geometric function to insert a closed path.

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@ -1,7 +1,7 @@
extern crate geo;
use postgres_protocol::types;
use self::geo::{Bbox, Point};
use self::geo::{Bbox, LineString, Point};
use std::error::Error;
use types::{FromSql, ToSql, IsNull, Type};
@ -59,3 +59,44 @@ impl ToSql for Bbox<f64> {
accepts!(Type::Box);
to_sql_checked!();
}
impl FromSql for LineString<f64> {
fn from_sql(_: &Type, raw: &[u8]) -> Result<Self, Box<Error + Sync + Send>> {
if raw.len() < 5 {
return Err("invalid message length".into());
}
// let _ = types::bool_from_sql(&raw[0..1])?; // is path open or closed
let n_points = types::int4_from_sql(&raw[1..5])? as usize;
let raw_points = &raw[5..raw.len()-1];
if raw_points.len() != 16 * n_points {
return Err("invalid message length".into());
}
let mut points = Vec::with_capacity(n_points);
for n in 0..n_points {
let x = types::float8_from_sql(&raw[n..n+8])?;
let y = types::float8_from_sql(&raw[n+8..n+16])?;
points.push(Point::new(x, y));
}
Ok(LineString(points))
}
accepts!(Type::Path);
}
impl ToSql for LineString<f64> {
fn to_sql(&self, _: &Type, out: &mut Vec<u8>) -> Result<IsNull, Box<Error + Sync + Send>> {
let closed = false; // always encode an open path from LineString
types::bool_to_sql(closed, out);
types::int4_to_sql(self.0.len() as i32, out);
for point in &self.0 {
types::float8_to_sql(point.x(), out);
types::float8_to_sql(point.y(), out);
}
Ok(IsNull::No)
}
accepts!(Type::Path);
to_sql_checked!();
}