Name
ngx_rds_json - an output filter that formats Resty DBD Streams generated by ngx_drizzle and others to JSON
Table of Contents
- Name
- Status
- Synopsis
- Description
- Directives
- Installation
- Compatibility
- Author
- Copyright & License
- See Also
Status
This module is considered production ready.
We need your help! If you find this module useful and/or interesting, please consider joining the development! Commit bit can be freely delivered at your request ;)
Synopsis
server {
location /mysql {
drizzle_query 'select * from cats';
drizzle_pass my_mysql_upstream;
rds_json on;
}
location /foo {
if ($arg_limit !~ '^\d{2}$') {
rds_json_ret 400 'Bad "limit" argument';
}
drizzle_query "select * from dogs limit $arg_limit";
drizzle_pass my_mysql_upstream;
rds_json on;
}
...
}Description
This module provides an output filter that can format the RDS outputs generated by ngx_drizzle and ngx_postgres modules to JSON.
Directives
rds_json
syntax: rds_json on|off
default: rds_json off
context: http, server, location, if location
Enables or disables the output filter of this module.
rds_json_buffer_size
syntax: rds_json_buffer_size <bytes>
default: rds_json_buffer_size <page-size>
context: http, server, location, if location
Controls the buffer size used by this module. default to the page size (4k/8k). The bigger the buffer size, the less streammy the conversion will be. But usually increasing the buffer size does help reduce CPU time.
rds_json_format
syntax: rds_json_format normal|compact
default: rds_json_format normal
context: http, server, location, if location
Controls the output JSON format. A sample of the default "normal" format looks like this
[{"id":1,"name":"marry"},{"id":2,"name":"bob"}]while it looks like below when in the "compact" format
[["id","name"],[1,"marry"],[2,"bob"]]that is, the first row holds the column name list.
rds_json_root
syntax: rds_json_root <key>
default: no
context: http, server, location, if location
Specifies the "root" key for data rows (if any). For example,
rds_json on;
rds_json_root rows;will return JSON output like this:
{"rows":[{"id":2,"name":null},{"id":3,"name":"bob"}]}if rds_json_format compact is also specified, then the
output will look like this:
{"rows":[["id","name"],[2,null],[3,"bob"]]}Nginx variables are not supported in the argument of this directive.
If this directive is not defined, neither are rds_json_success_property, nor rds_json_user_property, the JSON output for select queries will just be an array at the top level.
When either rds_json_success_property or rds_json_user_property are specified, this directive takes a default argument of "data".
rds_json_success_property
syntax: rds_json_success_property <key>
default: no
context: http, server, location, if location
Specifies the top-level object property name used in the JSON output for indicating success or false of the query.
rds_json_user_property
syntax: rds_json_user_property <key> <value>
default: no
context: http, server, location, if location
Specifies additonal user properties for the top-level object of the JSON output.
Multiple instances of this directives are allowed in a single scope.
Nginx variables are supported in the value argument.
Both of the key and value arguments will be automatically
quoted according to JSON strings' notation.
rds_json_errcode_key
syntax: rds_json_errcode_key <key>
default: rds_json_errcode_key errcode
context: http, server, location, if location
Specifies the errcode key name used in the JSON output.
rds_json_errstr_key
syntax: rds_json_errstr_key <key>
default: rds_json_errstr_key errstr
context: http, server, location, if location
Specifies the errstr key name used in the JSON output.
rds_json_ret
syntax: rds_json_ret <error-code> <descrption>
default: no
context: location, if location
This directive enables a content handler that simply emits an response body like this:
{"errcode":<error-code>,"errstr":"<description>"}while the <description> string will be properly quoted as
a JSON string.
rds_json_content_type
syntax: rds_json_content_type <mime-type>
default: rds_json_content_type application/json
context: http, server, location, if location
Controls the Content-Type header of the response generated by
this module's output filter.
Installation
You're recommended to install this module (as well as the Nginx core and many other goodies) via the OpenResty bundle. See the detailed instructions for downloading and installing OpenResty into your system. This is the easiest and most safe way to set things up.
Alternatively, you can install this module manually with the Nginx source:
Grab the nginx source code from nginx.org, for example, the version 1.13.6 (see nginx compatibility), and then build the source with this module:
$ wget 'http://nginx.org/download/nginx-1.13.6.tar.gz'
$ tar -xzvf nginx-1.13.6.tar.gz
$ cd nginx-1.13.6/
# Here we assume you would install you nginx under /opt/nginx/.
$ ./configure --prefix=/opt/nginx \
--add-module=/path/to/rds-json-nginx-module
$ make -j2
$ make installDownload the latest version of the release tarball of this module from rds-json-nginx-module file list.
Starting from NGINX 1.9.11, you can also compile this module as a dynamic module, by using the --add-dynamic-module=PATH option
instead of --add-module=PATH on the ./configure command line above.
And then you can explicitly load the module in your nginx.conf via the load_module directive, for example,
load_module /path/to/modules/ngx_http_rds_json_filter_module.so;Also, this module is included and enabled by default in the OpenResty bundle.
Compatibility
The following versions of Nginx should work with this module:
- 1.13.x (last tested: 1.13.6)
- 1.12.x
- 1.11.x (last tested: 1.11.2)
- 1.10.x
- 1.9.x (last tested: 1.9.7)
- 1.8.x
- 1.7.x (last tested: 1.7.10)
- 1.6.x
- 1.5.x (last tested: 1.5.12)
- 1.4.x (last tested: 1.4.4)
- 1.2.x (last tested: 1.2.9)
- 1.1.x (last tested: 1.1.5)
- 1.0.x (last tested: 1.0.9)
- 0.9.x (last tested: 0.9.4)
- 0.8.x (last tested: 0.8.55)
- 0.7.x >= 0.7.46 (last tested: 0.7.68)
Earlier versions of Nginx like 0.6.x and 0.5.x will not work.
If you find that any particular version of Nginx above 0.7.44 does not work with this module, please consider reporting a bug.
Author
Yichun "agentzh" Zhang (η« δΊ¦ζ₯) <[email protected]>, OpenResty Inc.
Copyright & License
This module is licenced under the BSD license.
Copyright (C) 2009-2017, Yichun Zhang (agentzh) <[email protected]>, OpenResty Inc.
All rights reserved.
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.