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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:23:18 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:23:18 +0000 |
commit | 43a123c1ae6613b3efeed291fa552ecd909d3acf (patch) | |
tree | fd92518b7024bc74031f78a1cf9e454b65e73665 /src/database/sql/example_cli_test.go | |
parent | Initial commit. (diff) | |
download | golang-1.20-43a123c1ae6613b3efeed291fa552ecd909d3acf.tar.xz golang-1.20-43a123c1ae6613b3efeed291fa552ecd909d3acf.zip |
Adding upstream version 1.20.14.upstream/1.20.14upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/database/sql/example_cli_test.go')
-rw-r--r-- | src/database/sql/example_cli_test.go | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/src/database/sql/example_cli_test.go b/src/database/sql/example_cli_test.go new file mode 100644 index 0000000..1e297af --- /dev/null +++ b/src/database/sql/example_cli_test.go @@ -0,0 +1,84 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package sql_test + +import ( + "context" + "database/sql" + "flag" + "log" + "os" + "os/signal" + "time" +) + +var pool *sql.DB // Database connection pool. + +func Example_openDBCLI() { + id := flag.Int64("id", 0, "person ID to find") + dsn := flag.String("dsn", os.Getenv("DSN"), "connection data source name") + flag.Parse() + + if len(*dsn) == 0 { + log.Fatal("missing dsn flag") + } + if *id == 0 { + log.Fatal("missing person ID") + } + var err error + + // Opening a driver typically will not attempt to connect to the database. + pool, err = sql.Open("driver-name", *dsn) + if err != nil { + // This will not be a connection error, but a DSN parse error or + // another initialization error. + log.Fatal("unable to use data source name", err) + } + defer pool.Close() + + pool.SetConnMaxLifetime(0) + pool.SetMaxIdleConns(3) + pool.SetMaxOpenConns(3) + + ctx, stop := context.WithCancel(context.Background()) + defer stop() + + appSignal := make(chan os.Signal, 3) + signal.Notify(appSignal, os.Interrupt) + + go func() { + <-appSignal + stop() + }() + + Ping(ctx) + + Query(ctx, *id) +} + +// Ping the database to verify DSN provided by the user is valid and the +// server accessible. If the ping fails exit the program with an error. +func Ping(ctx context.Context) { + ctx, cancel := context.WithTimeout(ctx, 1*time.Second) + defer cancel() + + if err := pool.PingContext(ctx); err != nil { + log.Fatalf("unable to connect to database: %v", err) + } +} + +// Query the database for the information requested and prints the results. +// If the query fails exit the program with an error. +func Query(ctx context.Context, id int64) { + ctx, cancel := context.WithTimeout(ctx, 5*time.Second) + defer cancel() + + var name string + err := pool.QueryRowContext(ctx, "select p.name from people as p where p.id = :id;", sql.Named("id", id)).Scan(&name) + if err != nil { + log.Fatal("unable to execute search query", err) + } + log.Println("name=", name) +} |