Open Source Ecosystems

[!INFO] This project was previously called localhost.tools.

One time, you may want to run Docker containers locally and interact with them using domain names instead of 127.0.0.1:1234, for example. Additionally, you may want to use the HTTPS protocol. That’s what this project aims to provide.

[!WARNING] This project is under development and may not work as expected. For instance, the current implementation does not support WebSockets, gRPC, or other connection types - only HTTP/HTTPS is supported.

How does it work?

Technically, this project is a simple reverse proxy server. It listens to all incoming requests to domains like *.indocker.app and forwards them to the corresponding Docker containers running on your local machine. To make this work, I've registered the domain indocker.app and configured it so any subdomain points to your local machine (127.0.0.1 for IPv4 and ::1 for IPv6):

$ dig +noall +answer -t A foo.indocker.app # IPv4
foo.indocker.app.	7131	IN	A	127.0.0.1

$ dig +noall +answer -t AAAA foo.indocker.app # IPv6
foo.indocker.app.	86400	IN	AAAA	::1

$ dig +noall +answer foo.bar.baz.indocker.app # any depth
foo.bar.baz.indocker.app. 86400	IN	A	127.0.0.1

This eliminates the need for modifying the hosts file or using additional software to resolve domain names locally. All you need to do is run the indocker app and configure your Docker containers to be accessible via domain names using Docker labels.

Here’s an example of how the routing works:

You send an HTTP request to https://foo.indocker.app
foo.indocker.app resolves to 127.0.0.1 (your local machine)
The indocker app on your local machine (listening on ports 443 and 80) receives the request and forwards it to
the appropriate Docker container based on the domain name

[!INFO] More examples can be found in the examples directory.

What about HTTPS?

To enable HTTPS, I’ve generated a wildcard SSL certificate for the *.indocker.app domain, signed by Let's Encrypt. The indocker app uses this certificate to encrypt all incoming requests.

The certificate is automatically renewed periodically, and the app downloads it each time it starts, so you don’t need to worry about managing it.