Mercurial > gemma
view pkg/imports/st.go @ 2455:54c9fe587fe6
Subdivide SQL function to prepare for improved error handling
The context of an error (e.g. the function in which it occured)
can be inferred by the database client. Not doing all in one
statement will render the context more meaningful.
author | Tom Gottfried <tom@intevation.de> |
---|---|
date | Fri, 01 Mar 2019 18:38:02 +0100 |
parents | c5bbe2409a52 |
children | 6b34d0fb4498 |
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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 imports import ( "context" "database/sql" "errors" "time" "gemma.intevation.de/gemma/pkg/models" ) type Stretch struct { Name string `json:"name"` From models.Isrs `json:"from"` To models.Isrs `json:"to"` ObjNam string `json:"objnam"` NObjNam *string `json:"nobjnam"` Source string `json:"source-organization"` Date models.Date `json:"date-info"` Countries models.UniqueCountries `json:"countries"` } const STJobKind JobKind = "st" type stJobCreator struct{} func init() { RegisterJobCreator(STJobKind, stJobCreator{}) } func (stJobCreator) Description() string { return "stretch" } func (stJobCreator) AutoAccept() bool { return false } func (stJobCreator) Create() Job { return new(Stretch) } func (stJobCreator) Depends() []string { return []string{ "stretches", } } const ( stDeleteSQL = ` DELETE FROM waterway.stretches WHERE staging_done AND name = ( SELECT name FROM waterway.stretches WHERE id = ( SELECT key from import.track_imports WHERE import_id = $1 AND relation = 'waterway.stretches'::regclass) AND NOT staging_done )` stStageDoneSQL = ` UPDATE waterway.stretches SET staging_done = true WHERE id IN ( SELECT key from import.track_imports WHERE import_id = $1 AND relation = 'waterway.stretches'::regclass)` stInsertSQL = ` WITH r AS ( SELECT isrsrange( ( $1::char(2), $2::char(3), $3::char(5), $4::char(5), $5::int), ( $6::char(2), $7::char(3), $8::char(5), $9::char(5), $10::int)) AS r ) INSERT INTO waterway.stretches ( name, stretch, area, objnam, nobjnam, date_info, source_organization ) VALUES ( $11, (SELECT r FROM r), ISRSrange_area( (SELECT r FROM r), (SELECT ST_Collect(CAST(area AS geometry)) FROM waterway.waterway_area)), $12, $13, $14, $15) RETURNING id` stInsertCountrySQL = ` INSERT INTO waterway.stretch_countries ( stretches_id, country_code ) VALUES ( $1, $2 )` ) // StageDone moves the imported stretch out of the staging area. func (stJobCreator) StageDone( ctx context.Context, tx *sql.Tx, id int64, ) error { if _, err := tx.ExecContext(ctx, stDeleteSQL, id); err != nil { return err } _, err := tx.ExecContext(ctx, stStageDoneSQL, id) return err } // CleanUp of a stretch import is a NOP. func (*Stretch) CleanUp() error { return nil } // Do executes the actual stretch import. func (st *Stretch) Do( ctx context.Context, importID int64, conn *sql.Conn, feedback Feedback, ) (interface{}, error) { start := time.Now() if st.Date.Time.IsZero() { st.Date = models.Date{Time: start} } feedback.Info("Storing stretch '%s'", st.Name) if len(st.Countries) == 0 { return nil, errors.New("List of countries is empty") } tx, err := conn.BeginTx(ctx, nil) if err != nil { return nil, err } defer tx.Rollback() insertCountryStmt, err := tx.PrepareContext(ctx, stInsertCountrySQL) if err != nil { return nil, err } var nobjnm sql.NullString if st.NObjNam != nil { nobjnm = sql.NullString{String: *st.NObjNam, Valid: true} } feedback.Info("Stretch from %s to %s.", st.From.String(), st.To.String()) var id int64 if err := tx.QueryRowContext( ctx, stInsertSQL, st.From.CountryCode, st.From.LoCode, st.From.FairwaySection, st.From.Orc, st.From.Hectometre, st.To.CountryCode, st.To.LoCode, st.To.FairwaySection, st.To.Orc, st.To.Hectometre, st.Name, st.ObjNam, nobjnm, st.Date.Time, st.Source, ).Scan(&id); err != nil { return nil, err } // store the associated countries. feedback.Info("Countries associated with stretch: %s.", st.Countries) for _, c := range st.Countries { if _, err := insertCountryStmt.ExecContext(ctx, id, c); err != nil { return nil, err } } if err := track(ctx, tx, importID, "waterway.stretches", id); err != nil { return nil, err } feedback.Info("Storing stretch '%s' took %s", st.Name, time.Since(start)) if err := tx.Commit(); err != nil { return nil, err } feedback.Info("Import of stretch was successful") summary := struct { Stretch string `json:"stretch"` }{ Stretch: st.Name, } return &summary, nil }