Search engines like Google, DuckDuckGo, Baidu and Yandex do a great job crawling and indexing your web sites and applications. However, this is not so great when you accidentally publish a development version of your app.
In Symfony 4.3 we improved this situation by disallowing the search engine
indexing for development applications. How does it work? If the app kernel
runs in debug mode (by default this happens when the Symfony environment is
not prod) Symfony adds a X-Robots-Tag: noindex HTTP header to all the
responses.
The X-Robots-Tag header is one of the HTTP headers that legit search engines take into account when crawling a web site. If your own app already added that header, this new feature doesn't change its value. Also, if you don't like this feature, you can disable it with this config option:
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# config/packages/framework.yaml
framework:
# ...
disallow_search_engine_index: false
Nice feature !
It's good protection, I usually add this manually to Nginx for demo environment.
Actually it's smart, we had the case in the past :x
I think the value should be "true"
value of disallow_search_engine_index is false. then it should be allow search engine index, WDYT?
About the value of this option:
By default it has the same value as "debug". So if your app is in debug mode (dev environment) then it's true. If your app is not in debug mode (prod environment) then it's false.
The option name is negative ... so "true" means: "protect my site and don't index it".
So, if you don't like this option, you must use "false" to say: "don't protect my site".
Nice