Caching static resources

[juev]

From #221

We need to control the caching of static resources such as images, styles, and scripts. So that when files are changed, they immediately change at the front.

There are two ways to solve the problem:

• adding an E-Tag to static resource responses
• dynamically forming a file name, depending on its contents.

Examples of the second implementation are available in miniflux.

[juev]

😄

I asked ChatGPT how to add a tag, to which I received an answer:

package main

import (
    "crypto/md5"
    "encoding/hex"
    "net/http"
    "os"
    "io"
)

func main() {
    // Путь к статическому файлу
    staticFilePath := "path/to/static/file.txt"

    // Загрузка статического файла
    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        // Открытие статического файла
        file, err := os.Open(staticFilePath)
        if err != nil {
            http.Error(w, err.Error(), http.StatusInternalServerError)
            return
        }
        defer file.Close()

        // Создание хеша файла
        hash := md5.New()
        if _, err := io.Copy(hash, file); err != nil {
            http.Error(w, err.Error(), http.StatusInternalServerError)
            return
        }
        etag := hex.EncodeToString(hash.Sum(nil))

        // Устанавливаем заголовок ETag
        w.Header().Set("ETag", etag)

        // Проверяем If-None-Match заголовок
        if match := r.Header.Get("If-None-Match"); match == etag {
            w.WriteHeader(http.StatusNotModified)
            return
        }

        // Если не соответствует, отправляем содержимое файла
        http.ServeFile(w, r, staticFilePath)
    })

    // Старт сервера
    http.ListenAndServe(":8080", nil)
}

[juev]

After the research, I can say that using tags does not solve the problem when using the cache on the cloudflare side.

At the moment, I see only one solution: renaming the file depending on the time of its modification or its contents.