Certain HTML can be rejected by nokogumbo, specifically cases where there
are enormous amounts of attributes
This ensures that malformed HTML is simply skipped instead of leaking out
an exception and terminating downstream processes.
```
WARNING: Using `expect { }.not_to raise_error(SpecificErrorClass)` risks false positives, since literally any other error would cause the expectation to pass, including those raised by Ruby (e.g. `NoMethodError`, `NameError` and `ArgumentError`), meaning the code you are intending to test may not even get reached. Instead consider using `expect { }.not_to raise_error` or `expect { }.to raise_error(DifferentSpecificErrorClass)`. This message can be suppressed by setting: `RSpec::Expectations.configuration.on_potential_false_positives = :nothing`. Called from /var/www/discourse/spec/lib/retrieve_title_spec.rb:155:in `block (3 levels) in <main>'.
```
This PR changes the rescue block to rescue only Net::TimeoutError exceptions and removes the log line to prevent clutter the logs with errors that are ignored. Other errors can bubble up because they're errors we probably want to know about
If the crawled page returned an error, `FinalDestination#safe_get`
yielded `nil` for `uri` and `chunk` arguments. Another problem is that
`get` did not handle the case when `safe_get` failed and did not return
the `location` and `set_cookie` headers.
The `blocked onebox domains` setting lets site owners change what sites
are allowed to be oneboxed. When a link is entered into a post,
Discourse checks the domain of the link against that setting and blocks
the onebox if the domain is blocked. But if there's a chain of
redirects, then only the final destination website is checked against
the site setting.
This commit amends that behavior so that every website in the redirect
chain is checked against the site setting, and if anything is blocked
the original link doesn't onebox at all in the post. The
`Discourse-No-Onebox` header is also checked in every response and the
onebox is blocked if the header is set to "1".
Additionally, Discourse will now include the `Discourse-No-Onebox`
header with every response if the site requires login to access content.
This is done to signal to a Discourse instance that it shouldn't attempt
to onebox other Discourse instances if they're login-only. Non-Discourse
websites can also use include that header if they don't wish to have
Discourse onebox their content.
Internal ticket: t59305.
It's very easy to forget to add `require 'rails_helper'` at the top of every core/plugin spec file, and omissions can cause some very confusing/sporadic errors.
By setting this flag in `.rspec`, we can remove the need for `require 'rails_helper'` entirely.