NIFI-2859 - Ignore files starting with a dot in ListHDFS

[pvillard31]

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[bbende]

I think we should try to be consistent with how ListFile works. It has a property to apply a regex to filer filenames and the default value is anything that doesn't start with a dot:

public static final PropertyDescriptor FILE_FILTER = new PropertyDescriptor.Builder()
            .name("File Filter")
            .description("Only files whose names match the given regular expression will be picked up")
            .required(true)
            .defaultValue("[^\\.].*")
            .addValidator(StandardValidators.REGULAR_EXPRESSION_VALIDATOR)
            .build();

This way the user can determine if they want dot files or not.

[pvillard31]

@bbende Yes you're right! Otherwise there is the following in GetHDFS:

public static final PropertyDescriptor IGNORE_DOTTED_FILES = new PropertyDescriptor.Builder()
    .name("Ignore Dotted Files")
    .description("If true, files whose names begin with a dot (\".\") will be ignored")
    .required(true)
    .allowableValues("true", "false")
    .defaultValue("true")
    .build();

But the filter property is much better. I'll update the PR.

[pvillard31]

@bbende: I added the file filter property as suggested.

[trixpan]

@pvillard31 @bbende LGTM

[joewitt]

+1 merged to master