Name
    nginx_ajp_module - support AJP protocol proxy with Nginx

Synopsis
            http {
                    upstream tomcats {
                            server 127.0.0.1:8009;
                            keepalive 10;
                    }

                    server {

                            listen 80;

                            location / {
                                    ajp_keep_conn on;
                                    ajp_pass tomcats;
                            }
                    }
            }

Description
    With this module, Nginx can connect to AJP port directly. The motivation
    of writing these modules is Nginx's high performance and robustness.

Directives
  ajp_buffers
    syntax: *ajp_buffers the_number is_size;*

    default: *ajp_buffers 8 4k/8k;*

    context: *http, server, location*

    This directive specifies the number and the size of buffers, into which
    will be read the response, obtained from the AJP server. By default, the
    size of one buffer is equal to the size of a page. Depending on platform
    this is either 4K, 8K or 16K.

  ajp_buffer_size
    syntax: *ajp_buffer_size the_size;*

    default: *ajp_buffer_size 4k/8k;*

    context: *http, server, location*

    This directive sets the buffer size, into which will be read the first
    part of the response, obtained from the AJP server.

    In this part of response the small response-header is located, as a
    rule.

    By default, the buffersize is equal to the size of one buffer in
    directive "ajp_buffers"; however, it is possible to set it to less.

  ajp_cache
    syntax: *ajp_cache zone;*

    default: *off*

    context: *http, server, location*

    The directive specifies the area which actually is the share memory's
    name for caching. The same area can be used in several places. You must
    set the "ajp_cache_path" first.

  ajp_cache_key
    syntax: *ajp_cache_key line;*

    default: *none*

    context: *http, server, location*

    The directive specifies what information is included in the key for
    caching, for example

            ajp_cache_key "$host$request_uri$cookie_user";

    Note that by default, the hostname of the server is not included in the
    cache key. If you are using subdomains for different locations on your
    website, you need to include it, e.g. by changing the cache key to
    something like

            ajp_cache_key "$scheme$host$request_uri";

  ajp_cache_methods
    syntax: *ajp_cache_methods [GET HEAD POST];*

    default: *ajp_cache_methods GET HEAD;*

    context: *main,http,location*

    GET/HEAD is syntax sugar, i.e. you can not disable GET/HEAD even if you
    set just

            ajp_cache_methods  POST;

  ajp_cache_min_uses
    syntax: *ajp_cache_min_uses n;*

    default: *ajp_cache_min_uses 1;*

    context: *http, server, location*

    Sets the number of requests after which the response will be cached.

  ajp_cache_path
    syntax: *ajp_cache_path /path/to/cache [levels=m:n keys_zone=name:time
    inactive=time clean_time=time];*

    default: *none*

    context: *http, server, location*

    This directive sets the cache path and other cache parameters. Cached
    data stored in files. Key and filename in cache is md5 of proxied URL.
    Levels parameter set number of subdirectories in cache, for example for:

            ajp_cache_path  /data/nginx/cache  levels=1:2   keys_zone=one:10m;

    file names will be like:

    /data/nginx/cache/c/29/b7f54b2df7773722d382f4809d65029c

  ajp_cache_use_stale
    syntax: *ajp_cache_use_stale
    [updating|error|timeout|invalid_header|http_500];*

    default: *ajp_cache_use_stale off;*

    context: *http, server, location*

    If an error occurs while working with the AJP server it is possible to
    use a stale cached response. This directives determines in which cases
    it is permitted. The directive’s parameters match those of the
    "ajp_next_upstream" directive.

    Additionally, the updating parameter permits to use a stale cached
    response if it is currently being updated. This allows to minimize the
    number of accesses to AJP servers when updating cached data.

  ajp_cache_valid
    syntax: *ajp_cache_valid [http_error_code|time];*

    default: *none*

    context: *http, server, location*

    Sets caching time for different response codes. For example, the
    following directives

            ajp_cache_valid 200 302 10m;
            ajp_cache_valid 404      1m;

    set 10 minutes of caching for responses with codes 200 and 302, and 1
    minute for responses with code 404.

    If only caching time is specified

            ajp_cache_valid 5m;

    then only 200, 301, and 302 responses are cached.

    In addition, it can be specified to cache any responses using the any
    parameter:

            ajp_cache_valid 200 302 10m;
            ajp_cache_valid 301      1h;
            ajp_cache_valid any      1m;

    Parameters of caching can also be set directly in the response header.
    This has a higher precedence than setting of caching time using the
    directive. The “X-Accel-Expires” header field sets caching time of a
    response in seconds. The value 0 disables to cache a response. If a
    value starts with the prefix @, it sets an absolute time in seconds
    since Epoch, up to which the response may be cached. If header does not
    include the “X-Accel-Expires” field, parameters of caching may be
    set in the header fields “Expires” or “Cache-Control”. If a
    header includes the “Set-Cookie” field, such a response will not be
    cached. Processing of one or more of these response header fields can be
    disabled using the "ajp_ignore_headers" directive.

  ajp_connect_timeout
    syntax: *ajp_connect_timeout time;*

    default: *ajp_connect_timeout 60s;*

    context: *http, server, location*

    This directive assigns a timeout for the connection to the upstream
    server. It is necessary to keep in mind that this time out cannot be
    more than 75 seconds.

    This is not the time until the server returns the pages, this is the
    ajp_read_timeout statement. If your upstream server is up, but hanging
    (e.g. it does not have enough threads to process your request so it puts
    you in the pool of connections to deal with later), then this statement
    will not help as the connection to the server has been made.

  ajp_header_packet_buffer_size
    syntax: *ajp_header packet_buffer_size;*

    default: *ajp_header_packet_buffer_size 8k;*

    context: *http, server, location*

    Set the buffer size of Forward Request packet. The range is (0, 2^16).

  ajp_hide_header
    syntax: *ajp_hide_header name;*

    context: *http, server, location*

    By default, Nginx does not pass headers "Status" and "X-Accel-..." from
    the AJP process back to the client. This directive can be used to hide
    other headers as well.

    If the headers "Status" and "X-Accel-..." must be provided, then it is
    necessary to use directive ajp_pass_header to force them to be returned
    to the client.

  ajp_ignore_headers
    syntax: *ajp_ignore_headers name [name ...];*

    default: *none*

    context: *http, server, location*

    This directive(0.7.54+) prohibits the processing of the header lines
    from the proxy server's response.

    It can specify the string as "X-Accel-Redirect", "X-Accel-Expires",
    "Expires" or "Cache-Control".

  ajp_ignore_client_abort
    syntax: *ajp_ignore_client_abort on|off;*

    default: *ajp_ignore_client_abort off;*

    context: *http, server, location*

    This directive determines if current request to the AJP-server must be
    aborted in case the client aborts the request to the server.

  ajp_intercept_errors
    syntax: *ajp_intercept_errors on|off;*

    default: *ajp_intercept_errors off;*

    context: *http, server, location*

    This directive determines whether or not to transfer 4xx and 5xx errors
    back to the client or to allow Nginx to answer with directive
    error_page.

    Note: You need to explicitly define the error_page handler for this for
    it to be useful. As Igor says, "nginx does not intercept an error if
    there is no custom handler for it it does not show its default pages.
    This allows to intercept some errors, while passing others as are."

  ajp_keep_conn
    syntax: *ajp_keep_conn on|off;*

    default: *ajp_keep_conn off;*

    context: *http, server, location*

    This directive determines whether or not to keep the connection alive
    with backend server.

  ajp_next_upstream
    syntax: *ajp_next_upstream
    [error|timeout|invalid_header|http_500|http_502|http_503|http_504|http_4
    04|off];*

    default: *ajp_next_upstream error timeout;*

    context: *http, server, location*

    Directive determines, in what cases the request will be transmitted to
    the next server:

    error — an error has occurred while connecting to the server, sending
    a request to it, or reading its response;
    timeout — occurred timeout during the connection with the server,
    transfer the request or while reading response from the server;
    invalid_header — server returned a empty or incorrect answer;
    http_500 — server returned answer with code 500;
    http_502 — server returned answer with code 502;
    http_503 — server returned answer with code 503;
    http_504 — server returned answer with code 504;
    http_404 — server returned answer with code 404;
    off — it forbids the request transfer to the next server Transferring
    the request to the next server is only possible when nothing has been
    transferred to the client -- that is, if an error or timeout arises in
    the middle of the transfer of the request, then it is not possible to
    retry the current request on a different server.
  ajp_max_data_packet_size
    syntax: *ajp_max_data_packet_size size;*

    default: *ajp_max_data_packet_size 8k;*

    context: *http, server, location*

    Set the maximum size of AJP's Data packet. The range is [8k, 2^16];

  ajp_max_temp_file_size
    syntax: *ajp_max_temp_file_size size;*

    default: *ajp_max_temp_file_size 1G;*

    context: *http, server, location, if*

    The maximum size of a temporary file when the content is larger than the
    proxy buffer. If file is larger than this size, it will be served
    synchronously from upstream server rather than buffered to disk.

    If ajp_max_temp_file_size is equal to zero, temporary files usage will
    be disabled.

  ajp_pass
    syntax: *ajp_pass ajp-server*

    default: *none*

    context: *location, if in location*

    Directive assigns the port or socket on which the AJP-server is
    listening. Port can be indicated by itself or as an address and port,
    for example:

            ajp_pass   localhost:9000;

    using a Unix domain socket:

            ajp_pass   unix:/tmp/ajp.socket;

    You may also use an upstream block.

            upstream backend  {
                    server   localhost:1234;
            }

            ajp_pass   backend;

  ajp_pass_header
    syntax: *ajp_pass_header name;*

    context: *http, server, location*

    Permits to pass specific header fields from the AJP server to a client.

  ajp_pass_request_headers
    syntax: *ajp_pass_request_headers [ on | off ];*

    default: *ajp_pass_request_headers on;*

    context: *http, server, location*

    Permits to pass request header fields from the client to server.

  ajp_pass_request_body
    syntax: *ajp_pass_request_body [ on | off ] ;*

    default: *ajp_pass_request_body on;*

    context: *http, server, location*

    Permits to pass request body from the client to server.

  ajp_read_timeout
    syntax: *ajp_read_timeout time;*

    default: *ajp_read_timeout_time 60*

    context: *http, server, location*

    Directive sets the amount of time for upstream to wait for a AJP process
    to send data. Change this directive if you have long running AJP
    processes that do not produce output until they have finished
    processing. If you are seeing an upstream timed out error in the error
    log, then increase this parameter to something more appropriate.

  ajp_send_lowat
    syntax: *ajp_send_lowat [ on | off ];*

    default: *ajp_send_lowat off;*

    context: *http, server, location, if*

    This directive set SO_SNDLOWAT. This directive is only available on
    FreeBSD

  ajp_send_timeout
    syntax: *ajp_send_timeout time;*

    default: *ajp_send_timeout 60;*

    context: *http, server, location*

    This directive assigns timeout with the transfer of request to the
    upstream server. Timeout is established not on entire transfer of
    request, but only between two write operations. If after this time the
    upstream server will not take new data, then nginx is shutdown the
    connection.

  ajp_store
    syntax: *ajp_store [on | off | path] ;*

    default: *ajp_store off;*

    context: *http, server, location*

    This directive sets the path in which upstream files are stored. The
    parameter "on" preserves files in accordance with path specified in
    directives *alias* or *root*. The parameter "off" forbids storing.
    Furthermore, the name of the path can be clearly assigned with the aid
    of the line with the variables:

            ajp_store   /data/www$original_uri;

    The time of modification for the file will be set to the date of
    "Last-Modified" header in the response. To be able to safe files in this
    directory it is necessary that the path is under the directory with
    temporary files, given by directive "ajp_temp_path" for the data
    location.

    This directive can be used for creating the local copies for dynamic
    output of the backend which is not very often changed, for example:

            location /images/ {
                    root                 /data/www;
                    error_page           404 = @fetch;
            }

            location @fetch {
                    internal;
                    ajp_pass           backend;
                    ajp_store          on;
                    ajp_store_access   user:rw  group:rw  all:r;
                    ajp_temp_path      /data/temp;

                    root               /data/www;
            }

    To be clear ajp_store is not a cache, it's rather mirror on demand.

  ajp_store_access
    syntax: *ajp_store_access users:permissions [users:permission ...];*

    default: *ajp_store_access user:rw;*

    context: *http, server, location*

    This directive assigns the permissions for the created files and
    directories, for example:

            ajp_store_access  user:rw  group:rw  all:r;

    If any rights for groups or all are assigned, then it is not necessary
    to assign rights for user:

            ajp_store_access  group:rw  all:r;

  ajp_temp_path
    syntax: *ajp_temp_path dir-path [ level1 [ level2 [ level3 ] ] ] ;*

    default: *$NGX_PREFIX/ajp_temp*

    context: *http, server, location*

    This directive works like client_body_temp_path to specify a location to
    buffer large proxied requests to the filesystem.

  ajp_temp_file_write_size
    syntax: *ajp_temp_file_write_size size;*

    default: *ajp_temp_file_write_size ["#ajp buffer size"] * 2;*

    context: *http, server, location, if*

    Sets the amount of data that will be flushed to the ajp_temp_path when
    writing. It may be used to prevent a worker process blocking for too
    long while spooling data.

Installation
    Download the latest version of the release tarball of this module from
    github (<http://github.com/yaoweibin/nginx_ajp_module>)

    Grab the nginx source code from nginx.org (<http://nginx.org/>), for
    example, the version 1.2.0 (see nginx compatibility), and then build the
    source with this module:

        $ wget 'http://nginx.org/download/nginx-1.4.4.tar.gz'
        $ tar -xzvf nginx-1.4.4.tar.gz
        $ cd nginx-1.4.4/
        $ ./configure --add-module=/path/to/nginx_ajp_module

        $ make
        $ make install

Compatibility
    The master branch is for Nginx-1.1.4+
    If you want to use it with Nginx-1.0.x, you can use this nginx-1.0
    (<https://github.com/yaoweibin/nginx_ajp_module/tree/nginx-1.0>) branch.
TODO
    SSL
Known Issues
    *

Changelogs
  v0.3
    remove the jvm_route and keepalive module
  v0.2
    bugfix
  v0.1
    first release
Authors
    Weibin Yao(姚伟斌) *yaoweibin AT gmail DOT com*
    Jinti Shen(路奇) *jinti.shen AT gmail DOT com*
    Joshua Zhu(叔度) *zhuzhaoyuan AT gmail DOT com*
    Simon Liu(雕梁) *simohayha.bobo AT gmail DOT com*
    Matthew Ma(东坡) *mj19821214 AT gmail DOT com*
Acknowledgments
    Thanks 李金虎(beagem@163.com) to improve the keepalive feature with
    this module.
License
    This README template is from agentzh (<http://github.com/agentzh>).

    I borrowed a lot of codes from Fastcgi module of Nginx. This part of
    code is copyrighted by Igor Sysoev. And the design of apache's
    mod_ajp_proxy
    (<http://httpd.apache.org/docs/trunk/mod/mod_proxy_ajp.html>). Thanks
    for their hard work.

    This module is licensed under the BSD license.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:

    Redistributions of source code must retain the above copyright notice,
    this list of conditions and the following disclaimer.
    Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
    IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
    TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
    PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
    TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

