Introduce an attribute "contents"

[SarthakMakhija]

Provide support for "contents" attribute. This attribute represents the contents of a file.

Sample queries using contents attribute

select * from . where like(contents, LengthFunctionBlock)
select * from . where like(contents, TrimFunctionBlock)

Constraints

1. contents MUST be a lazily evaluated attribute. Refer AttributeLazyEvaluationBlock.go to understand lazy evaluation
2. Once contents is evaluated it must be set in FileAttributes object
3. contents MUST be evaluated only for text files
4. contents MUST be evaluated only for text files if the size is less than 20 Mib, else set an empty string in FileAttributes object
5. Add tests to cover evaluation of contents at least for text files, hidden files that are text files, an image file, a doc and a pdf file

Necessary details

1. New attributes are onboarded in Attributes.go
2. FileAttributes.go acts as a wrapper over fileInfo

Reference

1. Refer mimeType attribute for lazy evaluation in Attributes.go and FileAttributes.go

[PankhudiB]

Hello, can I work on this under Hacktoberfest'22 ?

[SarthakMakhija]

Hey @PankhudiB

This issue has already been picked by someone .. If you are want, you may take a look at this and see if this interests you.