instrumented absences with opentelemetry

absences.go

@@ -2,15 +2,30 @@ package themis
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"time"
 
 	"github.com/rs/zerolog/log"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	semconv "go.opentelemetry.io/otel/semconv/v1.24.0"
+	"go.opentelemetry.io/otel/trace"
 )
 
 func (s *Store) AddAbsence(ctx context.Context, session time.Time, userId string) error {
+	ctx, span := tracer.Start(ctx, "add_absence", trace.WithAttributes(
+		semconv.DBSystemSqlite,
+		semconv.DBSQLTable("absences"),
+		semconv.DBOperation("insert"),
+		attribute.String("user_id", userId),
+		attribute.String("session_date", session.Format(time.DateOnly)),
+	))
+	defer span.End()
+
 	if session.Weekday() != time.Monday {
 		log.Debug().Ctx(ctx).Msg(fmt.Sprintf("%s is not a monday", session))
+		span.RecordError(errors.New(fmt.Sprintf("%s is not a monday", session)))
 		return fmt.Errorf("not a monday")
 	}
 
@@ -21,17 +36,23 @@ func (s *Store) AddAbsence(ctx context.Context, session time.Time, userId string
 
 	tx, err := s.db.Begin()
 	if err != nil {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to begin transaction")
 		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 {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to prepare absence query")
 		return fmt.Errorf("failed to prepare absence query: %w", err)
 	}
 
 	_, err = stmt.ExecContext(ctx, session.Format(time.DateOnly), userId)
 	if err != nil {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to insert absence")
 		return fmt.Errorf("failed to insert absence: %w", err)
 	}
 
@@ -39,20 +60,34 @@ func (s *Store) AddAbsence(ctx context.Context, session time.Time, userId string
 }
 
 func (s *Store) GetAbsentees(ctx context.Context, session time.Time) ([]string, error) {
+	ctx, span := tracer.Start(ctx, "get_absentees", trace.WithAttributes(
+		semconv.DBSystemSqlite,
+		semconv.DBSQLTable("absences"),
+		semconv.DBOperation("select"),
+		attribute.String("session_date", session.Format(time.DateOnly)),
+	))
+	defer span.End()
+
 	log.Debug().Ctx(ctx).Time("session", session).Msg("getting list of absentees")
 	tx, err := s.db.Begin()
 	if err != nil {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to begin transaction")
 		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 {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to prepare query")
 		return nil, fmt.Errorf("failed to prepare query: %w", err)
 	}
 
 	rows, err := stmt.QueryContext(ctx, session.Format(time.DateOnly))
 	if err != nil {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to execute query")
 		return nil, fmt.Errorf("failed to execute query: %w", err)
 	}
 
@@ -74,23 +109,38 @@ func (s *Store) GetAbsentees(ctx context.Context, session time.Time) ([]string,
 type Schedule map[string][]string
 
 func (s *Store) GetSchedule(ctx context.Context, from, to time.Time) (Schedule, error) {
+	ctx, span := tracer.Start(ctx, "add_absence", trace.WithAttributes(
+		semconv.DBSystemSqlite,
+		semconv.DBSQLTable("absences"),
+		semconv.DBOperation("select"),
+		attribute.String("from", from.Format(time.DateOnly)),
+		attribute.String("to", to.Format(time.DateOnly)),
+	))
+	defer span.End()
+
 	log.Debug().Ctx(ctx).Time("from", from).Time("to", to).Msg("getting next sessions schedule")
 	schedule := make(Schedule)
 	initSchedule(schedule, from, to)
 
 	tx, err := s.db.Begin()
 	if err != nil {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to begin transaction")
 		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 {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to prepare query")
 		return nil, fmt.Errorf("failed to prepare query: %w", err)
 	}
 
 	rows, err := stmt.QueryContext(ctx, from.Format(time.DateOnly), to.Format(time.DateOnly))
 	if err != nil {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, "failed to execute query")
 		return nil, fmt.Errorf("failed to execute query: %w", err)
 	}
 
@@ -99,6 +149,8 @@ func (s *Store) GetSchedule(ctx context.Context, from, to time.Time) (Schedule,
 		var user string
 		err = rows.Scan(&date, &user)
 		if err != nil {
+			span.RecordError(err)
+			span.SetStatus(codes.Error, "failed to scan row")
 			return nil, fmt.Errorf("failed to scan row: %w", err)
 		}
 

cmd/themis-server/main.go

@@ -20,6 +20,7 @@ import (
 	_ "github.com/mattn/go-sqlite3"
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
+	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/propagation"
@@ -1033,5 +1034,6 @@ func initTracing(db *sql.DB) {
 		sdktrace.WithResource(res),
 	)
 
+	otel.SetTracerProvider(tp)
 	tracer = tp.Tracer("themis")
 }

store.go

@@ -14,11 +14,20 @@ import (
 	"github.com/golang-migrate/migrate/v4/source/iofs"
 	_ "github.com/mattn/go-sqlite3"
 	"github.com/rs/zerolog/log"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/trace"
 )
 
 //go:embed migrations/*.sql
 var migrations embed.FS
 
+var tracer trace.Tracer
+
+func init() {
+	tp := otel.GetTracerProvider()
+	tracer = tp.Tracer("themis")
+}
+
 type Store struct {
 	db *sql.DB
 }