A website inspired by Last.fm that will keep track of your listening statistics
lastfm
music
statistics
oscarzwagers.nl
With work on the repos in go, there is now the ability to get all the data for an artist page like counts for the date ranges, most played songs and most played releases from an artist
1package database
2
3import (
4 "context"
5 "database/sql"
6 "strings"
7)
8
9func AppendMany[T any](args []any, values []T) []any {
10 for _, value := range values {
11 args = append(args, value)
12 }
13 return args
14}
15
16// QueryMany executes a query and returns a slice of results. It is a small helper function reducing
17// the boilerplate code needed to execute a query and scan the results. The scanFunc is used to scan
18// each row into a result.
19func QueryMany[T any](
20 ctx context.Context, db *sql.DB, query string, args []any, scanFunc func(*sql.Rows) (T, error),
21) ([]T, error) {
22 rows, err := db.QueryContext(ctx, query, args...)
23 if err != nil {
24 return nil, err
25 }
26 defer rows.Close()
27
28 var results []T
29 for rows.Next() {
30 result, err := scanFunc(rows)
31 if err != nil {
32 return nil, err
33 }
34 results = append(results, result)
35 }
36 return results, nil
37}
38
39// QueryOne executes a query and returns a single result. It is a small helper function reducing the
40// boilerplate code needed to execute a query and scan the results. The scanFunc is used to scan
41// the row into a result.
42func QueryOne[T any](
43 ctx context.Context, db *sql.DB, query string, args []any, scanFunc func(*sql.Rows) (T, error),
44) (T, error) {
45 rows, err := db.QueryContext(ctx, query, args...)
46 if err != nil {
47 return *new(T), err
48 }
49 defer rows.Close()
50
51 if !rows.Next() {
52 return *new(T), nil
53 }
54
55 return scanFunc(rows)
56}
57
58// Generates a string of placeholders for a SQL query. For example, if count is 3, the result will
59// be "?, ?, ?".
60func Placeholders(count int) string {
61 placeholders := make([]string, count)
62 for i := range placeholders {
63 placeholders[i] = "?"
64 }
65 return strings.Join(placeholders, ", ")
66}
67
68type Condition struct {
69 SQL string
70 Value any
71 Ok bool
72}
73
74// Takes a list of where strings and argument values together with a list of conditions. Those
75// conditions that are Ok will be added to the list of where strings and argument values. Useful
76// when having optional conditionals that used to filter a query.
77func Where(wheres []string, args []any, conditions ...Condition) ([]string, []any) {
78 for _, v := range conditions {
79 if v.Ok {
80 wheres = append(wheres, v.SQL)
81 args = append(args, v.Value)
82 }
83 }
84 return wheres, args
85}
86
87// Takes a list of SQL condition snippets and joins them with AND. If the list is empty, returns
88// TRUE.
89func WhereSQL(wheres []string) string {
90 where := "TRUE"
91 if len(wheres) > 0 {
92 where = strings.Join(wheres, " AND ")
93 }
94 return where
95}