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Diffstat (limited to 'internal/router/client-cache.go')
-rw-r--r--internal/router/client-cache.go318
1 files changed, 0 insertions, 318 deletions
diff --git a/internal/router/client-cache.go b/internal/router/client-cache.go
deleted file mode 100644
index 7c28b9e..0000000
--- a/internal/router/client-cache.go
+++ /dev/null
@@ -1,318 +0,0 @@
-package router
-
-import (
- "database/sql"
- "encoding/base64"
- "fmt"
- "log/slog"
- "strings"
- "sync"
-
- "golang.org/x/crypto/argon2"
-)
-
-type ClientCache struct {
- hashMap map[string]string
- hashMapMutex sync.RWMutex
-
- likePageMap map[string]map[string]struct{}
- viewPageMap map[string]map[string]struct{}
- pageMutexMap map[string]*sync.RWMutex
- pageMutexMapMutex sync.Mutex
-
- salt []byte
- db *sql.DB
-}
-
-func NewClientCache(db *sql.DB, salt []byte) (*ClientCache, error) {
- tx, err := db.Begin()
- if err != nil {
- return nil, fmt.Errorf("fail to init transaction with db to fill cache: %w", err)
- }
- slog.Debug("began db transaction", slog.String("method", "NewClientCache"))
-
- rows, err := tx.Query("select * from blog_likes;")
- if err != nil {
- tx.Rollback()
- slog.Debug("ended db transaction", slog.String("method", "NewClientCache"))
- return nil, fmt.Errorf("fail to query db for blog_likes to fill cache: %w", err)
- }
-
- likePageMap := make(map[string]map[string]struct{})
- viewPageMap := make(map[string]map[string]struct{})
- pageMutexMap := make(map[string]*sync.RWMutex)
-
- for rows.Next() {
- var pageRef string
- var userId []byte
- if err = rows.Scan(&pageRef, &userId); err != nil {
- tx.Rollback()
- return nil, fmt.Errorf("fail scanning blog_likes to fill cache: %w", err)
- }
- userIdString := base64.RawStdEncoding.EncodeToString(userId)
- if _, ok := likePageMap[pageRef]; !ok {
- likePageMap[pageRef] = make(map[string]struct{})
- viewPageMap[pageRef] = make(map[string]struct{})
- pageMutexMap[pageRef] = &sync.RWMutex{}
- }
- likePageMap[pageRef][userIdString] = struct{}{}
- viewPageMap[pageRef][userIdString] = struct{}{}
- }
-
- rows, err = tx.Query("select * from blog_views;")
- if err != nil {
- tx.Rollback()
- slog.Debug("ended db transaction", slog.String("method", "NewClientCache"))
- return nil, fmt.Errorf("fail to query db for blog_views to fill cache: %w", err)
- }
-
- for rows.Next() {
- var pageRef string
- var userId []byte
- if err = rows.Scan(&pageRef, &userId); err != nil {
- tx.Rollback()
- return nil, fmt.Errorf("fail scanning blog_views to fill cache: %w", err)
- }
- userIdString := base64.RawStdEncoding.EncodeToString(userId)
- if _, ok := viewPageMap[pageRef]; !ok {
- viewPageMap[pageRef] = make(map[string]struct{})
- pageMutexMap[pageRef] = &sync.RWMutex{}
- }
- viewPageMap[pageRef][userIdString] = struct{}{}
- }
-
- if err = tx.Commit(); err != nil {
- tx.Rollback()
- slog.Debug("ended db transaction", slog.String("method", "NewClientCache"))
- return nil, fmt.Errorf("fail to commit transaction in db: %w", err)
- }
- slog.Debug("ended db transaction", slog.String("method", "NewClientCache"))
-
- return &ClientCache{
- hashMap: make(map[string]string),
- likePageMap: likePageMap,
- viewPageMap: viewPageMap,
- pageMutexMap: pageMutexMap,
- salt: salt,
- db: db,
- }, nil
-}
-
-func (c *ClientCache) Close() error {
- tx, err := c.db.Begin()
- if err != nil {
- return fmt.Errorf("fail to init transaction with db to dump cache: %w", err)
- }
- slog.Debug("began db transaction in ClientCache.Close")
-
- if err = batchSave(tx, "blog_likes", c.likePageMap); err != nil {
- tx.Rollback()
- slog.Debug("ended db transaction in ClientCache.Close")
- return fmt.Errorf("fail to save blog_likes: %s", err)
- }
-
- if err = batchSave(tx, "blog_views", c.viewPageMap); err != nil {
- tx.Rollback()
- slog.Debug("ended db transaction in ClientCache.Close")
- return fmt.Errorf("fail to save blog_views: %s", err)
- }
-
- if err = tx.Commit(); err != nil {
- tx.Rollback()
- slog.Debug("ended db transaction in ClientCache.Close")
- return fmt.Errorf("fail to commit all the changes related to cache: %s", err)
- }
-
- slog.Debug("ended db transaction in ClientCache.Close")
- return nil
-}
-
-func (c *ClientCache) GetHash(id string) string {
- c.hashMapMutex.RLock()
- if val, ok := c.hashMap[id]; ok {
- c.hashMapMutex.RUnlock()
- slog.Debug("gave an old hash", slog.String("hash", val))
- return val
- }
- c.hashMapMutex.RUnlock()
-
- c.hashMapMutex.Lock()
- defer c.hashMapMutex.Unlock()
-
- if val, ok := c.hashMap[id]; ok {
- slog.Debug("gave a newly generated hash", slog.String("hash", val))
- return val
- }
-
- c.hashMap[id] = base64.RawStdEncoding.EncodeToString(argon2.IDKey([]byte(id), c.salt, 1, 64*1024, 4, 32))
- slog.Debug("generated hash", slog.String("hash", c.hashMap[id]))
- return c.hashMap[id]
-}
-
-func (c *ClientCache) getPageMutex(page string) *sync.RWMutex {
- c.pageMutexMapMutex.Lock()
- defer c.pageMutexMapMutex.Unlock()
-
- if mutex, ok := c.pageMutexMap[page]; ok {
- return mutex
- }
-
- c.pageMutexMap[page] = &sync.RWMutex{}
- return c.pageMutexMap[page]
-}
-
-func (c *ClientCache) GetLikeStatus(id string, page string) bool {
- page = strings.Clone(page)
-
- mutex := c.getPageMutex(page)
- mutex.RLock()
- defer mutex.RUnlock()
-
- if _, ok := c.likePageMap[page]; !ok {
- return false
- }
- _, ok := c.likePageMap[page][c.GetHash(id)]
- return ok
-}
-
-func (c *ClientCache) GetLikeCount(page string) int {
- page = strings.Clone(page)
-
- mutex := c.getPageMutex(page)
- mutex.RLock()
- defer mutex.RUnlock()
-
- if userSet, ok := c.likePageMap[page]; ok {
- return len(userSet)
- }
- return 0
-}
-
-func (c *ClientCache) LikeOn(id string, page string) (alreadyLiked bool) {
- page = strings.Clone(page)
- hash := c.GetHash(id)
-
- mutex := c.getPageMutex(page)
- mutex.Lock()
- defer mutex.Unlock()
-
- if userSet, ok := c.likePageMap[page]; ok {
- _, alreadyLiked = userSet[hash]
- c.likePageMap[page][hash] = struct{}{}
- return
- }
-
- c.likePageMap[page] = make(map[string]struct{})
- c.likePageMap[page][hash] = struct{}{}
- return
-}
-
-func (c *ClientCache) LikeOff(id string, page string) (alreadyUnliked bool) {
- page = strings.Clone(page)
- hash := c.GetHash(id)
-
- mutex := c.getPageMutex(page)
- mutex.Lock()
- defer mutex.Unlock()
-
- if _, ok := c.likePageMap[page]; !ok {
- return true
- }
- if _, ok := c.likePageMap[page][hash]; !ok {
- return true
- }
-
- delete(c.likePageMap[page], hash)
- return false
-}
-
-func (c *ClientCache) GetViewStatus(id string, page string) bool {
- page = strings.Clone(page)
-
- mutex := c.getPageMutex(page)
- mutex.RLock()
- defer mutex.RUnlock()
-
- if _, ok := c.viewPageMap[page]; !ok {
- return false
- }
- _, ok := c.viewPageMap[page][c.GetHash(id)]
- return ok
-}
-
-func (c *ClientCache) GetViewCount(page string) int {
- page = strings.Clone(page)
-
- mutex := c.getPageMutex(page)
- mutex.RLock()
- defer mutex.RUnlock()
-
- if userSet, ok := c.viewPageMap[page]; ok {
- return len(userSet)
- }
- return 0
-}
-
-func (c *ClientCache) View(id string, page string) {
- page = strings.Clone(page)
- hash := c.GetHash(id)
-
- mutex := c.getPageMutex(page)
- mutex.Lock()
- defer mutex.Unlock()
-
- if _, ok := c.viewPageMap[page]; !ok {
- c.viewPageMap[page] = make(map[string]struct{})
- }
- c.viewPageMap[page][hash] = struct{}{}
-}
-
-func batchSave(tx *sql.Tx, table string, pageMap map[string]map[string]struct{}) (err error) {
- if _, err = tx.Exec(fmt.Sprintf("delete from %s;", table)); err != nil {
- return fmt.Errorf("fail to truncate table %s: %w", table, err)
- }
-
- userIdBytes := make(map[string][]byte)
-
- sqlStatement := fmt.Sprintf(`
- INSERT OR IGNORE INTO %s (page_ref, user_id)
- VALUES %s(?, ?);
- `, table, strings.Repeat("(?, ?), ", 99))
- sqlStatementVars := make([]any, 0, 200)
-
- for pageRef, userSet := range pageMap {
- for userId := range userSet {
- if _, ok := userIdBytes[userId]; !ok {
- userIdBytes[userId], err = base64.RawStdEncoding.DecodeString(userId)
- if err != nil {
- slog.Warn("couldn't parse one of user hashes into bytes back", slog.String("hash", userId), slog.String("error", err.Error()))
- continue
- }
- }
-
- sqlStatementVars = append(sqlStatementVars, any(pageRef), any(userIdBytes[userId]))
- if len(sqlStatementVars) < 200 {
- continue
- }
-
- if _, err := tx.Exec(sqlStatement, sqlStatementVars...); err != nil {
- slog.Warn("couldn't insert blog stat pairs into db", slog.String("table", table), slog.String("error", err.Error()))
- }
-
- sqlStatementVars = make([]any, 0, 200)
- }
- }
-
- if len(sqlStatementVars) > 0 {
- sqlStatement = fmt.Sprintf(`
- INSERT OR IGNORE INTO %s (page_ref, user_id)
- VALUES %s(?, ?);
- `, table, strings.Repeat("(?, ?), ", len(sqlStatementVars)/2-1))
-
- if _, err := tx.Exec(sqlStatement, sqlStatementVars...); err != nil {
- slog.Warn("couldn't insert blog stat pairs into db", slog.String("table", table), slog.String("error", err.Error()))
- }
- }
-
- return nil
-}