nginx-elastic-client

To structure your elastic client command in your nginx proxy for multiple elasticsearch server.

Table of Contents

• Introduction
• Usage
• Installation
• Test
• Why need this
• Support
• Copyright & License

Introduction

nginx-elastic-client is a nginx module which allow to proxy to elastic server with given pre-defined/dynamic command.

Usage

0. Setup your elastic upstream

# nginx.conf
  upstream elastic_upstream {
     server 127.0.0.1:9200;
  }

1. Simple create index command, please noted that http method is defined inside command, it regardless what you called to nginx.

# nginx.conf

server {
    ....
   location /test {
        elastic_pass http://elastic_upstream;
        elastic_send PUT /testindex/testdoc/100;
        elastic_query '{
            "testname": "mytest"            
        }';
    }
}

2. If you don't want any command inside config, just pass ngixn variables to the elastic host, please setup the config below, you may refer the nginx variables for more details

# nginx.conf

server {
  ....
  
  location / {
      elastic_pass http://elastic_upstream;
      elastic_send $request_method $uri?$query_string; 
      elastic_query $request_body;
  }
}

3. Create index based on your args, for example /test?new_id=Staff1232

# nginx.conf

server {
    ....
   location /test {
        elastic_pass http://elastic_upstream;
        elastic_send PUT /testindex/testdoc/$arg_new_id;
        elastic_query '{
            "testname": "mytest-$arg_new_id"            
        }';
    }
}

4. search all

# nginx.conf

server {
    ....
   location /test {
        elastic_pass http://elastic_upstream;
        elastic_send POST /testindex/testdoc/_search/;
        elastic_query '{"query":
           {
            "match_all": {}
           }
        }';
    }
}

5. search all but group the docs by index.

# nginx.conf

server {
    ....
     location /test {
        elastic_pass http://elastic_upstream;
        elastic_send POST /testindex/testdoc/_search?size=100 index_docs;
        
        elastic_query '{"query":
           {
            "match_all": {}
           }
        }';
    }
}

6. search all but skipmeta data, keep index, type, and id.

# nginx.conf

server {
    ....
     location /test {
        elastic_pass http://elastic_upstream;
        elastic_send POST /testindex/testdoc/_search skipmeta;
        
        elastic_query '{"query":
           {
            "match_all": {}
           }
        }';
    }
}

7. search all but source only data.

# nginx.conf

server {
    ....
     location /test {
        elastic_pass http://elastic_upstream;
        elastic_send POST /testindex/testdoc/_search source;
        
        elastic_query '{"query":
           {
            "match_all": {}
           }
        }';
    }
}

8. search with dynamic input.

# nginx.conf

server {
    ....
    location /test {
        elastic_pass http://elastic_upstream;
        elastic_send POST /testindex/testdoc/_search;
        elastic_query $request_body;
    }

    location /test2 {
        elastic_pass http://elastic_upstream;
        elastic_send POST /testindex/testdoc/_search;
        elastic_query '{"query": {"match" : {"$arg_field" : "$arg_value"}}}';
    }
}

9. Delete index.

# nginx.conf

server {
    ....
    location /test {
        elastic_pass http://elastic_upstream;
        elastic_send DELETE /testindex/;
    }
}

Installation

wget 'http://nginx.org/download/nginx-1.13.7.tar.gz'
tar -xzvf nginx-1.13.7.tar.gz
cd nginx-1.13.7/

./configure --add-module=/path/to/nginx-elastic-client

make -j2
sudo make install

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Test

It depends on nginx test suite libs, please refer test-nginx for installation.

cd /path/to/nginx-elastic-client
export PATH=/path/to/nginx-dirname:$PATH 
sudo TEST_NGINX_SLEEP=0.3 prove t

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Why need this

Not everyone knows how to query elasticsearch, some client might prefer pass the argument rather than query themselves.

The query inside the nginx.conf has version controlled, maintained, tracked and it's transparent to every of your team member. Central based and pass to multiple elastic server.

Known issue faster, make change 1 to every client, if many client has their on client query logic, the issue will be hard to maintained.

Client can be Zero Down time! nginx -s reload make the changed.

Nginx is reliable proxy server, the client is auto load-balance upstream to elasticsearch server.

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Support

Please do not hesitate to contact minikawoon2017@gmail.com for any queries or development improvement.

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Copyright & License

Copyright (c) 2018, Taymindis cloudleware2015@gmail.com

This module is licensed under the terms of the BSD license.

All rights reserved.

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

1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. 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 OWNER 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.

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