I am very new to nginx. So I managed to setup with a lot of googling ready.
I have one pure php app running on this folder /var/www/html/app1

Next I want to build api links. So first I did this

composer create-project slim/slim-skeleton

I want to use the slim framework.So the slim-skeleton folder I renamed it as apitest. Next I adjusted my nginx config file its as below. Below I added this configuration

location /apitest {
alias /var/www/html/apitest1/public;
try_files $uri $uri/ /index.php$is_args$args;

location ~ \.php$ {
include fastcgi.conf;
fastcgi_param SCRIPT_FILENAME $request_filename;
fastcgi_pass 127.0.0.1:9000;
}
}
but I keep getting 404 not found.

Below is my full nginx.conf file.

user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;

# Load dynamic modules. See /usr/share/nginx/README.dynamic.
include /usr/share/nginx/modules/*.conf;

events {
worker_connections 1024;
}

http {
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
server_tokens off;
access_log /var/log/nginx/access.log main;

sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;

include /etc/nginx/mime.types;
default_type application/octet-stream;

# Load modular configuration files from the /etc/nginx/conf.d directory.
# See http://nginx.org/en/docs/ngx_core_module.html#include
# for more information.
include /etc/nginx/conf.d/*.conf;
include /etc/nginx/blockuseragents.rules;
limit_conn_zone $binary_remote_addr zone=addr:5m;
server {
listen 80 default_server;
listen [::]:80 default_server;
server_name _;
#root /usr/share/nginx/html;
root /var/www/html;

# Load configuration files for the default server block.
include /etc/nginx/default.d/*.conf;



error_page 404 /404.html;
location = /40x.html {
}

error_page 500 502 503 504 /50x.html;
location = /50x.html {
}
if ($request_method !~ ^(GET|HEAD|POST)$) {
return 444;
}
limit_conn addr 1;

location /apitest {
alias /var/www/html/apitest1/public;
try_files $uri $uri/ /index.php$is_args$args;

location ~ \.php$ {
include fastcgi.conf;
fastcgi_param SCRIPT_FILENAME $request_filename;
fastcgi_pass 127.0.0.1:9000;
}
}


}