Configurable basepath/url for nginx reverse proxing on diff location other than /?

[michailsal]

Is there any way to configure caravel to accept requests under /my-whatever-path/.....? I would like to reverse proxy caravel using nginx but not on / location block.

[xrmx]

Google suggests this http://flask.pocoo.org/snippets/35/ . Feel free to open a pull request if it works for you.

[michailsal]

It did work, but then I ran into countless absolute links that I haven't found a way to put them behind a prefix. Any ideas?

[xrmx]

@michailsal does url_for work correctly? If so it is just matter or using it thoroughly.

[michailsal]

url_for does work for the most part, but still there are many hardcoded absolute links e.g.

./templates/caravel/sql.html:      <img id="loading" width="25" style="display: none;" src="/static/assets/images/loading.gif">
./templates/caravel/welcome.html:          <img class="loading" src="/static/assets/images/loading.gif"/>
./templates/caravel/explore.html:            <img src="{{ url_for("static", filename="assets/images/loading.gif") }}" class="loading" alt="loading">
./templates/caravel/standalone.html:      <img src="{{ url_for("static", filename="img/loading.gif") }}" class="loading" alt="loading">

Shall I just fix them by adding url_for (which I have already done locally) and open a pull request?

[xrmx]

@michailsal yes, please!

[cuph62]

Is there any news regarding these changes / pull request ?

The same issue applies on wsgi serving with Apache for example:
in apache config:
WSGIScriptAlias /myapp /var/www/dashboard/flaskacct.wsgi

but immediately I get a 404 with http://myhost/caravel/welcome without preserving the baseurl like
http://myhost/myapp/caravel/welcome.

[michailsal]

I haven't had time to work on this, I do know though that even if somehow you manage to preserve the baseurl and not being redirected, there are still many absolute links pointing to "/" instead of using "url_for"

[andreaslang]

Somewhat related to this, I did a brute force thing with apache to get it (almost) working:

ProxyPass /caraveldata/ http://caravel:8088/
ProxyPassReverse /caraveldata/ http://caravel:8088/

<Location /caraveldata/>
    Header edit Location ^https?://([^/]+)/(.*)$ https://$1/caraveldata/$2

    RequestHeader unset Accept-Encoding
    ProxyHTMLEnable On
    ProxyHTMLExtended On
    ProxyHTMLURLMap / /caraveldata/
    ProxyHTMLURLMap /caraveldata/ /caraveldata/
</Location>

This almost works, but then I run into issues with JavaScript, because it does things like for example in welcome.js:

// Builds a dataTable from a flask appbuilder api endpoint
let url = '/' + modelView.toLowerCase() + '/api/read';

I don't see a good way of fixing that, without touching caravel source code in quite a few places. I am considering to introduce another sub-domain to be able to proxy my backend caravel app without the need to use paths. I was just trying to avoid it because another sub-domain means I need to separately configure it with our single-sing-on.

[rsxm]

Is anyone working this? I just tried to put Gunicorn (serving Superset) behind an nginx proxy. Some links work, but others didn't.

This is relevant part from my nginx config file:

location /prefix/ {
proxy_pass http://172.26.0.4:8088/prefix/; # <- gunicorn server
proxy_set_header SCRIPT_NAME /prefix;
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

In Superset, I tried with and without ENABLE_PROXY_FIX (not sure what this setting does?).
So without digging deeper, it looks like the issue is still hardcoded urls?

[joharohl]

I have made a proof of concept that works behind a proxy.

The python code changes were fairly straightforward by switching hard coded urls for Flasks' url_for.

The JS though... I just did the hacky thing by templating serverRoot and staticRoot global js variables that are then used to build the urls. It works fine, but is probably not the best.

I would love to contribute this back, but need some guidance on how to approach the JS side of things.

[xrmx]

@joharohl if we have the code i'd say to just open a PR for the python code and we can discuss about the js. We can update the PR later or just open a new one.

[mistercrunch]

related #3690