Refactor api fmt.println with geth logger

Author: MartiTM

cmd/crawler/api.go

@@ -9,6 +9,7 @@ import (
 
 	_ "modernc.org/sqlite"
 
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/node-crawler/pkg/api"
 	"github.com/ethereum/node-crawler/pkg/apidb"
 	"github.com/ethereum/node-crawler/pkg/crawlerdb"
@@ -58,7 +59,7 @@ func startAPI(ctx *cli.Context) error {
 		return err
 	}
 	if shouldInit {
-		fmt.Println("DB did not exist, init")
+		log.Info("DB did not exist, init")
 		if err := apidb.CreateDB(nodeDB); err != nil {
 			return err
 		}
@@ -104,7 +105,7 @@ func transferNewNodes(crawlerDB, nodeDB *sql.DB) error {
 			// happen. We will still try again.
 			return fmt.Errorf("error inserting nodes: %w", err)
 		}
-		fmt.Printf("%d nodes inserted\n", len(nodes))
+		log.Info("Nodes inserted", "len", len(nodes))
 	}
 
 	crawlerDBTx.Commit()
@@ -123,7 +124,7 @@ func newNodeDeamon(wg *sync.WaitGroup, crawlerDB, nodeDB *sql.DB) {
 	for {
 		err := transferNewNodes(crawlerDB, nodeDB)
 		if err != nil {
-			fmt.Printf("error transferring new nodes: %s\n", err)
+			log.Error("Failure in transferring new nodes", "err", err)
 			time.Sleep(retryTimeout)
 			retryTimeout *= 2
 			continue

pkg/api/api.go

@@ -9,6 +9,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/gorilla/mux"
 	lru "github.com/hashicorp/golang-lru"
 )
@@ -39,7 +40,7 @@ func (a *Api) dropCacheLoop() {
 	// Drop the cache every 2 minutes
 	ticker := time.NewTicker(2 * time.Minute)
 	for range ticker.C {
-		fmt.Println("Dropping Cache")
+		log.Info("Dropping Cache")
 		c, err := lru.New(256)
 		if err != nil {
 			panic(err)
@@ -54,7 +55,7 @@ func (a *Api) HandleRequests(wg *sync.WaitGroup) {
 	router.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) { w.Write([]byte("Hello")) })
 	router.HandleFunc("/v1/dashboard", a.handleDashboard).Queries("filter", "{filter}")
 	router.HandleFunc("/v1/dashboard", a.handleDashboard)
-	fmt.Println("Starting API on:", a.address)
+	log.Info("Starting API", "address", a.address)
 	http.ListenAndServe(a.address, router)
 }
 
@@ -143,7 +144,7 @@ func (a *Api) cachedOrQuery(prefix, query string, whereArgs []interface{}) []cli
 		var err error
 		result, err = clientQuery(a.db, query, whereArgs...)
 		if err != nil {
-			fmt.Println(err)
+			log.Error("Failure in the query", "err", err)
 		}
 	}
 	return result
@@ -189,7 +190,7 @@ func (a *Api) handleDashboard(rw http.ResponseWriter, r *http.Request) {
 	// Where
 	where, whereArgs, err := addFilterArgs(vars)
 	if err != nil {
-		fmt.Println(err)
+		log.Error("Failure when adding filter to the query", "err", err)
 		return
 	}
 	if whereArgs != nil {

pkg/apidb/database.go

@@ -2,11 +2,11 @@ package apidb
 
 import (
 	"database/sql"
-	"fmt"
 	"sort"
 	"strings"
 	"time"
 
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/node-crawler/pkg/crawlerdb"
 	"github.com/ethereum/node-crawler/pkg/vparser"
 )
@@ -39,7 +39,7 @@ func CreateDB(db *sql.DB) error {
 }
 
 func InsertCrawledNodes(db *sql.DB, crawledNodes []crawlerdb.CrawledNode) error {
-	fmt.Printf("Writing nodes to db: %v\n", len(crawledNodes))
+	log.Info("Writing nodes to db", "len", len(crawledNodes))
 
 	tx, err := db.Begin()
 	if err != nil {
@@ -121,7 +121,7 @@ func InsertCrawledNodes(db *sql.DB, crawledNodes []crawlerdb.CrawledNode) error
 }
 
 func DropOldNodes(db *sql.DB, minTimePassed time.Duration) error {
-	fmt.Printf("Dropping all nodes older than: %v\n", minTimePassed)
+	log.Info("Dropping nodes", "older than", minTimePassed)
 	oldest := time.Now().Add(-minTimePassed)
 	tx, err := db.Begin()
 	if err != nil {
@@ -136,6 +136,6 @@ func DropOldNodes(db *sql.DB, minTimePassed time.Duration) error {
 		return err
 	}
 	affected, _ := res.RowsAffected()
-	fmt.Printf("Dropped %v nodes\n", affected)
+	log.Info("Nodes drop", "affected", affected)
 	return tx.Commit()
 }