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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Hello !<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I'm trying to get up a reverse proxy where my users can pass in a url of the form<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-indent:.5in"><span style="font-size:11.0pt">https://my.server.com?https://some.other.server.com<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">and it'll proxy to it.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">It works perfectly with this configuration with the proxy_pass target hard coded:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">```<br>
server {<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> server_name my.server.com;
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> listen [::]:443 ssl ipv6only=on; # managed by Certbot<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> listen 443 ssl; # managed by Certbot<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> location / {<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> <b>proxy_pass https://some.other.server.com;<o:p></o:p></b></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header Cache-Control "public, max-age=3";<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header 'Access-Control-Allow-Origin' "$http_origin";<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header 'X-Frame-Options' "ALLOW FROM $http_origin";<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header 'Access-Control-Allow-Credentials' 'true';<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header 'Vary' 'Origin';<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">```<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">testing with:<br>
> curl -X POST <b>https://my.server.com </b>-H "Content-Type: application/json" -d "{\"id\": \"123\"}"<br>
<br>
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">But if I swap out the proxy_pass target with a variable, I'm getting a 502 Bad Gateway.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">```<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">server {<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> server_name my.server.com;
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> listen [::]:443 ssl ipv6only=on; # managed by Certbot<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> listen 443 ssl; # managed by Certbot<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> location / {<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> <b>proxy_pass $args;<o:p></o:p></b></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header Cache-Control "public, max-age=3";<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header 'Access-Control-Allow-Origin' "$http_origin";<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header 'X-Frame-Options' "ALLOW FROM $http_origin";<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header 'Access-Control-Allow-Credentials' 'true';<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> add_header 'Vary' 'Origin';<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">```<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Testing with:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">> curl -X POST <b>https://my.server.com?https://some.other.server.com</b> -H "Content-Type: application/json" -d "{\"id\": \"123\"}"<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I'm writing the $args out to the logs:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">log_format main 'ARGS: >>$args<<';<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">access_log /var/log/nginx/access.log main;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">and it looks fine."$args" is identical to what I had hard coded, so I know that "args" is exactly the url I want to proxy_pass to.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">My location is not a regular expression and according to the docs [1], variables in proxy_pass should be fair game?<br>
<br>
-----<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">When variables are used in </span>
<span style="font-size:10.0pt;font-family:"Courier New"">proxy_pass</span><span style="font-size:11.0pt">:
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">location /name/ {<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New""> proxy_pass http://127.0.0.1$request_uri;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">}<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">In this case, if URI is specified in the directive, it is passed to the server as is, replacing the original request URI.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">-----<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Any help is much appreciated !<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Jeff<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">[1] <a href="https://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_pass">
https://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_pass</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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