fix: set http output contenttype to text/plain when json output is disabled

[FedeDP]

What type of PR is this?

/kind bug

Any specific area of the project related to this PR?

/area engine

What this PR does / why we need it:
The PR sets the http output Content-type header to a more meaningful value (text/plain) when json_output is disabled.

Which issue(s) this PR fixes:

Fixes #1824

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

fix: set http output contenttype to text/plain when json output is disabled

[leogr]

Hey @FedeDP

Thank you for this PR! We really need to fix that.
However, we shouldn't pass the formatter to the output channels. Moreover, if I understood correctly, your implementation won't work with internal messages (because they don't get a formatter). See my comment below.

I propose instead to propagate m_json_ouput to the output channels during init.

[leogr]

Could we avoid passing the formatter in the message?

This approach cannot work with internal messages, that do not have a formatter 👇

falco/userspace/falco/falco_outputs.cpp

Lines 199 to 213 in 226d1fb

	void falco_outputs::handle_msg(uint64_t ts,
	falco_common::priority_type priority,
	std::string &msg,
	std::string &rule,
	std::map<std::string, std::string> &output_fields)
	{
	falco_outputs::ctrl_msg cmsg = {};
	cmsg.ts = ts;
	cmsg.priority = priority;
	cmsg.source = "internal";
	cmsg.rule = rule;
	cmsg.fields = output_fields;
	if(m_json_output)
	{

Moreover, the JSON formatting option is a global setting (not a per-message setting) and the message already contains the formatted text. So I believe the formatter does not really belong to the message.

I would rather pass the m_json_output's value to each output via the init function 👇

falco/userspace/falco/falco_outputs.cpp

Line 138 in 226d1fb

oo->init(oc, m_buffered, m_hostname);

[FedeDP]

Much simpler, you're right! Thanks ;)

[leogr]

/approve

[poiana]

LGTM label has been added.

Git tree hash: efa6e71a68f1ba9ee93f1fae8d2e682838f0737a

[leogr]

/milestone 0.31.0

[jasondellaluce]

Thanks @FedeDP! ❤️

/approve

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: FedeDP, jasondellaluce, leogr

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