nginx redirection depending on host - redirect

Question

I have two domains website1.com and website2.com linked to my server.
I'm trying to do the following rewrite rules:
http://website1.com/ --> /website1/ (static)
http://website2.com/ --> /website2/ (static)
http://website1.com/app/ --> http://localhost:8080/web-app/web1/
http://website2.com/app/ --> http://localhost:8080/web-app/web2/
The user will be redirected to a static website served by nginx or an application server depending on the url.
Here's what I tried so far:
location / {
root html;
index index.html index.htm;
if ($http_host = website1.com) {
rewrite / /website1/index.html break;
rewrite (.*) /website1/$1;
}
if ($http_host = website2.com) {
#same logic
}
}
location /app/ {
proxy_pass http://localhost:8080/web-app/;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
if ($http_host = website1.com) {
rewrite /app/(.*) /$1 break;
rewrite /app /index.html;
}
if ($http_host = website2.com) {
#same logic
}
}
The static part seems to work fine, but the redirection web app part seems to serve index.html no matter what the requested file is.

Answer 1

This is not much of a definitive answer, but rather just my explanation of how I get nginx proxies to work.
root html;
index index.html index.htm;
server {
listen 80;
server_name website1.com;
location / {
alias html/website1;
}
location /app/ {
proxy_pass http://localhost:8080/web-app/web1/
}
}
server {
listen 80;
server_name website2.com;
location / {
alias html/website2;
}
location /app/ {
proxy_pass http://localhost:8080/web-app/web2/
}
}
The issue looks like it's being caused by these rewrites:
rewrite /app/(.*) /$1 break;
rewrite /app /index.html;
Using server blocks with server_names and the alias directive, we can do away with needing to use that much logic. Let me know if there's anything that is still not clear.

Answer 2

I think you're doing it wrong. If there is so much difference between the hosts, it would be cleaner and more efficient to have two distinct configurations, one for each host.
On the other hand, if your intention is to have multiple almost-identical configurations, then the correct way to go about it might be map, and not if.
Back to your configuration — I've tried running it just to see how it works, and one thing that you may notice is that the path you specify within the proxy_pass effectively becomes a noop once the $host-specific rewrite within the same context gets involved to change the $uri — this is by design, and is very clearly documented within http://nginx.org/r/proxy_pass ("When the URI is changed inside a proxied location using the rewrite directive").
So, in fact, using the following configuration does appear to adhere to your spec:
%curl -H "Host: host1.example.com" "localhost:4935/app/"
host1.example.com/web-app/web1/
%curl -H "Host: host2.example.com" "localhost:4935/app/"
host2.example.com/web-app/web2/
%curl -H "Host: example.com" "localhost:4935/app/"
example.com/web-app/
Here's the config I've used:
server {
listen [::]:4935;
default_type text/plain;
location / {
return 200 howdy;
}
location /app/ {
proxy_set_header Host $host;
proxy_pass http://localhost:4936/web-app/;#path is NOOP if $uri get changed
if ($host = host1.example.com) {
rewrite /app/(.*) /web-app/web1/$1 break;
rewrite /app /web-app/index.html;
}
if ($host = host2.example.com) {
rewrite /app/(.*) /web-app/web2/$1 break;
rewrite /app /web-app/index.html;
}
}
}
server {
listen [::]:4936;
return 200 $host$request_uri\n;
}