Resize cov duab ntawm ya

Hauv yuav luag txhua lub vev xaib uas siv cov duab, yuav tsum tau tsim cov ntawv luam me me ntawm cov duab no, thiab feem ntau muaj ntau hom ntawv rau cov duab ntxiv.
Ntxiv qhov ntev tshiab rau daim ntawv thov uas twb muaj lawm kuj ua rau qee qhov mob taub hau. Yog li lub luag haujlwm:

Hom phiaj

Cia peb pom cov npe ntawm cov kev xav tau:

• Tsim cov duab ntxiv ntawm ib hom ntawv ya yam tsis tau qhia txog kev ua haujlwm ntxiv rau hauv daim ntawv thov txhua lub sijhawm thaum daim ntawv thov muaj nyob;
• Cov duab ntxiv tsis tas yuav tsum tau tsim rau txhua qhov kev thov;
• Tshem tawm lub peev xwm los tsim cov duab ntxiv ntawm cov hom tsis tau teev tseg.

Kuv yuav piav qhia lub ntsiab lus kawg, vim nws me ntsis contradicts thawj taw tes. Yog tias peb ua cov cim ntawm ib qho duab qhib, ces muaj peev xwm ua rau muaj kev tawm tsam ntawm qhov chaw los ntawm kev tsim ntau tus neeg thov kom hloov pauv cov duab rau hauv ib qho tsis kawg ntawm cov qauv, yog li qhov tsis zoo no yuav tsum raug kaw.

nginx installation configuration

Txhawm rau daws cov kev xav tau saum toj no peb xav tau cov txheej txheem nginx hauv qab no:

• ngx_http_image_filter_module - rau resizing cov duab;
• ngx_http_proxy_module - rau caching;
• ngx_http_secure_link_module - tiv thaiv spam;

Cov qauv ngx_http_image_filter_module и ngx_http_secure_link_module tsis tau teeb tsa los ntawm lub neej ntawd, yog li lawv yuav tsum tau teev nyob rau ntawm theem teeb tsa kev teeb tsa nginx:

phoinix@phoinix-work:~/src/nginx-0.8.29
$ ./configure --with-http_secure_link_module --with-http_image_filter_module


nginx configuration

Peb ntxiv ib qho tshiab rau peb tus tswv tsev configuration qhov chaw thiab general cache parameters:

...
    proxy_cache_path /www/myprojects/cache levels=1:2 keys_zone=image-preview:10m;
...
    server {
...
        location ~ ^/preview/([cir])/(.+) {
        # Тип операции
            set                         $oper $1;
        # Параметры изображения и путь к файлу
            set                         $remn $2;
        # Проксируем на отдельный хост
            proxy_pass                  http://myproject.ru:81/$oper/$remn;
            proxy_intercept_errors      on;
            error_page                  404 = /preview/404;
        # Кеширование
            proxy_cache                 image-preview;
            proxy_cache_key             "$host$document_uri";
        # 200 ответы кешируем на 1 день
            proxy_cache_valid           200 1d;
        # остальные ответы кешируем на 1 минуту
            proxy_cache_valid           any 1m;
        }
        
        # Возвращаем ошибку
        location = /preview/404 {
            internal;
            default_type                image/gif;
            alias                       /www/myprojects/image/noimage.gif;
        }
...
    }
...


Peb kuj ntxiv ib tus tswv tsev tshiab rau kev teeb tsa:

server {
    server_name                     myproject.ru;
    listen                          81;

    access_log                      /www/myproject.ru/logs/nginx.preview.access_log;
    error_log                       /www/myproject.ru/logs/nginx.preview.error_log info;

    # Указываем секретное слово для md5
    secure_link_secret              secret;

    # Ошибки отправляем она отдельный location
    error_page                      403 404 415 500 502 503 504 = @404;

    # location Для фильтра size
    location ~ ^/i/[^/]+/(.+) {
        
        # грязный хак от Игоря Сысоева *
        alias                       /www/myproject.ru/images/$1;
        try_files                   "" @404;
    
        # Проверяем правильность ссылки и md5
        if ($secure_link = "") { return 404; }
        
        # Используем соответсвующий фильтр
        image_filter                size;
    }

    # По аналогии остальные location для других фильтров
    location ~ ^/c/[^/]+/(d+|-)x(d+|-)/(.+) {
        set                         $width  $1;
        set                         $height $2;
        
        alias                       /www/myproject.ru/images/$3;
        try_files                   "" @404;
    
        if ($secure_link = "") { return 404; }
    
        image_filter                crop  $width  $height;
    }
    
    location ~ ^/r/[^/]+/(d+|-)x(d+|-)/(.+) {
        set                         $width  $1;
        set                         $height $2;

        alias                       /www/myproject.ru/images/$3;
        try_files                   "" @404;

        if ($secure_link = "") { return 404; }

        image_filter                resize  $width  $height;
    }

    location @404 { return 404; }
}


Yog li ntawd, cov duab ntxiv tuaj yeem tau txais los ntawm kev sib txuas hauv qab no:

• myproject.ru/preview/i[md5]/[path_to_image]
• myproject.ru/preview/c[md5]/[size]/[path_to_image]
• myproject.ru/preview/r[md5]/[size]/[path_to_image]

* try_files - rhiab rau qhov chaw thiab cov cim Lavxias, yog li kuv yuav tsum tau ua tus ntoo khaub lig nrog alias.

Siv hauv daim ntawv thov web

Ntawm qib kev thov web, koj tuaj yeem ua cov txheej txheem hauv qab no (Perl):

sub proxy_image {
    use Digest::MD5     qw /md5_hex/;
    my %params = @_;
    my $filter = {
                    size    => 'i',
                    resize  => 'r',
                    crop    => 'c'            
                  }->{$params{filter}} || 'r';
    my $path = ($filter ne 'i' ?
                    ( $params{height} || '_' ) . 'x' . ( $params{width} || '_' ) . '/' :
                    ()
               ) . $params{source};
    my $md5 = md5_hex( $path . 'secret' );
    $path = '/preview/' . $filter . '/' . $md5 . '/' . $path;
    return $path;
}

my $preview_path = &proxy_image(
                    source  => 'image1.jpg',
                    height  => 100,
                    width   => 100,
                    filter  => 'resize'
                );


Txawm hais tias kuv kuj xav kom suav qhov ntau thiab tsawg saib ua ntej.

Lub ncuav

Thaum rho tawm cov duab qub, saib ua ntej, ib txwm, yuav tsis raug tshem tawm ntawm lub cache kom txog thaum lub cache tsis raug cai, thiab hauv peb rooj plaub, kev saib ua ntej tuaj yeem muaj nyob rau ib hnub tom qab tshem tawm, tab sis qhov no yog lub sijhawm siab tshaj plaws.

tus thawj

Tau qhov twg los: www.hab.com