feat: support mongodb uri for connecting

Author: spy16

cli/cli.go

@@ -18,6 +18,7 @@ func Execute() {
 		cmdServe(),
 		cmdMigrate(),
 		cmdVersion(),
+		cmdShowConfigs(),
 	)
 
 	cmdx.SetHelp(rootCmd)

cli/config.go

@@ -1,8 +1,12 @@
 package cli
 
 import (
+	"fmt"
+	"os"
+
 	"github.com/odpf/salt/config"
 	"github.com/spf13/cobra"
+	"gopkg.in/yaml.v2"
 
 	"github.com/odpf/entropy/internal/server"
 	"github.com/odpf/entropy/internal/store/mongodb"
@@ -12,9 +16,24 @@ import (
 
 const configFlag = "config"
 
+func cmdShowConfigs() *cobra.Command {
+	return &cobra.Command{
+		Use:   "configs",
+		Short: "Display configurations currently loaded",
+		Run: func(cmd *cobra.Command, args []string) {
+			cfg, err := loadConfig(cmd)
+			if err != nil {
+				fmt.Printf("failed to read configs: %v\n", err)
+				os.Exit(1)
+			}
+			_ = yaml.NewEncoder(os.Stdout).Encode(cfg)
+		},
+	}
+}
+
 // Config contains the application configuration
 type Config struct {
-	DB       mongodb.DBConfig      `mapstructure:"db"`
+	DB       mongodb.Config        `mapstructure:"db"`
 	Log      logger.LogConfig      `mapstructure:"log"`
 	Service  server.Config         `mapstructure:"service"`
 	NewRelic metric.NewRelicConfig `mapstructure:"newrelic"`

cli/migrate.go

@@ -31,8 +31,8 @@ func cmdMigrate() *cobra.Command {
 	return cmd
 }
 
-func runMigrations(ctx context.Context, cfg mongodb.DBConfig) error {
-	mongoStore, err := mongodb.New(&cfg)
+func runMigrations(ctx context.Context, cfg mongodb.Config) error {
+	mongoStore, err := mongodb.Connect(cfg)
 	if err != nil {
 		return err
 	}

cli/serve.go

@@ -50,7 +50,7 @@ func runServer(c Config) error {
 		return err
 	}
 
-	mongoStore, err := mongodb.New(&c.DB)
+	mongoStore, err := mongodb.Connect(c.DB)
 	if err != nil {
 		return err
 	}

entropy.yaml

@@ -2,14 +2,17 @@ service:
   host: localhost
   port: 8080
 
+# MongoDB configurations
+# Refer https://www.mongodb.com/docs/manual/reference/connection-string/ for the
+# uri format.
 db:
-  host: localhost
+  uri: "mongodb://localhost:27017/?connectTimeoutMS=1000&socketTimeoutMS=1000&readPreference=secondaryPreferred"
   name: entropy
-  port: 27017
+  ping_timeout: 3s
 
 newrelic:
   enabled: false
-  appname: entropy-dev
+  appname: Entropy
   license: ____LICENSE_STRING_OF_40_CHARACTERS_____
 
 log:

internal/store/mongodb/db.go

@@ -2,42 +2,37 @@ package mongodb
 
 import (
 	"context"
-	"fmt"
 	"time"
 
 	"go.mongodb.org/mongo-driver/mongo"
 	"go.mongodb.org/mongo-driver/mongo/options"
 )
 
-// DBConfig contains the database configuration
-type DBConfig struct {
-	Host string `mapstructure:"host" default:"localhost"`
-	Port string `mapstructure:"port" default:"27017"`
+// Config contains the database configurations.
+type Config struct {
+	// URI should be valid MongodDB connection string.
+	// https://www.mongodb.com/docs/manual/reference/connection-string/
+	URI string `mapstructure:"uri" default:"mongodb://localhost:27017"`
+
+	// Name should be the name of the database to use.
 	Name string `mapstructure:"name" default:"entropy"`
-}
 
-// New returns the database instance
-func New(config *DBConfig) (*mongo.Database, error) {
-	uri := fmt.Sprintf(
-		"mongodb://%s:%s/%s",
-		config.Host,
-		config.Port,
-		config.Name,
-	)
+	// PingTimeout decides the maximum time to wait for ping response.
+	PingTimeout time.Duration `mapstructure:"ping_timeout" default:"3s"`
+}
 
-	client, err := mongo.Connect(context.TODO(), options.Client().ApplyURI(uri))
+// Connect returns the database instance
+func Connect(cfg Config) (*mongo.Database, error) {
+	client, err := mongo.Connect(context.TODO(), options.Client().ApplyURI(cfg.URI))
 	if err != nil {
 		return nil, err
 	}
 
-	pingCtx, pingCancel := context.WithTimeout(context.TODO(), time.Second*5)
+	pingCtx, pingCancel := context.WithTimeout(context.TODO(), cfg.PingTimeout)
 	defer pingCancel()
-
-	err = client.Ping(pingCtx, nil)
-
-	if err != nil {
+	if err := client.Ping(pingCtx, nil); err != nil {
 		return nil, err
 	}
 
-	return client.Database(config.Name), nil
+	return client.Database(cfg.Name), nil
 }