Symfony2: Dynamically generate URL protocol (HTTP/HTTPS) - symfony

I know many ways of forcing a route or a whole section to use either http or https:
http://symfony.com/doc/current/cookbook/routing/scheme.html
http://symfony.com/doc/current/cookbook/security/force_https.html
How to let Symfony 2 adopt the protocol scheme (http vs https)
...my question is: Is there a way for it to be decided dynamically?
By this, I mean, when I generate the url {{url('route_name'}} it generates a URL using the same protocol that the current page is using.
http://domain/index links to http://domain/route
https://domain/index links to https://domain/route

Related

On Demand TLS and Reverse Proxy Support for Custom Domains

I came into a situation today. Please share your expertise 🙏
I have a project (my-app.com) and one of the features is to generate a status page consisting of different endpoints.
Current Workflow
User login into the system
User creates a status page for one of his sites (e.g.google) and adds different endpoints and components to be included on that page.
System generates a link for a given status page.
For Example. my-app.com/status-page/google
But the user may want to see this page in his custom domain.
For Example. status.google.com
Since this is a custom domain, we need on-demand TLS functionality. For this feature, I used Caddy and is working fine. Caddy is running on our subdomain status.myserver.com and user's custom domain status.google.com has a CNAME to our subdomain status.myserver.com
Besides on-demand TLS, I am also required to do reverse proxy as
shown below.
For Example. status.google.com ->(CNAME)-> status.myserver.com ->(REVERSE_PROXY)-> my-app.com/status-page/google
But Caddy supports only protocol, host, and port format for reverse proxy like my-app.com but my requirement is to support reverse proxy for custom page my-app.com/status-page/google. How can I achieve this? Is there a better alternative to Caddy or a workaround with Caddy?
You're right, since you can't use a path in a reverse-proxy upstream URL, you'd have to do rewrite the request to include the path first, before initiating the reverse-proxy.
Additionally, upstream addresses cannot contain paths or query strings, as that would imply simultaneous rewriting the request while proxying, which behavior is not defined or supported. You may use the rewrite directive should you need this.
So you should be able to use an internal caddy rewrite to add the /status-page/google path to every request. Then you can simply use my-app.com as your Caddy reverse-proxy upstream. This could look like this:
https:// {
rewrite * /status-page/google{path}?{query}
reverse_proxy http://my-app.com
}
You can find out more about all possible Caddy reverse_proxy upstream addresses you can use here: https://caddyserver.com/docs/caddyfile/directives/reverse_proxy#upstream-addresses
However, since you probably can't hard-code the name of the status page (/status-page/google) in your Caddyfile, you could set up a script (e.g. at /status-page) which takes a look at the requested URL, looks up the domain (e.g. status.google.com) in your database, and automatically outputs the correct status-page.

Building URLs in Go including server scheme

I am creating a REST API in Go, and I want to build URLs to other resources in my replies.
Based on the http.Response I can get the Host and URL.
However, how would I go about getting the transport scheme used by the server? http or https?
I attemped to check if server.TLSConfig is nil and then assuming it is using http since it says this in the documentation for http.Server:
TLSConfig *tls.Config // optional TLS config, used by ListenAndServeTLS
But it turns out this exists even when I do not run the server with ListenAndServeTLS.
Or is this way of building my URLs the wrong way of doing things? Is there some other normal way of doing this?
My preferred solution when running http and https is just to run a simple listener on :80 that redirects all traffic to https. Then any real traffic can be assumed to be https.
Alternately I believe you can access a request's URL at req.URL.Scheme to see the protocol.
Or do you mean for the entire application? If you accept configuration to switch between http and https, then can't you look at that and see which they chose? I guess I'm missing some context maybe.
It is also common practice for apps to take a baseURL via flag or config to generate external urls with.

Difference Between // and http://

I know that HTTP is hyper text transfer protocol, and I know that's how (along with HTTPS) one accesses a website. However, what does just a // do? For instance, to access Google's copy of jQuery, one would use the url //ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js, as opposed to http://....
What exactly is the difference? What does just // indicate?
Thanks.
By saying on // it means use whatever protocol (IE: http vs https) your user is currently hittin for that resource.
So you don't have to worry about dealing with http: vs https: management yourself.
Avoiding potential browser security warnings. It would be good practice to stick with this approach.
For example: If your user is accessing http://yourdomain/ that script file would automatically be treated as http://ajax.googleapis.com/...
if your current request is http
//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js
will be treated as
http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js
if your current request is https
//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js
will be treated as
https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js

Track http reference on https site using fiddler

I have a site https://mysite.com which deals with various portlets, gadgets. One of the gadget must be referring to http instead of https.
I would'nt know which one just by view source I want to use fiddler. Can some one explain me how do I use it to track http reference?
Sure. Boot up Fiddler and enabled HTTPS decryption. Then visit your site and let the page load. Then look at the Protocol column in Fiddler's main session list. One of them will say HTTP instead of HTTPS.

Best method of post processing Nginx reverse proxy response

I'm doing some researching on switching from Apache to Nginx as a reverse proxy in front of a Grails application on the backend. I'm playing around with some URL rewriting and have run into an issue with the response being sent back from my back end. I can handle the location header rewrite but I'm wondering what the best way to process the actually content is for link and such.
Is nginx_substitutions_filter the preferred method or is there another module that folks use to do content replacement in the response body?
I've thought about creating a Grails plugin to handle rendering the correct content based on additional request headers but now I'm thinking that would be best handled outside the application to allow for the most flexibility and loose coupling.
Are there any articles about best practices for doing URL rewriting/response post processing for reverse proxy scenarios?
You can use the Lua module to capture the response and manipulate it like a Lua string. Silly example to upper case the output:
res = ngx.location.capture('/some/path')
ngx.print(string.upper(res.body))
see http://wiki.nginx.org/HttpLuaModule#ngx.location.capture
If you want to replace only the headers, HeadersMore 3rd party module is great for that.
Other than that, susbstiution module seems to be the only option.
But I would suggest you make the backend return the correct page. Modifying every response uses resources and takes time.

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