Add logging to database service

cmd/webapp/main.go

@@ -4,13 +4,17 @@ import (
 	"log"
 	"tacitus/http"
 	"tacitus/postgres"
+	"tacitus/osutil"
 )
 
 func main() {
+	logger := osutil.NewLogger()
+	logger.Utc = true
 	s := http.NewServer()
 	db := postgres.NewClient()
 	db.Name = "gdax"
 	db.User = "gdax"
+	db.SetLogger(logger)
 	if err := db.Open(); err != nil {
 		log.Panic(err)
 	}

http/trade_handler.go

@@ -20,7 +20,7 @@ type tradesResponse struct {
 func (t *TradeHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	paths := strings.Split(r.URL.Path, "/")
 
-	if len(paths) < 4 && !tacitus.ValidProduct(paths[3]) {
+	if len(paths) < 3 || !tacitus.ValidProduct(paths[3]) {
 		errorResp(w, tacitus.Error("Invalid product"))
 		return
 	}

osutil/logger_service.go

@@ -20,7 +20,7 @@ type LoggerService struct {
 }
 
 func NewLogger() *LoggerService {
-	l := Logger{}
+	l := LoggerService{}
 
 	l.DateFormat = time.RFC3339Nano
 	l.Stderr = true
@@ -68,7 +68,7 @@ func (l *LoggerService) Info(format string, params ...interface{}) {
 	}
 }
 
-func (l * Logger) formattedTime() string {
+func (l *LoggerService) formattedTime() string {
 	t := time.Now()
 
 	if l.Utc {

postgres/client.go

@@ -19,6 +19,7 @@ type Client struct {
 
 	tradeService TradeService
 
+	logger tacitus.Logger
 	db *sql.DB
 }
 
@@ -30,6 +31,11 @@ func NewClient() *Client {
 	return &c
 }
 
+func (c *Client) SetLogger(logger tacitus.Logger) {
+	c.logger = logger
+	c.tradeService.Logger = logger
+}
+
 func (c *Client) Open() error {
 	buf := bytes.Buffer{}
 	tmpl, _ := template.New("conn").Parse(connStr)
@@ -37,17 +43,32 @@ func (c *Client) Open() error {
 
 	db, err := sql.Open("postgres", buf.String())
 	if err != nil {
+		c.log(`Failed to connect to postgres. params=%v`, buf.String())
 		return err
 	}
 
 	if err = db.Ping(); err != nil {
+		c.log(`Failed to connect to postgres. params=%v`, buf.String())
 		return err
 	}
+	c.log(`Conntected to postgres. params="%v"`, buf.String())
 
 	c.db = db
 	return nil
 }
 
+func (c *Client) Close() error {
+	err := c.db.Close()
+	c.log("Closed postgres connection")
+	return err
+}
+
 func (c *Client) TradeService() tacitus.TradeService {
 	return &c.tradeService
 }
+
+func (c *Client) log(format string, params ...interface{}) {
+	if c.logger != nil {
+		c.logger.Info(format, params...)
+	}
+}

postgres/trade_service.go

@@ -28,15 +28,18 @@ const (
 )
 
 type TradeService struct {
+	Logger tacitus.Logger
 	client *Client
 }
 
 func (t *TradeService) Trade(id int) (*tacitus.Trade, error) {
 	var tr tacitus.Trade
 
+	t.logQuery(trade_find, id)
 	row := t.client.db.QueryRow(trade_find, id)
 	if err := row.Scan(&tr.Id, &tr.TradeId, &tr.Product, &tr.Price, &tr.Size, &tr.Buy,
 		&tr.Sell, &tr.Timestamp); err != nil {
+		t.logError(trade_find, err, id)
 
 		return nil, err
 	}
@@ -47,10 +50,13 @@ func (t *TradeService) Trade(id int) (*tacitus.Trade, error) {
 func (t *TradeService) TradeByTradeId(id int, prod string) (*tacitus.Trade, error) {
 	var tr tacitus.Trade
 
+	t.logQuery(trade_find_trade_id, id, prod)
 	row := t.client.db.QueryRow(trade_find_trade_id, id, prod)
 	if err := row.Scan(&tr.Id, &tr.TradeId, &tr.Product, &tr.Price,
 		&tr.Size, &tr.Buy, &tr.Sell, &tr.Timestamp); err != nil {
 
+		t.logError(trade_find_trade_id, err, id, prod)
+
 		return nil, err
 	}
 
@@ -59,9 +65,13 @@ func (t *TradeService) TradeByTradeId(id int, prod string) (*tacitus.Trade, erro
 
 func (t *TradeService) CreateTrade(trade *tacitus.Trade) error {
 	var id int
-	res := t.client.db.QueryRow(trade_insert, trade.TradeId, trade.Product,
-		trade.Price, trade.Size, trade.Buy, trade.Sell, trade.Timestamp)
+	params := []interface{}{trade.TradeId, trade.Product, trade.Price,
+		trade.Size, trade.Buy, trade.Sell, trade.Timestamp}
+
+	t.logQuery(trade_insert, params...)
+	res := t.client.db.QueryRow(trade_insert, params...)
 	if err := res.Scan(&id); err != nil {
+		t.logError(trade_insert, err, params...)
 		return err
 	}
 
@@ -71,14 +81,22 @@ func (t *TradeService) CreateTrade(trade *tacitus.Trade) error {
 }
 
 func (t *TradeService) DeleteTrade(id int) {
-	t.client.db.Exec(trade_delete, id)
+	t.logQuery(trade_delete, id)
+
+	_, err := t.client.db.Exec(trade_delete, id)
+	if err != nil{
+		t.logError(trade_delete, err, id)
+	}
 }
 
 func (t *TradeService) TradesInDateRange(product string, start,
 	end time.Time) ([]tacitus.Trade, error) {
 
+	t.logQuery(trade_in_date_range, product, start, end)
 	rows, err := t.client.db.Query(trade_in_date_range, product, start, end)
 	if err != nil {
+		t.logError(trade_in_date_range, err, product, start, end)
+
 		return nil, err
 	}
 
@@ -86,8 +104,11 @@ func (t *TradeService) TradesInDateRange(product string, start,
 }
 
 func (t *TradeService) FirstTrades(product string, limit int) ([]tacitus.Trade, error) {
+	t.logQuery(trade_first, product, limit)
 	rows, err := t.client.db.Query(trade_first, product, limit)
 	if err != nil {
+		t.logError(trade_first, err, product, limit)
+
 		return nil, err
 	}
 
@@ -95,8 +116,11 @@ func (t *TradeService) FirstTrades(product string, limit int) ([]tacitus.Trade,
 }
 
 func (t *TradeService) LastTrades(product string, limit int) ([]tacitus.Trade, error) {
+	t.logQuery(trade_last, product, limit)
 	rows, err := t.client.db.Query(trade_last, product, limit)
 	if err != nil {
+		t.logError(trade_last, err, product, limit)
+
 		return nil, err
 	}
 
@@ -104,8 +128,11 @@ func (t *TradeService) LastTrades(product string, limit int) ([]tacitus.Trade, e
 }
 
 func (t *TradeService) TradesAfter(product string, id, limit int) ([]tacitus.Trade, error) {
+	t.logQuery(trade_after, product, id, limit)
 	rows, err := t.client.db.Query(trade_after, product, id, limit)
 	if err != nil {
+		t.logError(trade_after, err, product, id, limit)
+
 		return nil, err
 	}
 
@@ -114,8 +141,11 @@ func (t *TradeService) TradesAfter(product string, id, limit int) ([]tacitus.Tra
 }
 
 func (t *TradeService) TradesBefore(product string, id, limit int) ([]tacitus.Trade, error) {
+	t.logQuery(trade_before, product, id, limit)
 	rows, err := t.client.db.Query(trade_before, product, id, limit)
 	if err != nil {
+		t.logError(trade_before, err, product, id, limit)
+
 		return nil, err
 	}
 
@@ -123,6 +153,20 @@ func (t *TradeService) TradesBefore(product string, id, limit int) ([]tacitus.Tr
 
 }
 
+func (t *TradeService) logQuery(sql string, params ...interface{}) {
+	t.log(`SQL query="%v" params="%v"`, sql, params)
+}
+
+func (t *TradeService) logError(sql string, err error, params ...interface{}) {
+	t.log(`SQL FAIL query="%v" params="%v" error="%v"`, sql, params, err)
+}
+
+func (t *TradeService) log(format string, params ...interface{}) {
+	if t.Logger != nil {
+		t.Logger.Info(format, params...)
+	}
+}
+
 func deserializeTrades(rows *sql.Rows) ([]tacitus.Trade, error) {
 	defer rows.Close()