[Fleet] Invalid agent YAML is generated when quoted text fields are numeric

[adriansr]

Kibana version: 7.13+ / 8.0

Describe the bug:

Saving a policy fails due to YAML error when a policy variable of type text has a numeric value and it's used inside a quoted string in the package's yml.hbs template.

Steps to reproduce:

• Package defines a configuration variable, my_var of type text.
• Agent hbs template uses this variable between quotes:

value: "{{my_var}}"

-or-

host: "{{my_var}}:8080"

• Configure the package with a numeric value, 1234 or 0xABC.
• Saving the policy results in an error (actual error msg may depend on context):

  Error

  can not read a block mapping entry; a multiline key may not be an implicit key

Expected behavior:

No error.

Examples:

This bug is exhibited by the Zoom package (latest version 0.6.0, 0.3.1 in cloud) when setting the Zoom verification token (secret_value variable):

Also the Bluecoat Director package and many others that build a "host:port" string from two separate variables:

[elasticmachine]

Pinging @elastic/fleet (Team:Fleet)

[elasticmachine]

Pinging @elastic/fleet (Feature:Fleet)

[adriansr]

I think this may be introduced by #90371 which fixed #89955. Not sure if it'll be possible to fix this or we need to be more careful when quoting variables in packages to avoid this problem.

/cc @jen-huang

[jen-huang]

Thanks for the thorough report @adriansr, I recall we had a few issues similar to this in the past. We'll take a look!

[nchaulet]

I think I could have solution that will work but it will require to make a change to the integrations that are expecting a string value

You can use !!str in a yaml file to force the yaml parser to get the value as a string

So if integration template look like this my_value: !!str {{test}} we could ensure the value will be a string without adding the extra quote.

Example:

For this to work we will have to update integrations expecting a string osquery? and revert #90371

@elastic/integrations @aleksmaus what do you think of this solution?

[aleksmaus]

@nchaulet we changed osquery configuration in particular for the next 7.16 release (6.x version of osquery_manager integration), not using streams and the hbs template for them anymore