improved cache

This commit is contained in:
partisan 2024-05-21 08:48:09 +02:00
parent 969dfe3fe3
commit 84d790a56e

89
text.go
View file

@ -26,9 +26,20 @@ func HandleTextSearch(w http.ResponseWriter, query, safe, lang string, page int)
const resultsPerPage = 10
cacheKey := CacheKey{Query: query, Page: page, Safe: safe, Lang: lang}
combinedResults := getResultsFromCacheOrFetch(cacheKey, query, safe, lang, page, resultsPerPage)
hasPrevPage := page > 1
hasNextPage := len(combinedResults) == resultsPerPage
displayResults(w, combinedResults, query, lang, time.Since(startTime).Seconds(), page, hasPrevPage, hasNextPage)
// Always check and cache the next page
go cacheNextPageIfNotCached(query, safe, lang, page+1, resultsPerPage)
}
func getResultsFromCacheOrFetch(cacheKey CacheKey, query, safe, lang string, page, resultsPerPage int) []TextSearchResult {
cacheChan := make(chan []TextSearchResult)
var combinedResults []TextSearchResult
var fromCache bool
go func() {
results, exists := resultsCache.Get(cacheKey)
@ -43,30 +54,55 @@ func HandleTextSearch(w http.ResponseWriter, query, safe, lang string, page int)
select {
case combinedResults = <-cacheChan:
if combinedResults != nil {
fromCache = true
} else {
combinedResults = fetchAndCacheResults(query, safe, lang, page, resultsPerPage)
if combinedResults == nil {
combinedResults = fetchResultsUntilFull(query, safe, lang, page, resultsPerPage)
resultsCache.Set(cacheKey, combinedResults)
}
case <-time.After(2 * time.Second):
log.Println("Cache check timeout")
combinedResults = fetchAndCacheResults(query, safe, lang, page, resultsPerPage)
combinedResults = fetchResultsUntilFull(query, safe, lang, page, resultsPerPage)
resultsCache.Set(cacheKey, combinedResults)
}
// Only pre-fetch and cache results for the next page if we fetched new results
if !fromCache {
go func() {
nextPageResults := fetchAndCacheResults(query, safe, lang, page+1, resultsPerPage)
resultsCache.Set(CacheKey{Query: query, Page: page + 1, Safe: safe, Lang: lang}, nextPageResults)
}()
return combinedResults
}
func cacheNextPageIfNotCached(query, safe, lang string, page, resultsPerPage int) {
cacheKey := CacheKey{Query: query, Page: page, Safe: safe, Lang: lang}
if _, exists := resultsCache.Get(cacheKey); !exists {
log.Printf("Next page %d not cached, caching now...", page)
nextPageResults := fetchResultsUntilFull(query, safe, lang, page, resultsPerPage)
resultsCache.Set(cacheKey, nextPageResults)
} else {
log.Printf("Next page %d already cached", page)
}
}
func fetchResultsUntilFull(query, safe, lang string, page, resultsPerPage int) []TextSearchResult {
var combinedResults []TextSearchResult
currentPage := 1
resultsNeeded := page * resultsPerPage
for len(combinedResults) < resultsNeeded {
results := fetchAndCacheResults(query, safe, lang, currentPage, resultsPerPage)
if len(results) == 0 {
break
}
combinedResults = append(combinedResults, results...)
currentPage++
}
hasPrevPage := page > 1
hasNextPage := len(combinedResults) == resultsPerPage
startIndex := (page - 1) * resultsPerPage
endIndex := startIndex + resultsPerPage
displayResults(w, combinedResults, query, lang, time.Since(startTime).Seconds(), page, hasPrevPage, hasNextPage)
if startIndex >= len(combinedResults) {
return []TextSearchResult{}
}
if endIndex > len(combinedResults) {
endIndex = len(combinedResults)
}
return combinedResults[startIndex:endIndex]
}
func fetchAndCacheResults(query, safe, lang string, page, resultsPerPage int) []TextSearchResult {
@ -113,24 +149,29 @@ func fetchAndCacheResults(query, safe, lang string, page, resultsPerPage int) []
mu.Unlock()
}
// Sort combinedResults by source priority: Google first, DuckDuckGo second, Qwant third
sort.SliceStable(combinedResults, func(i, j int) bool {
return sourceOrder(combinedResults[i].Source) < sourceOrder(combinedResults[j].Source)
})
// Paginate results
log.Printf("Fetched %d results for page %d", len(combinedResults), page)
return combinedResults
}
func paginateResults(results []TextSearchResult, page, resultsPerPage int) []TextSearchResult {
startIndex := (page - 1) * resultsPerPage
endIndex := startIndex + resultsPerPage
// Ensure startIndex and endIndex are within bounds
if startIndex >= len(combinedResults) {
log.Printf("Paginating results: startIndex=%d, endIndex=%d, totalResults=%d", startIndex, endIndex, len(results))
if startIndex >= len(results) {
return []TextSearchResult{}
}
if endIndex > len(combinedResults) {
endIndex = len(combinedResults)
if endIndex > len(results) {
endIndex = len(results)
}
return combinedResults[startIndex:endIndex]
return results[startIndex:endIndex]
}
func sourceOrder(source string) int {
@ -147,6 +188,10 @@ func sourceOrder(source string) int {
}
func displayResults(w http.ResponseWriter, results []TextSearchResult, query, lang string, elapsed float64, page int, hasPrevPage, hasNextPage bool) {
log.Printf("Displaying results for page %d", page)
log.Printf("Total results: %d", len(results))
log.Printf("Has previous page: %t, Has next page: %t", hasPrevPage, hasNextPage)
tmpl, err := template.New("text.html").Funcs(template.FuncMap{
"sub": func(a, b int) int {
return a - b