Mercurial > gemma
view pkg/models/reproject.go @ 4969:5621586e7a54 fairway-marks-import
Avoid checking the same condition twice
An entry should either be UPDATEd or INSERTed, if it's not already
in the database. Thus simply INSERT if there was no UPDATE.
author | Tom Gottfried <tom@intevation.de> |
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date | Fri, 28 Feb 2020 17:55:55 +0100 |
parents | d753ce6cf588 |
children | 1222b777f51f |
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// This is Free Software under GNU Affero General Public License v >= 3.0 // without warranty, see README.md and license for details. // // SPDX-License-Identifier: AGPL-3.0-or-later // License-Filename: LICENSES/AGPL-3.0.txt // // Copyright (C) 2018 by via donau // – Österreichische Wasserstraßen-Gesellschaft mbH // Software engineering by Intevation GmbH // // Author(s): // * Sascha L. Teichmann <sascha.teichmann@intevation.de> package models import ( "context" "database/sql" ) const reprojectSQL = ` SELECT ST_X(p), ST_Y(p) FROM ST_Transform(ST_SetSRID(ST_MakePoint($1, $2), $3::integer), $4::integer) AS p` type Reprojector struct { stmt *sql.Stmt FromEPSG uint32 ToEPSG uint32 } func NewReprojector( ctx context.Context, conn *sql.Conn, fromEPSG, toEPSG uint32, ) (*Reprojector, error) { stmt, err := conn.PrepareContext(ctx, reprojectSQL) if err != nil { return nil, err } return &Reprojector{ stmt: stmt, FromEPSG: fromEPSG, ToEPSG: toEPSG, }, nil } func (r *Reprojector) Close() error { if s := r.stmt; s != nil { r.stmt = nil return s.Close() } return nil } func (r *Reprojector) Reproject( ctx context.Context, x, y float64, ) (v, w float64, err error) { err = r.stmt.QueryRowContext(ctx, x, y, r.FromEPSG, r.ToEPSG).Scan(&v, &w) return }