Add Vary header for correct fixing of CORS headers#14
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LukasKalbertodt wants to merge 1 commit intomainfrom
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Add Vary header for correct fixing of CORS headers#14LukasKalbertodt wants to merge 1 commit intomainfrom
Vary header for correct fixing of CORS headers#14LukasKalbertodt wants to merge 1 commit intomainfrom
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When the server's `Access-Control-Allow-Origin` header depends on the incoming `Origin` header, then the server should also set `Vary: Origin`. Otherwise, browsers are allowed to cache the response (made from one origin) and use it when another origin requests the same file. But then the `Allow-Origin` does not match the second one, leading to a CORS error. With this header, the browser must cache the response separately for each origin. This of course has some disadvantages, as there will be more cache misses. It's not ideal, but the previous config can lead to very broken behavior in some situations. As an aside: if I understand the config correctly, if `opencast_nginx_cors_urls` are not set, then the cors headers always say "allow" to whatever origin. Is that really intended? Seems potentially dangerous that leaving away this config value opens up CORS to everyone.
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When the server's
Access-Control-Allow-Originheader depends on the incomingOriginheader, then the server should also setVary: Origin. Otherwise, browsers are allowed to cache the response (made from one origin) and use it when another origin requests the same file. But then theAllow-Origindoes not match the second one, leading to a CORS error. With this header, the browser must cache the response separately for each origin. This of course has some disadvantages, as there will be more cache misses. It's not ideal, but the previous config can lead to very broken behavior in some situations.As an aside: if I understand the config correctly, if
opencast_nginx_cors_urlsare not set, then the cors headers always say "allow" to whatever origin. Is that really intended? Seems potentially dangerous that leaving away this config value opens up CORS to everyone.