lot of temp magick files created in temporary folder

问题

I am using the imagick library to resizing and cropping the images in a http handler. Which doesn't write anything in /tmp folder. But as i can a lot of these files are being created in that folder and it's size is growing on a daily basis and currently it's consuming around 90% of partition size. Moreover, i am not able to read their content also. So, why these files are being created and would they be delete after a while or do i need to manually delete them.

    -rw------- 1 ubuntu ubuntu   16M Feb 22 09:46 magick-d6ascKJV
    -rw------- 1 ubuntu ubuntu   16M Feb 22 09:46 magick-46ccZIfq
    -rw------- 1 ubuntu ubuntu  1.8M Feb 22 09:47 magick-vUET7vyh
    -rw------- 1 ubuntu ubuntu  1.8M Feb 22 09:47 magick-OLkGWTX8
    -rw------- 1 ubuntu ubuntu   15M Feb 22 09:48 magick-LNMV7YvE
    -rw------- 1 ubuntu ubuntu   16M Feb 22 09:49 magick-0LMYt6Kc
    -rw------- 1 ubuntu ubuntu   16M Feb 22 09:50 magick-ceNxX5CY
    -rw------- 1 ubuntu ubuntu   16M Feb 22 09:50 magick-nQ1M3y6I

Edit :

I am not using the following two lines in my http Handler. Reason being i couldn't find any explanation to do so. Moreover, the go http handler works fine. So, what is the purpose of these statements?

imagick.Initialize() 
defer imagick.Terminate()

I am assuming there would be some reason to include them in the code. So, in go http handler. Where it should be included inside func main() or inside serveHTTP ?

func main() {                                           
    myMux := http.NewServeMux()
    myMux.HandleFunc("/", serveHTTP)

    if err := http.ListenAndServe(":8085", myMux); err != nil {
        logFatal("Error when starting or running http server: %v", err)
    }       

}

func serveHTTP(w http.ResponseWriter, r *http.Request) {

}

回答1:

Temporary / intermediate files should be automatically cleaned-up by the calling ImageMagick thread. The pattern-behavior you are describing hints at a bug in the application using ImageMagick.

I would suggest...

Check error logs of application.
Evaluate error reporting of calling code.
Ensure proper imagick.Initialize & imagick.Terminate routines are called

And if nothing else works, use the environment variable MAGICK_TMPDIR to control where the imagemagick artifacts are written to.

Update

The imagick.Initialize wraps the underlying MagickCoreGenesis, and imagick.Terminate the MagickCoreTerminus routine. They are important for managing the environment in which ImageMagick operates. They should be called on the worker thread that will handle any ImageMagick tasks, so in your case, serveHTTP method. BUT it would not be optimal to perform such routines with every HTTP request, and an additional condition should be evaluated -- if possible.

func serveHTTP(w http.ResponseWriter, r *http.Request) {
   // if request will do image work
   imagick.Initialize() 
   defer imagick.Terminate()
   // ... image methods ...
   // end if
}

回答2:

You can set a cron which runs in a day or after an hour cleaning up your temp folder for all temporary magick files. you can use this on line command to delete all magick files as well

sudo find /tmp/ -name "magick-*" -type f -delete

回答3:

Actually it should be included in the func main() not in the func serveHTTP(). It is meant to be called once for a long running application and it solved my problem.

func main() {   

    imagick.Initialize() 
    defer imagick.Terminate()                                        
    myMux := http.NewServeMux()
    myMux.HandleFunc("/", serveHTTP)

    if err := http.ListenAndServe(":8085", myMux); err != nil {
        logFatal("Error when starting or running http server: %v", err)
    }       

}

func serveHTTP(w http.ResponseWriter, r *http.Request) {

}

来源：https://stackoverflow.com/questions/35550850/lot-of-temp-magick-files-created-in-temporary-folder

标签

ImageMagick

go-imagick