✨ Cache link meta with database

pkg/internal/database/migrator.go

@@ -0,0 +1,20 @@
+package database
+
+import (
+	"git.solsynth.dev/hydrogen/dealer/pkg/internal/models"
+	"gorm.io/gorm"
+)
+
+var AutoMaintainRange = []any{
+	&models.LinkMeta{},
+}
+
+func RunMigration(source *gorm.DB) error {
+	if err := source.AutoMigrate(
+		AutoMaintainRange...,
+	); err != nil {
+		return err
+	}
+
+	return nil
+}

pkg/internal/database/source.go

@@ -0,0 +1,28 @@
+package database
+
+import (
+	"github.com/rs/zerolog/log"
+	"github.com/samber/lo"
+	"github.com/spf13/viper"
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+	"gorm.io/gorm/schema"
+)
+
+var C *gorm.DB
+
+func NewSource() error {
+	var err error
+
+	dialector := postgres.Open(viper.GetString("database.dsn"))
+	C, err = gorm.Open(dialector, &gorm.Config{NamingStrategy: schema.NamingStrategy{
+		TablePrefix: viper.GetString("database.prefix"),
+	}, Logger: logger.New(&log.Logger, logger.Config{
+		Colorful:                  true,
+		IgnoreRecordNotFoundError: true,
+		LogLevel:                  lo.Ternary(viper.GetBool("debug.database"), logger.Info, logger.Silent),
+	})})
+
+	return err
+}

pkg/internal/models/link.go

@@ -3,6 +3,7 @@ package models
 type LinkMeta struct {
 	BaseModel
 
+	Entry       string  `json:"entry_id" gorm:"uniqueIndex"`
 	Icon        string  `json:"icon"`
 	URL         string  `json:"url"`
 	Image       *string `json:"image"`

pkg/internal/services/link_expander.go

@@ -1,6 +1,9 @@
 package services
 
 import (
+	"crypto/md5"
+	"encoding/hex"
+	"git.solsynth.dev/hydrogen/dealer/pkg/internal/database"
 	"git.solsynth.dev/hydrogen/dealer/pkg/internal/models"
 	"github.com/gocolly/colly"
 	"github.com/rs/zerolog/log"
@@ -10,7 +13,29 @@ import (
 	"time"
 )
 
+func RetrieveLinkMetaFromCache(target string) (models.LinkMeta, error) {
+	hash := md5.Sum([]byte(target))
+	entry := hex.EncodeToString(hash[:])
+	var meta models.LinkMeta
+	if err := database.C.Where("entry = ?", entry).First(&meta).Error; err != nil {
+		return meta, err
+	}
+	return meta, nil
+}
+
+func SaveLinkMetaToCache(target string, meta models.LinkMeta) error {
+	hash := md5.Sum([]byte(target))
+	entry := hex.EncodeToString(hash[:])
+	meta.Entry = entry
+	return database.C.Save(&meta).Error
+}
+
 func LinkExpand(target string) (*models.LinkMeta, error) {
+	if cache, err := RetrieveLinkMetaFromCache(target); err == nil {
+		log.Debug().Str("url", target).Msg("Expanding link... hit cache")
+		return &cache, nil
+	}
+
 	c := colly.NewCollector(
 		colly.UserAgent("SolarBot/1.0"),
 		colly.MaxDepth(3),
@@ -75,6 +100,7 @@ func LinkExpand(target string) (*models.LinkMeta, error) {
 	})
 
 	c.OnScraped(func(r *colly.Response) {
+		_ = SaveLinkMetaToCache(target, *meta)
 		log.Debug().Str("url", target).Msg("Expanding link... finished")
 	})