Introduction

Like other programming platforms, nginx can also declare variables in a very simple way

Implementation method

We can use the set directive to declare variables. We will have 3 types of variables:

• String
• Integer
• Boolean

We will have the declaration structure as follows

set $<variable_name> <variable_value>;

Example

# set name "Farhan"

# set age 25

# set is_working true

In addition, nginx also has a built-in variable system that allows us to use at any time.

Example

events {

}

http {
  server {
      listen 80;
      server_name nglearns.test;
      return 200 "Host - $host\nURI - $uri\nArgs - $args\n";
  }
}

Performing request

# curl http://nglearns.test/user?name=Farhan

Result

# Host - nglearns.test

# URI - /user

# Args - name=Farhan

In the example above, the variables $host and $uri have values related to the root address and URI, and the variable $args shows all Search Query Params on the URL.

In case you need to retrieve a specific value of Search Query Params, follow the example below:

events {

}

http {
  server {
    listen 80;
    server_name nglearns.test;
    set $name $arg_name;
    return 200 "Name - $name\n";
  }

}

Try querying

curl http://nglearns.test?name=Farhan

result

# Name - Farhan

In the example above, we can easily retrieve the name information separately.