Docker Communication between 2 apps inside same container - docker

Question

I have two apps -- app1 is running on localhost/app1. app2 which exposes api is running on localhost/app2 .Both these apps uses nginx server. App1 is makes an HTTP GET request to app2, which throws cURL error 7: Failed to connect.
But when containerizing both of these apps (and running them on the same network), what url should app1 be sending to fetch the api details?
Docker-compose.yml
version: '2'
services:
web:
image: nginx
ports:
- "83:80"
- "443:443"
links:
- php
volumes:
- /code:/var/www/html
php:
build:
context: .
dockerfile: ./Dockerfile
volumes:
- /code:/var/www/html
Code Directory has 2 folders app1 and app2, Where app1 is the application code base and app2 is the api code base
Virutalhost entry mounted inside web container
server {
listen 80;
server_name default;
root /var/www/html;
index index.html index.php;
client_max_body_size 100M;
fastcgi_read_timeout 1800;
location / {
try_files $uri $uri/ /index.php$is_args$args;
}
location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
expires max;
log_not_found off;
access_log off; }
location ~ \.php$ {
try_files $uri =404;
include fastcgi_params;
fastcgi_index index.php;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
fastcgi_pass lamp_php_1:9000;
}
}