NGINX server directives to reach an API - php

Question

I have a LEMP server and I'm looking to install RespondCMS (http://respondcms.com/documentation/install-on-digital-ocean). I'm running into some difficulties with the mod_rewrite section for an API. I've tried several iterations but have been unable to get it to show an "API works" message that indicates the PHP app is working. I get a 404. Thus far, I have settled on the following set-up in my /etc/nginx/sites-enabled/. I'm thinking it's not accessing the /api folder correctly. Any help in understanding how it's all interacting and how to make it work is appreciated.
app.domain.com
server {
listen 80;
server_name app.domain.com;
root /srv/www/domain_app/app;
index index.php index.html index.htm;
access_log /var/log/nginx/respond.access.log;
error_log /var/log/nginx/respond.error.log;
location /api/ {
try_files $uri $uri/ /api/dispatch.php$args;
}
location / {
try_files $uri $uri/ =404;
}
error_page 404 /404.html;
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root /srv/www;
}
location ~ \.php$ {
try_files $uri =404;
include fastcgi_params;
fastcgi_pass unix:/var/run/php5-fpm.sock;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
}
}
domain.com
server {
listen 80 default_server;
root /srv/www/html;
index index.php index.html index.htm;
server_name domain.com;
location / {
try_files $uri $uri/ =404;
}
error_page 404 /404.html;
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root /usr/share/nginx/html;
}
location ~ \.php$ {
try_files $uri =404;
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/var/run/php5-fpm.sock;
fastcgi_index index.php;
include fastcgi_params;
}
}

Answer 1

The URL http://app.domain.com/api/dispatch.php is processed by the location ~ \.(hh|php)$ block. And that block seems to be configured (reasonably) correctly.
You should move include fastcgi_params; above any fastcgi_param directive to avoid the latter being inadvertently overridden. And the fastcgi_index directive is redundant in this context.
Both the location / and location /api/ blocks have issues. The alias directive is unnecessary and wrong. All three locations inherit their root from the outer server block. You should delete both alias directives.
In your try_files $uri $uri/ $uri.php /api/dispatch.php$args; statement, the $uri.php element will cause the PHP file to be downloaded rather than executed. Only the last element of a try_files directive can take an action that is not processed within the same location block. If you really need to execute extension-less PHP URIs and have a default PHP URI too, you will probably need to use a named location.
A useful resource for all nginx directives is here.