view cmd/octree2contour/store.go @ 742:fb9faf2c4f60

Clip contour lines against bounding area of sounding result.
author Sascha L. Teichmann <sascha.teichmann@intevation.de>
date Mon, 24 Sep 2018 13:14:49 +0200
parents 34ea9d5df653
children 271561dce2e6
line wrap: on
line source

package main

import (
	"database/sql"
	"time"

	"gemma.intevation.de/gemma/pkg/octree"
)

type result struct {
	h     float64
	lines octree.MultiLineStringZ
}

const (
	deleteSQL = `
DELETE FROM waterway.sounding_results_contour_lines
WHERE sounding_result_id IN (SELECT id
FROM waterway.sounding_results
WHERE bottleneck_id = $1 AND date_info = $2)
`
	insertSQL = `
INSERT INTO waterway.sounding_results_contour_lines
  (sounding_result_id, height, lines)
SELECT
  sr.id,
  $1,
  ST_Transform(
    ST_Translate(
      ST_Force3D(
        ST_CollectionExtract(
          ST_Force2D(
            ST_Intersection(
              ST_Transform(sr.area::geometry, $3::integer),
              ST_SetSRID(
                ST_GeomFromWKB($2), $3::integer))), 2)), 0.0, 0.0, $1::numeric),
  4326)::geography
FROM waterway.sounding_results sr
WHERE bottleneck_id = $4 AND date_info = $5
`
)

func store(
	all []result, epsg uint32,
	bottleneck string, date time.Time,
) error {

	return run(func(db *sql.DB) error {

		tx, err := db.Begin()
		if err != nil {
			return err
		}
		defer tx.Rollback()

		if _, err := tx.Exec(deleteSQL, bottleneck, date); err != nil {
			return err
		}

		stmt, err := tx.Prepare(insertSQL)
		if err != nil {
			return err
		}

		for _, r := range all {
			if _, err := stmt.Exec(
				r.h, r.lines.AsWKB(), epsg,
				bottleneck, date,
			); err != nil {
				return err
			}
		}

		return tx.Commit()
	})
}