Add absences table and basic queries

* Add migration scripts
* Add queries to add, get and list absences
* Add tests for the above
* Add function to get the date of the next Monday

Also fixes potential bug in the build where the output binary would be
written to a file called `./bin` rather than a file named after the
source directory in a _directory_ called `./bin`.

Dockerfile

@@ -1,7 +1,7 @@
 FROM golang:1.19-buster as builder
 WORKDIR /app
 COPY . .
-RUN go build -buildvcs=false -o ./bin ./cmd/...
+RUN mkdir ./bin; go build -buildvcs=false -o ./bin ./cmd/...
 
 FROM ubuntu:22.04 as litestream
 WORKDIR /download

absences.go

@@ -1 +1,98 @@
 package themis
+
+import (
+	"context"
+	"fmt"
+	"time"
+)
+
+func (s *Store) AddAbsence(ctx context.Context, session time.Time, userId string) error {
+	if session.Weekday() != time.Monday {
+		return fmt.Errorf("not a monday")
+	}
+
+	tx, err := s.db.Begin()
+	if err != nil {
+		return fmt.Errorf("failed to begin transaction: %w", err)
+	}
+	defer tx.Commit() //nolint:errcheck
+
+	stmt, err := s.db.PrepareContext(ctx, "INSERT INTO absences (session_date, userid) VALUES (?, ?)")
+	if err != nil {
+		return fmt.Errorf("failed to prepare absence query: %w", err)
+	}
+
+	_, err = stmt.ExecContext(ctx, session.Format("2006-01-02"), userId)
+	if err != nil {
+		return fmt.Errorf("failed to insert absence: %w", err)
+	}
+
+	return nil
+}
+
+func (s *Store) GetAbsentees(ctx context.Context, session time.Time) ([]string, error) {
+	tx, err := s.db.Begin()
+	if err != nil {
+		return nil, fmt.Errorf("failed to begin transaction: %w", err)
+	}
+	defer tx.Commit() //nolint:errcheck
+
+	stmt, err := s.db.PrepareContext(ctx, `SELECT userid FROM absences WHERE session_date = ?`)
+	if err != nil {
+		return nil, fmt.Errorf("failed to prepare query: %w", err)
+	}
+
+	rows, err := stmt.QueryContext(ctx, session.Format("2006-01-02"))
+	if err != nil {
+		return nil, fmt.Errorf("failed to execute query: %w", err)
+	}
+
+	absentees := make([]string, 0)
+	for rows.Next() {
+		var abs string
+		err = rows.Scan(&abs)
+		if err != nil {
+			return nil, fmt.Errorf("failed to scan row: %w", err)
+		}
+
+		absentees = append(absentees, abs)
+	}
+
+	return absentees, nil
+}
+
+type Foo struct {
+	session_date string
+	userid       string
+}
+
+func (s *Store) GetSchedule(ctx context.Context, from, to time.Time) ([]Foo, error) {
+	tx, err := s.db.Begin()
+	if err != nil {
+		return nil, fmt.Errorf("failed to begin transaction: %w", err)
+	}
+	defer tx.Commit() //nolint:errcheck
+
+	stmt, err := s.db.PrepareContext(ctx, `SELECT session_date, userid FROM absences WHERE session_date BETWEEN ? AND ? ORDER BY session_date ASC`)
+	if err != nil {
+		return nil, fmt.Errorf("failed to prepare query: %w", err)
+	}
+
+	rows, err := stmt.QueryContext(ctx, from.Format("2006-01-02"), to.Format("2006-01-02"))
+	if err != nil {
+		return nil, fmt.Errorf("failed to execute query: %w", err)
+	}
+
+	schedule := make([]Foo, 0)
+	for rows.Next() {
+		var foo Foo
+		err = rows.Scan(&foo.session_date, &foo.userid)
+		if err != nil {
+			return nil, fmt.Errorf("failed to scan row: %w", err)
+		}
+
+		schedule = append(schedule, foo)
+	}
+
+	return schedule, nil
+}

absences_test.go

@@ -0,0 +1,41 @@
+package themis
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestAddAbsence(t *testing.T) {
+	store, err := NewStore(fmt.Sprintf(TEST_CONN_STRING_PATTERN, "TestAddAbsence"))
+	require.NoError(t, err)
+
+	now := NextMonday()
+	assert.NoError(t, store.AddAbsence(context.TODO(), now, "foobarbaz"))
+	absentees, err := store.GetAbsentees(context.TODO(), now)
+	assert.NoError(t, err)
+	assert.Equal(t, 1, len(absentees))
+	assert.Equal(t, "foobarbaz", absentees[0])
+
+	assert.NoError(t, store.AddAbsence(context.TODO(), now, "foobarbaz"))
+	absentees, err = store.GetAbsentees(context.TODO(), now)
+	assert.NoError(t, err)
+	assert.Equal(t, 1, len(absentees))
+}
+
+func TestGetSchedule(t *testing.T) {
+	store, err := NewStore(fmt.Sprintf(TEST_CONN_STRING_PATTERN, "TestGetSchedule"))
+	require.NoError(t, err)
+
+	now := NextMonday()
+
+	_ = store.AddAbsence(context.TODO(), now.Add(7*24*time.Hour), "foobar")
+
+	schedule, err := store.GetSchedule(context.TODO(), now, now.Add(2*7*24*time.Hour))
+	assert.NoError(t, err)
+	assert.Equal(t, 1, len(schedule))
+}

cmd/themis-server/main.go

@@ -437,6 +437,9 @@ func main() {
 				log.Error().Err(err).Msg("failed to respond to interaction")
 			}
 		},
+		"schedule": func(s *discordgo.Session, i *discordgo.InteractionCreate) {
+			store.GetSchedule(ctx, time.Now(), time.Now().Add(4*7*24*time.Hour))
+		},
 	}
 
 	registerHandlers(discord, handlers)

migrations/20231113_add_absences.down.sql

@@ -0,0 +1 @@
+DROP TABLE absences;

migrations/20231113_add_absences.up.sql

@@ -0,0 +1,5 @@
+CREATE TABLE IF NOT EXISTS absences (
+    session_date TEXT, -- 2006-11-23
+    userid TEXT,
+    UNIQUE(session_date, userid) ON CONFLICT IGNORE
+);

time.go

@@ -0,0 +1,13 @@
+package themis
+
+import "time"
+
+var now func() time.Time
+
+func init() {
+	now = time.Now
+}
+
+func NextMonday() time.Time {
+	return now().AddDate(0, 0, int((8-now().Weekday())%7))
+}

time_test.go

@@ -0,0 +1,46 @@
+package themis
+
+import (
+	"reflect"
+	"testing"
+	"time"
+)
+
+func TestNextMonday(t *testing.T) {
+	tests := []struct {
+		name string
+		seed string
+		want string
+	}{
+		{
+			name: "on monday",
+			seed: "2023-11-13T15:04:05Z07:00",
+			want: "2023-11-13T15:04:05Z07:00",
+		},
+		{
+			name: "on sunday",
+			seed: "2023-11-12T15:04:05Z07:00",
+			want: "2023-11-13T15:04:05Z07:00",
+		},
+		{
+			name: "on tuesday",
+			seed: "2023-11-14T15:04:05Z07:00",
+			want: "2023-11-20T15:04:05Z07:00",
+		},
+		{
+			name: "on saturday",
+			seed: "2023-11-18T15:04:05Z07:00",
+			want: "2023-11-20T15:04:05Z07:00",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			seedt, _ := time.Parse(time.RFC3339, tt.seed)
+			now = func() time.Time { return seedt }
+			wantt, _ := time.Parse(time.RFC3339, tt.want)
+			if got := NextMonday(); !reflect.DeepEqual(got, wantt) {
+				t.Errorf("NextMonday() = %v, want %v", got, wantt)
+			}
+		})
+	}
+}