[nginx-announce] njs-0.5.3

[Dmitry Volyntsev]

Hello,

I'm glad to announce a new release of NGINX JavaScript module (njs).

This release focuses on extending the modules functionality.

Notable new features:
- js_var directive. The directive creates an nginx variable writable
     from njs. The variable is not overwritten after a redirect unlike
     variables created with the set directive.

     This is especially useful in situations where some directive value
     depends on the result of a subrequest.

     The following example illustrates the case where Authorization header
     is processed by a HTTP endpoint which returns foo value as a result.
     This result is passed as a header to the backend.

: nginx.conf:
:   js_import main.js;
:
:   js_var $foo;
:   ..
:
:   location /secure/ {
:       auth_request /set_foo;
:
:       proxy_set_header Foo $foo;
:       proxy_pass http://backend;
:   }
:
:  location =/set_foo {
:       internal;
:       js_content main.set_foo;
:  }
:
: main.js:
:   function set_foo(r) {
:        ngx.fetch('http://127.0.0.1:8080', {headers: {Authorization: r.headersIn.Authorization}})
:        .then(reply => {
:            r.variables.foo = reply.headers.get('foo');
:            r.return(200);
:        });
:   }
:
:   export default {set_foo};

You can learn more about njs:

- Overview and introduction: http://nginx.org/en/docs/njs/
- Presentation: https://youtu.be/Jc_L6UffFOs
- Using node modules with njs:
http://nginx.org/en/docs/njs/node_modules.html
- Writing njs code using TypeScript definition files:
    http://nginx.org/en/docs/njs/typescript.html

Feel free to try it and give us feedback on:

- Github: https://github.com/nginx/njs/issues
- Mailing list: http://mailman.nginx.org/mailman/listinfo/nginx-devel


Changes with njs 0.5.3                                        30 Mar 2021

     nginx modules:

     *) Feature: added the "js_var" directive.