http_proxy module

Contents

http_proxy module#

Allows passing requests to another (proxied) server.

Example Configuration#

location / {
    proxy_pass       http://localhost:8000;
    proxy_set_header Host      $host;
    proxy_set_header X-Real-IP $remote_addr;
}

Directives#

proxy_bind#

Syntax:

proxy_bind address [transparent] | off;

Default:

Context:

http, server, location

Makes outgoing connections to a proxied server originate from the specified local IP address with an optional port. Parameter value can contain variables. The special value off cancels the effect of the proxy_bind directive inherited from the previous configuration level, which allows the system to auto-assign the local IP address and port.

The transparent parameter allows outgoing connections to a proxied server originate from a non-local IP address, for example, from a real IP address of a client:

proxy_bind $remote_addr transparent;

In order for this parameter to work, it is usually necessary to run Angie worker processes with the superuser privileges. On Linux it is not required as if the transparent parameter is specified, worker processes inherit the CAP_NET_RAW capability from the master process.

Important

It is necessary to configure kernel routing table to intercept network traffic from the proxied server.

proxy_buffer_size#

Syntax:

proxy_buffer_size size;

Default:

proxy_buffer_size 4k|8k;

Context:

http, server, location

Sets the size of the buffer used for reading the first part of the response received from the proxied server. This part usually contains a small response header. By default, the buffer size is equal to one memory page. This is either 4K or 8K, depending on a platform. It can be made smaller, however.

proxy_buffering#

Syntax:

proxy_buffering size;

Default:

proxy_buffering on;

Context:

http, server, location

Enables or disables buffering of responses from the proxied server.

on

Angie receives a response from the proxied server as soon as possible, saving it into the buffers set by the proxy_buffer_size and proxy_buffers directives. If the whole response does not fit into memory, a part of it can be saved to a temporary file on the disk. Writing to temporary files is controlled by the proxy_max_temp_file_size and proxy_temp_file_write_size directives.

off

he response is passed to a client synchronously, immediately as it is received. Angie will not try to read the whole response from the proxied server. The maximum size of the data that Angie can receive from the server at a time is set by the proxy_buffer_size directive.

Buffering can also be enabled or disabled by passing “yes” or “no” in the “X-Accel-Buffering” response header field. This capability can be disabled using the proxy_ignore_headers directive.

proxy_buffers#

Syntax:

proxy_buffers number size;

Default:

proxy_buffers 8 4k|8k;

Context:

http, server, location

Sets the number and size of the buffers used for reading a response from the proxied server, for a single connection.
By default, the buffer size is equal to one memory page. This is either 4K or 8K, depending on a platform.

proxy_busy_buffers_size#

Syntax:

proxy_busy_buffers_size size;

Default:

proxy_buffers 8k|16k;

Context:

http, server, location

When buffering of responses from the proxied server is enabled, limits the total size of buffers that can be busy sending a response to the client while the response is not yet fully read. In the meantime, the rest of the buffers can be used for reading the response and, if needed, buffering part of the response to a temporary file.
By default, size is limited by the size of two buffers set by the proxy_buffer_size and proxy_buffers directives.

proxy_cache#

Syntax:

proxy_cache zone | off;

Default:

proxy_cache off;

Context:

http, server, location

Defines a shared memory zone for caching. A zone can be used in the configuration multiple times. The parameter’s value allows variables.

off

disables caching inherited from the previous configuration level.

proxy_cache_background_update#

Syntax:

proxy_cache_background_update on | off;

Default:

proxy_cache_background_update off;

Context:

http, server, location

Allows starting a background subrequest to update an expired cache item, while a stale cached response is returned to the client.

Attention

Note that it is necessary to allow the usage of a stale cached response when it is being updated.

proxy_cache_bypass#

Syntax:

proxy_cache_bypass …;

Default:

Context:

http, server, location

Defines conditions under which the response will not be taken from a cache. If at least one value of the string parameters is not empty and is not equal to “0” then the response will not be taken from the cache:

proxy_cache_bypass $cookie_nocache $arg_nocache$arg_comment;
proxy_cache_bypass $http_pragma    $http_authorization;

Can be used along with the proxy_no_cache directive.

proxy_cache_convert_head#

Syntax:

proxy_cache_convert_head on | off;

Default:

proxy_cache_convert_head on;

Context:

http, server, location

Enables or disables the conversion of the “HEAD” method to “GET” for caching. When the conversion is disabled, the cache key should be configured to include the $request_method.

proxy_cache_key#

Syntax:

proxy_cache_key string;

Default:

proxy_cache_key $scheme$proxy_host$request_uri;

Context:

http, server, location

Defines a key for caching, for example

proxy_cache_key "$host$request_uri $cookie_user";

By default, the directive’s value is close to the string

proxy_cache_key $scheme$proxy_host$uri$is_args$args;

proxy_cache_lock#

Syntax:

proxy_cache_lock on | off;

Default:

proxy_cache_lock off;

Context:

http, server, location

When enabled, only one request at a time will be allowed to populate a new cache element identified according to the proxy_cache_key directive by passing a request to a proxied server. Other requests of the same cache element will either wait for a response to appear in the cache or the cache lock for this element to be released, up to the time set by the proxy_cache_lock_timeout directive.

proxy_cache_lock_age#

Syntax:

proxy_cache_lock_age time;

Default:

proxy_cache_lock_age 5s;

Context:

http, server, location

If the last request passed to the proxied server for populating a new cache element has not completed for the specified time, one more request may be passed to the proxied server.

proxy_cache_lock_timeout#

Syntax:

proxy_cache_lock_timeout time;

Default:

proxy_cache_lock_timeout 5s;

Context:

http, server, location

Sets a timeout for proxy_cache_lock. When the time expires, the request will be passed to the proxied server, however, the response will not be cached.

proxy_cache_max_range_offset#

Syntax:

proxy_cache_max_range_offset number;

Default:

Context:

http, server, location

Sets an offset in bytes for byte-range requests. If the range is beyond the offset, the range request will be passed to the proxied server and the response will not be cached.

proxy_cache_methods#

Syntax:

proxy_cache_methods GET | HEAD | POST …;

Default:

proxy_cache_methods GET HEAD;

Context:

http, server, location

If the client request method is listed in this directive then the response will be cached. “GET” and “HEAD” methods are always added to the list, though it is recommended to specify them explicitly. See also the proxy_no_cache directive.

proxy_cache_min_uses#

Syntax:

proxy_cache_min_uses number;

Default:

proxy_cache_min_uses 1;

Context:

http, server, location

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

proxy_cache_path#

Syntax:

proxy_cache_path path [levels=levels] [use_temp_path=on|off] keys_zone=name:size [inactive=time] [max_size=size] [min_free=size] [manager_files=number] [manager_sleep=time] [manager_threshold=time] [loader_files=number] [loader_sleep=time] [loader_threshold=time];

Default:

Context:

http

Sets the path and other parameters of a cache. Cache data are stored in files. The file name in a cache is a result of applying the MD5 function to the cache key.

levels

defines hierarchy levels of a cache: from 1 to 3, each level accepts values 1 or 2.

For example, in the following configuration:

proxy_cache_path /data/angie/cache levels=1:2 keys_zone=one:10m;

file names in a cache will look like this:

/data/angie/cache/c/29/b7f54b2df7773722d382f4809d65029c

A cached response is first written to a temporary file, and then the file is renamed. Temporary files and the cache can be put on different file systems. However, be aware that in this case a file is copied across two file systems instead of the cheap renaming operation. It is thus recommended that for any given location both cache and a directory holding temporary files are put on the same file system.

use_temp_path=on | off

Sets the directory for temporary files

    on

If this parameter is omitted or set to the value on, the directory set by the proxy_temp_path directive for the given location will be used.

    off

Temporary files will be put directly in the cache directory.

keys_zone

Configures the name and size for a shared memory zone to store all active keys and information about data.
One megabyte zone can store about 8 thousand keys.

inactive

Cached data that are not accessed during the time specified by this parameter get removed from the cache regardless of their freshness.
By default, is set to 10 minutes.

The special cache manager process monitors the maximum cache size and the minimum amount of free space on the file system with cache and when the size is exceeded or there is not enough free space, it removes the least recently used data. The data is removed in iterations.

max_size

maximum cache size

min_free

minimum amount of free space on the file system with cache

manager_files

limits the number of items to be deleted during one iteration
by default 100

manager_threshold

limits the duration of one iteration
by default, 200 milliseconds

manager_sleep

configures a pause between interactions
by default, 50 milliseconds

A minute after the Angie starts the special cache loader process is activated. It loads information about previously cached data stored on file system into a cache zone. The loading is also done in iterations.

loader_files

limits the number of items to load during one iteration
by default, 100

loader_threshold

limits the duration of one iteration
by default, 200 milliseconds

loader_sleep

configures a pause between interactions
by default, 50 milliseconds

proxy_cache_revalidate#

Syntax:

proxy_cache_revalidate on | off;

Default:

proxy_cache_revalidate off;

Context:

http, server, location

Enables revalidation of expired cache items using conditional requests with the “If-Modified-Since” and “If-None-Match” header fields.

proxy_cache_use_stale#

Syntax:

proxy_cache_use_stale error | timeout | invalid_header | updating | http_500 | http_502 | http_503 | http_504 | http_403 | http_404 | http_429 | off …;

Default:

proxy_cache_use_stale off;

Context:

http, server, location

Determines in which cases a stale cached response can be used during communication with the proxied server. The directive’s parameters match the parameters of the proxy_next_upstream directive.

error

permits using a stale cached response if a proxied server to process a request cannot be selected.

updating

additional parameter, permits using a stale cached response if it is currently being updated. This allows minimizing the number of accesses to proxied servers when updating cached data.

Using a stale cached response can also be enabled directly in the response header for a specified number of seconds after the response became stale:

  • The stale-while-revalidate extension of the “Cache-Control” header field permits using a stale cached response if it is currently being updated.

  • The stale-if-error extension of the “Cache-Control” header field permits using a stale cached response in case of an error.

Note

This has lower priority than using the directive parameters.

To minimize the number of accesses to proxied servers when populating a new cache element, the proxy_cache_lock directive can be used.

proxy_cache_valid#

Syntax:

proxy_cache_valid [code …] time;

Default:

Context:

http, server, location

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

proxy_cache_valid 200 302 10m;
proxy_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

proxy_cache_valid 5m;

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

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

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

Note

Parameters of caching can also be set directly in the response header. This has higher priority than setting of caching time using the directive

  • The “X-Accel-Expires” header field sets caching time of a response in seconds. The zero value disables caching for a response. If the value starts with the @ prefix, it sets an absolute time in seconds since Epoch, up to which the response may be cached.

  • If the header does not include the “X-Accel-Expires” field, parameters of caching may be set in the header fields “Expires” or “Cache-Control”.

  • If the header includes the “Set-Cookie” field, such a response will not be cached.

  • If the header includes the “Vary” field with the special value “*”, such a response will not be cached. If the header includes the “Vary” field with another value, such a response will be cached taking into account the corresponding request header fields.

Processing of one or more of these response header fields can be disabled using the proxy_ignore_headers directive.

proxy_connect_timeout#

Syntax:

proxy_connect_timeout time;

Default:

proxy_connect_timeout 60s;

Context:

http, server, location

Defines a timeout for establishing a connection with a proxied server. It should be noted that this timeout cannot usually exceed 75 seconds.

proxy_force_ranges#

Syntax:

proxy_force_ranges off;

Default:

proxy_force_ranges off;

Context:

http, server, location

Enables byte-range support for both cached and uncached responses from the proxied server regardless of the “Accept-Ranges” field in these responses.

proxy_headers_hash_bucket_size#

Syntax:

proxy_headers_hash_bucket_size size;

Default:

proxy_headers_hash_bucket_size 64;

Context:

http, server, location

Sets the bucket size for hash tables used by the proxy_hide_header and proxy_set_header directives. The details of setting up hash tables are provided separately.

proxy_headers_hash_max_size#

Syntax:

proxy_headers_hash_max_size size;

Default:

proxy_headers_hash_max_size 512;

Context:

http, server, location

Sets the maximum size of hash tables used by the proxy_hide_header and proxy_set_header directives. The details of setting up hash tables are provided separately.

proxy_hide_header#

Syntax:

proxy_hide_header field;

Default:

Context:

http, server, location

By default, Angie does not pass the header fields “Date”, “Server”, “X-Pad”, and “X-Accel-…” from the response of a proxied server to a client. The proxy_hide_header directive sets additional fields that will not be passed. If, on the contrary, the passing of fields needs to be permitted, the proxy_pass_header directive can be used.

proxy_http_version#

Syntax:

proxy_http_version 1.0 | 1.1 | 3;

Default:

proxy_http_version 1.0;

Context:

http, server, location, if in location, limit_except

Sets the HTTP protocol version for proxying. By default, version 1.0 is used. Version 1.1 or higher is recommended for use with keepalive connections.

proxy_http3_hq#

Syntax:

proxy_http3_hq on | off;

Default:

proxy_http3_hq off;

Context:

http, server

Toggles the special hq-interop negotiation mode, which is used for QUIC interop tests that Angie relies on.

proxy_http3_max_concurrent_streams#

Syntax:

proxy_http3_max_concurrent_streams number;

Default:

proxy_http3_max_concurrent_streams 128;

Context:

http, server

Sets the maximum number of concurrent HTTP/3 request streams in a connection. Requires enabling :ref:keepalive connections <u_keepalive>`.

proxy_http3_stream_buffer_size#

Syntax:

proxy_http3_stream_buffer_size size;

Default:

proxy_http3_stream_buffer_size 64k;

Context:

http, server

Sets the size of the read-write buffer used with QUIC streams.

proxy_ignore_client_abort#

Syntax:

proxy_ignore_client_abort on | off;

Default:

proxy_ignore_client_abort off;

Context:

http, server, location

Determines whether the connection with a proxied server should be closed when a client closes the connection without waiting for a response.

proxy_ignore_headers#

Syntax:

proxy_ignore_headers field …;

Default:

Context:

http, server, location

Disables processing of certain response header fields from the proxied server. The following fields can be ignored: “X-Accel-Redirect”, “X-Accel-Expires”, “X-Accel-Limit-Rate”, “X-Accel-Buffering”, “X-Accel-Charset”, “Expires”, “Cache-Control”, “Set-Cookie”, and “Vary”.

If not disabled, processing of these header fields has the following effect:

  • “X-Accel-Expires”, “Expires”, “Cache-Control”, “Set-Cookie” and “Vary” set the parameters of response caching;

  • “X-Accel-Redirect” performs an internal redirect to the specified URI;

  • “X-Accel-Limit-Rate” sets the rate limit for transmission of a response to a client;

  • “X-Accel-Buffering” enables or disables buffering of a response;

  • “X-Accel-Charset” sets the desired charset of a response.

proxy_intercept_errors#

Syntax:

proxy_intercept_errors on | off;

Default:

proxy_intercept_errors off;

Context:

http, server, location

Determines whether proxied responses with codes greater than or equal to 300 should be passed to a client or be intercepted and redirected to Angie for processing with the error_page directive.

proxy_limit_rate#

Syntax:

proxy_limit_rate rate;

Default:

proxy_limit_rate 0;

Context:

http, server, location

Limits the speed of reading the response from the proxied server. The rate is specified in bytes per second.

0

disables rate limiting

Note

The limit is set per a request, and so if Angie simultaneously opens two connections to the proxied server, the overall rate will be twice as much as the specified limit. The limitation works only if buffering of responses from the proxied server is enabled.

proxy_max_temp_file_size#

Syntax:

proxy_max_temp_file_size size;

Default:

proxy_max_temp_file_size 1024m;

Context:

http, server, location

When buffering of responses from the proxied server is enabled, and the whole response does not fit into the buffers set by the proxy_buffer_size and proxy_buffers directives, a part of the response can be saved to a temporary file. This directive sets the maximum size of the temporary file. The size of data written to the temporary file at a time is set by the proxy_temp_file_write_size directive.

0

disables buffering of responses to temporary files

Note

This restriction does not apply to responses that will be cached or stored on disk.

proxy_method#

Syntax:

proxy_method method;

Default:

Context:

http, server, location

Specifies the HTTP method to use in requests forwarded to the proxied server instead of the method from the client request. Parameter value can contain variables.

proxy_next_upstream#

Syntax:

proxy_next_upstream error | timeout | invalid_header | http_500 | http_502 | http_503 | http_504 | http_403 | http_404 | http_429 | non_idempotent | off …;

Default:

proxy_next_upstream error timeout;

Context:

http, server, location

Specifies in which cases a request should be passed to the next server in the upstream pool:

error

an error occurred while establishing a connection with the server, passing a request to it, or reading the response header;

timeout

a timeout has occurred while establishing a connection with the server, passing a request to it, or reading the response header;

invalid_header

a server returned an empty or invalid response;

http_500

a server returned a response with the code 500;

http_502

a server returned a response with the code 502;

http_503

a server returned a response with the code 503;

http_504

a server returned a response with the code 504;

http_403

a server returned a response with the code 403;

http_404

a server returned a response with the code 404;

http_429

a server returned a response with the code 429;

non_idempotent

normally, requests with a non-idempotent method (POST, LOCK, PATCH) are not passed to the next server if a request has been sent to an upstream server; enabling this option explicitly allows retrying such requests;

off

disables passing a request to the next server.

Note

One should bear in mind that passing a request to the next server is only possible if nothing has been sent to a client yet. That is, if an error or timeout occurs in the middle of the transferring of a response, fixing this is impossible.

The directive also defines what is considered an unsuccessful attempt of communication with a server.

error
timeout
invalid_header

always considered unsuccessful attempts, even if they are not specified in the directive

http_500
http_502
http_503
http_504
http_429

considered unsuccessful attempts only if they are specified in the directive

http_403
http_404

never considered unsuccessful attempts

Passing a request to the next server can be limited by the number of tries and by time.

proxy_next_upstream_timeout#

Syntax:

proxy_next_upstream_timeout time;

Default:

proxy_next_upstream_timeout 0;

Context:

http, server, location

Limits the time during which a request can be passed to the next server.

0

turns off this limitation

proxy_next_upstream_tries#

Syntax:

proxy_next_upstream_tries number;

Default:

proxy_next_upstream_tries 0;

Context:

http, server, location

Limits the number of possible tries for passing a request to the next server.

0

turns off this limitation

proxy_no_cache#

Syntax:

proxy_no_cache string …;

Default:

Context:

http, server, location

Defines conditions under which the response will not be saved to a cache. If at least one value of the string parameters is not empty and is not equal to “0” then the response will not be saved:

proxy_no_cache $cookie_nocache $arg_nocache$arg_comment;
proxy_no_cache $http_pragma    $http_authorization;

Can be used along with the proxy_cache_bypass directive.

proxy_pass#

Syntax:

proxy_pass URL;

Default:

Context:

location, if in location

Sets the protocol and address of a proxied server and an optional URI to which a location should be mapped. As a protocol, http or https can be specified. The address can be specified as a domain name or IP address, and an optional port:

proxy_pass http://localhost:8000/uri/;

or as a UNIX domain socket path specified after the word unix and enclosed in colons:

proxy_pass http://unix:/tmp/backend.socket:/uri/;

If a domain name resolves to several addresses, all of them will be used in a round-robin fashion. In addition, an address can be specified as a server group.

Parameter value can contain variables. In this case, if an address is specified as a domain name, the name is searched among the described server groups, and, if not found, is determined using a resolver.

A request URI is passed to the server as follows:

  • If the proxy_pass directive is specified with a URI, then when a request is passed to the server, the part of a normalized request URI matching the location is replaced by a URI specified in the directive:

location /name/ {
    proxy_pass http://127.0.0.1/remote/;
}
  • If proxy_pass is specified without a URI, the request URI is passed to the server in the same form as sent by a client when the original request is processed, or the full normalized request URI is passed when processing the changed URI:

location /some/path/ {
    proxy_pass http://127.0.0.1;
}

In some cases, the part of a request URI to be replaced cannot be determined:

  • When location is specified using a regular expression, and also inside named locations

In these cases, proxy_pass should be specified without a URI.

  • When the URI is changed inside a proxied location using the rewrite directive, and this same configuration will be used to process a request (break):

location /name/ {
    rewrite    /name/([^/]+) /users?name=$1 break;
    proxy_pass http://127.0.0.1;
}

In this case, the URI specified in the directive is ignored and the full changed request URI is passed to the server.

  • When variables are used in proxy_pass:

location /name/ {
    proxy_pass http://127.0.0.1$request_uri;
}

In this case, if URI is specified in the directive, it is passed to the server as is, replacing the original request URI.

WebSocket proxying requires special configuration.

proxy_pass_header#

Syntax:

proxy_pass_header field …;

Default:

Context:

http, server, location

Permits passing otherwise disabled header fields from a proxied server to a client.

proxy_pass_request_body#

Syntax:

proxy_pass_request_body on | off;

Default:

proxy_pass_request_body on;

Context:

http, server, location

Indicates whether the original request body is passed to the proxied server.

location /x-accel-redirect-here/ {
    proxy_method GET;
    proxy_pass_request_body off;
    proxy_set_header Content-Length "";

    proxy_pass ...;
}

See also the proxy_set_header and proxy_pass_request_headers directives.

proxy_pass_request_headers#

Syntax:

proxy_pass_request_headers on | off;

Default:

proxy_pass_request_headers on;

Context:

http, server, location

Indicates whether the header fields of the original request are passed to the proxied server.

location /x-accel-redirect-here/ {
    proxy_method GET;
    proxy_pass_request_headers off;
    proxy_pass_request_body off;

    proxy_pass ...;
}

See also the proxy_set_header and proxy_pass_request_body directives.

proxy_quic_active_connection_id_limit#

Syntax:

proxy_quic_active_connection_id_limit number;

Default:

proxy_quic_active_connection_id_limit 2;

Context:

http, server

Sets the QUIC active_connection_id_limit transport parameter value. This is the maximum number of active connection IDs that can be maintained per server.

proxy_quic_gso#

Syntax:

proxy_quic_gso on | off;

Default:

proxy_quic_gso off;

Context:

http, server

Toggles sending data in QUIC-optimized batch mode using (generic segmentation offload).

proxy_quic_host_key#

Syntax:

proxy_quic_host_key file;

Default:

Context:

http, server

Sets a file with the secret key used with QUIC to encrypt Stateless Reset and Address Validation tokens. By default, a random key is generated at each restart. Tokens generated with old keys are not accepted.

proxy_read_timeout#

Syntax:

proxy_read_timeout time;

Default:

proxy_read_timeout 60s;

Context:

http, server, location

Defines a timeout for reading a response from the proxied server. The timeout is set only between two successive read operations, not for the transmission of the whole response. If the proxied server does not transmit anything within this time, the connection is closed.

proxy_redirect#

Syntax:

proxy_redirect default;
proxy_redirect off;
proxy_redirect redirect replacement;

Default:

proxy_redirect default;

Context:

http, server, location

Sets the text that should be changed in the “Location” and “Refresh” header fields of a proxied server response.

Suppose a proxied server returned the header field:

Location: http://localhost:8000/two/some/uri/

The directive

proxy_redirect http://localhost:8000/two/ http://frontend/one/;

will rewrite this string to:

Location: http://frontend/one/some/uri/

A server name may be omitted in the replacement string:

proxy_redirect http://localhost:8000/two/ /;

then the primary server’s name and port, if different from 80, will be inserted.

The default replacement specified by the default parameter uses the parameters of the location and proxy_pass directives. Hence, the two configurations below are equivalent:

location /one/ {
    proxy_pass     http://upstream:port/two/;
    proxy_redirect default;
location /one/ {
    proxy_pass     http://upstream:port/two/;
    proxy_redirect http://upstream:port/two/ /one/;

Caution

The default parameter is not permitted if proxy_pass is specified using variables.

A replacement string can contain variables:

proxy_redirect http://localhost:8000/ http://$host:$server_port/;

A redirect can also contain variables:

proxy_redirect http://$proxy_host:8000/ /;

The directive can be specified using regular expressions. In this case, redirect should either start with the “~” symbol for a case-sensitive matching, or with the “~*” symbols for case-insensitive matching. The regular expression can contain named and positional captures, and replacement can reference them:

proxy_redirect ~^(http://[^:]+):\d+(/.+)$ $1$2;
proxy_redirect ~*/user/([^/]+)/(.+)$      http://$1.example.com/$2;

Several proxy_redirect directives can be specified on the same level:

proxy_redirect default;
proxy_redirect http://localhost:8000/  /;
proxy_redirect http://www.example.com/ /;

If several directives can be applied to the header fields of a proxied server response, the first matching directive will be chosen.

The off parameter cancels the effect of the proxy_redirect directives inherited from the previous configuration level.

Using this directive, it is also possible to add host names to relative redirects issued by a proxied server:

proxy_redirect / /;

proxy_request_buffering#

Syntax:

proxy_request_buffering on | off;

Default:

proxy_request_buffering on;

Context:

http, server, location

Enables or disables buffering of a client request body.

on

the entire request body is read from the client before sending the request to a proxied server.

off

the request body is sent to the proxied server immediately as it is received. In this case, the request cannot be passed to the next server if Angie already started sending the request body.

When HTTP/1.1 chunked transfer encoding is used to send the original request body, the request body will be buffered regardless of the directive value unless HTTP/1.1 is enabled for proxying.

proxy_send_lowat#

Syntax:

proxy_send_lowat size;

Default:

proxy_send_lowat 0;

Context:

http, server, location

If the directive is set to a non-zero value, Angie will try to minimize the number of send operations on outgoing connections to a proxied server by using either NOTE_LOWAT flag of the kqueue method, or the SO_SNDLOWAT socket option, with the specified size.

Note

This directive is ignored on Linux, Solaris, and Windows.

proxy_send_timeout#

Syntax:

proxy_send_timeout time;

Default:

proxy_send_timeout 60s;

Context:

http, server, location

Sets a timeout for transmitting a request to the proxied server. The timeout is set only between two successive write operations, not for the transmission of the whole request. If the proxied server does not receive anything within this time, the connection is closed.

proxy_set_body#

Syntax:

proxy_set_body value;

Default:

Context:

http, server, location

Allows redefining the request body passed to the proxied server. The value can contain text, variables, and their combination.

proxy_set_header#

Syntax:

proxy_set_header field value;

Default:

proxy_set_header Host $proxy_host;

Context:

http, server, location

Allows redefining or appending fields to the request header passed to the proxied server. The value can contain text, variables, and their combinations. These directives are inherited from the previous configuration level if and only if there are no proxy_set_header directives defined on the current level. By default, only two fields are redefined:

proxy_set_header Host       $proxy_host;
proxy_set_header Connection close;

If caching is enabled, the header fields “If-Modified-Since”, “If-Unmodified-Since”, “If-None-Match”, “If-Match”, “Range”, and “If-Range” from the original request are not passed to the proxied server.

An unchanged “Host” request header field can be passed like this:

proxy_set_header Host       $http_host;

However, if this field is not present in a client request header then nothing will be passed. In such a case it is better to use the $host variable - its value equals the server name in the “Host” request header field or the primary server name if this field is not present:

proxy_set_header Host       $host;

In addition, the server name can be passed together with the port of the proxied server:

proxy_set_header Host       $host:$proxy_port;

If the value of a header field is an empty string then this field will not be passed to a proxied server:

proxy_set_header Accept-Encoding "";

proxy_socket_keepalive#

Syntax:

proxy_socket_keepalive on | off;

Default:

proxy_socket_keepalive off;

Context:

http, server, location

Configures the “TCP keepalive” behavior for outgoing connections to a proxied server.

""

By default, the operating system’s settings are in effect for the socket.

on

The SO_KEEPALIVE socket option is turned on for the socket.

proxy_ssl_certificate#

Syntax:

proxy_ssl_certificate file [file];

Default:

Context:

http, server, location

Specifies a file with the certificate in the PEM format used for authentication to a proxied HTTPS server. Variables can be used in the file name.

New in version 1.2.0.

When proxy_ssl_ntls enabled, directive accepts two arguments instead of one, sign and encryption parts of certificate:

location /proxy {
    proxy_ssl_ntls  on;

    proxy_ssl_certificate      sign.crt enc.crt;
    proxy_ssl_certificate_key  sign.key enc.key;

    proxy_ssl_ciphers "ECC-SM2-WITH-SM4-SM3:ECDHE-SM2-WITH-SM4-SM3:RSA";

    proxy_pass https://backend:443;
}

proxy_ssl_certificate_key#

Syntax:

proxy_ssl_certificate_key file [file];

Default:

Context:

http, server, location

Specifies a file with the secret key in the PEM format used for authentication to a proxied HTTPS server.

The value “engine:name:id” can be specified instead of the file, which loads a secret key with a specified id from the OpenSSL engine name. Variables can be used in the file name.

New in version 1.2.0.

When proxy_ssl_ntls enabled, directive accepts two arguments instead of one: sign and encryption parts of key:

location /proxy {
    proxy_ssl_ntls  on;

    proxy_ssl_certificate      sign.crt enc.crt;
    proxy_ssl_certificate_key  sign.key enc.key;

    proxy_ssl_ciphers "ECC-SM2-WITH-SM4-SM3:ECDHE-SM2-WITH-SM4-SM3:RSA";

    proxy_pass https://backend:443;
}

proxy_ssl_ciphers#

Syntax:

proxy_ssl_ciphers ciphers;

Default:

proxy_ssl_ciphers DEFAULT;

Context:

http, server, location

Specifies the enabled ciphers for requests to a proxied HTTPS server. The ciphers are specified in the format understood by the OpenSSL library.

The full list can be viewed using the “openssl ciphers” command.

proxy_ssl_conf_command#

Syntax:

proxy_ssl_conf_command name value;

Default:

Context:

http, server, location

Sets arbitrary OpenSSL configuration commands when establishing a connection with the proxied HTTPS server.

Important

The directive is supported when using OpenSSL 1.0.2 or higher.

Several proxy_ssl_conf_command directives can be specified on the same level. These directives are inherited from the previous configuration level if and only if there are no proxy_ssl_conf_command directives defined on the current level.

Caution

Note that configuring OpenSSL directly might result in unexpected behavior.

proxy_ssl_crl#

Syntax:

proxy_ssl_crl file;

Default:

Context:

http, server, location

Specifies a file with revoked certificates (CRL) in the PEM format used to verify the certificate of the proxied HTTPS server.

proxy_ssl_name#

Syntax:

proxy_ssl_name name;

Default:

proxy_ssl_name $proxy_host;

Context:

http, server, location

Allows overriding the server name used to verify the certificate of the proxied HTTPS server and to be passed through SNI when establishing a connection with the proxied HTTPS server.

By default, the host part of the proxy_pass URL is used.

proxy_ssl_ntls#

New in version 1.2.0.

Syntax:

proxy_ssl_ntls on | off;

Default:

proxy_ssl_ntls off;

Context:

http, server

Enables client-side support for NTLS using TongSuo library.

location /proxy {
    proxy_ssl_ntls  on;

    proxy_ssl_certificate      sign.crt enc.crt;
    proxy_ssl_certificate_key  sign.key enc.key;

    proxy_ssl_ciphers "ECC-SM2-WITH-SM4-SM3:ECDHE-SM2-WITH-SM4-SM3:RSA";

    proxy_pass https://backend:443;
}

Important

Build Angie using the –with-ntls configure option and link with NTLS-enabled SSL library

./configure --with-openssl=../Tongsuo-8.3.0 \
            --with-openssl-opt=enable-ntls  \
            --with-ntls

proxy_ssl_password_file#

Syntax:

proxy_ssl_password_file file;

Default:

Context:

http, server, location

Specifies a file with passphrases for secret keys where each passphrase is specified on a separate line. Passphrases are tried in turn when loading the key.

proxy_ssl_protocols#

Syntax:

proxy_ssl_protocols [SSLv2] [SSLv3] [TLSv1] [TLSv1.1] [TLSv1.2] [TLSv1.3];

Default:

proxy_ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;

Context:

http, server, location

Changed in version 1.2.0: TLSv1.3 parameter added to default set.

Enables the specified protocols for requests to a proxied HTTPS server.

proxy_ssl_server_name#

Syntax:

proxy_ssl_server_name on | off;

Default:

proxy_ssl_server_name off;

Context:

http, server, location

Enables or disables passing the server name set by the proxy_ssl_name directive via the Server Name Indication TLS extension (SNI, RFC 6066) while establishing a connection with the proxied HTTPS server.

proxy_ssl_session_reuse#

Syntax:

proxy_ssl_session_reuse on | off;

Default:

proxy_ssl_session_reuse on;

Context:

http, server, location

Determines whether SSL sessions can be reused when working with the proxied server. If the errors “SSL3_GET_FINISHED:digest check failed” appear in the logs, try disabling session reuse.

proxy_ssl_trusted_certificate#

Syntax:

proxy_ssl_trusted_certificate file;

Default:

Context:

http, server, location

Specifies a file with trusted CA certificates in the PEM format used to verify the certificate of the proxied HTTPS server.

proxy_ssl_verify#

Syntax:

proxy_ssl_verify on | off;

Default:

proxy_ssl_verify off;

Context:

http, server, location

Enables or disables verification of the proxied HTTPS server certificate.

proxy_ssl_verify_depth#

Syntax:

proxy_ssl_verify_depth number;

Default:

proxy_ssl_verify_depth 1;

Context:

http, server, location

Sets the verification depth in the proxied HTTPS server certificates chain.

proxy_store#

Syntax:

proxy_store on | off | string;

Default:

proxy_store off;

Context:

http, server, location

Enables saving of files to a disk.

on

saves files with paths corresponding to the directives alias or root

off

disables saving of files

The file name can be set explicitly using the string with variables:

proxy_store /data/www$original_uri;

The modification time of files is set according to the received “Last-Modified” response header field. The response is first written to a temporary file, and then the file is renamed. Temporary files and the persistent store can be put on different file systems. However, be aware that in this case a file is copied across two file systems instead of the cheap renaming operation. It is thus recommended that for any given location both saved files and a directory holding temporary files, set by the proxy_temp_path directive, are put on the same file system.

This directive can be used to create local copies of static unchangeable files, e.g.:

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

location /fetch/ {
    internal;

    proxy_pass         http://backend/;
    proxy_store        on;
    proxy_store_access user:rw group:rw all:r;
    proxy_temp_path    /data/temp;

    alias              /data/www/;
}

or like this:

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

location @fetch {
    internal;

    proxy_pass         http://backend;
    proxy_store        on;
    proxy_store_access user:rw group:rw all:r;
    proxy_temp_path    /data/temp;

    root               /data/www;
}

proxy_store_access#

Syntax:

proxy_store_access users:permissions …;

Default:

proxy_store_access user:rw;

Context:

http, server, location

Sets access permissions for newly created files and directories, e.g.:

proxy_store_access user:rw group:rw all:r;

If any group or all access permissions are specified then user permissions may be omitted:

proxy_store_access group:rw all:r;

proxy_temp_file_write_size#

Syntax:

proxy_temp_file_write_size size;

Default:

proxy_temp_file_write_size 8k|16k;

Context:

http, server, location

Limits the size of data written to a temporary file at a time, when buffering of responses from the proxied server to temporary files is enabled. By default, size is limited by two buffers set by the proxy_buffer_size and proxy_buffers directives. The maximum size of a temporary file is set by the proxy_max_temp_file_size directive.

proxy_temp_path#

Syntax:

proxy_temp_path path [level1 [level2 [level3]]]`;

Default:

proxy_temp_path proxy_temp;

Context:

http, server, location

Defines a directory for storing temporary files with data received from proxied servers. Up to three-level subdirectory hierarchy can be used underneath the specified directory. For example, in the following configuration

proxy_temp_path /spool/angie/proxy_temp 1 2;

a temporary file might look like this:

/spool/angie/proxy_temp/7/45/00000123457

See also the use_temp_path parameter of the proxy_cache_path directive.

Built-in Variables#

The http_proxy module supports built-in variables that can be used to compose headers using the proxy_set_header directive:

$proxy_host#

name and port of a proxied server as specified in the proxy_pass directive;

$proxy_port#

port of a proxied server as specified in the proxy_pass directive, or the protocol’s default port;

$proxy_add_x_forwarded_for#

the “X-Forwarded-For” client request header field with the $remote_addr variable appended to it, separated by a comma. If the “X-Forwarded-For” field is not present in the client request header, the $proxy_add_x_forwarded_for variable is equal to the $remote_addr variable.