data_readstringarray
Prototype: data_readstringarray(filename, comment, split, maxentries, maxbytes)
Return type: data
Description: Returns a data container (map) with up to
maxentries
-1 fields from the first maxbytes
bytes of file
filename
. The first field becomes the key in the map.
One dimension is separated by the regex split
, the other by the
lines in the file. The array key (the first field) must be unique; if
you need to allow duplicate lines use data_readstringarrayidx()
.
The comment
field is a multiline regular expression and will strip out
unwanted patterns from the file being read, leaving unstripped characters to be
split into fields. Using the empty string (""
) indicates no comments.
Arguments:
filename
:string
, in the range:"?(/.*)
comment
:string
, in the range:.*
split
:string
, in the range:.*
maxentries
:int
, in the range:0,99999999999
maxbytes
:int
, in the range:0,99999999999
Example:
Prepare:
echo a,b,c > /tmp/cfe_array
echo "# This is a comment" >> /tmp/cfe_array
echo d,e,f >> /tmp/cfe_array
echo g,h,i >> /tmp/cfe_array
echo "# This is another comment" >> /tmp/cfe_array
echo j,k,l >> /tmp/cfe_array
Run:
body common control
{
bundlesequence => { "example" };
}
bundle agent example
{
vars:
# The comment regex warrents an explination:
# # matches the character # literally
# [^\n]* match a single character not including the newline character
# between zero and unlimited times, as many times as possible
"bykey" data => data_readstringarray("/tmp/cfe_array","#[^\n]*",",",10,400);
"byint" data => data_readstringarrayidx("/tmp/cfe_array","#[^\n]*",",",10,400);
"bykey_str" string => format("%S", bykey);
"byint_str" string => format("%S", byint);
reports:
"By key: $(bykey_str)";
"specific element by key a, offset 0: '$(bykey[a][0])'";
"By int offset: $(byint_str)";
"specific element by int offset 2, 0: '$(byint[2][0])'";
}
Output:
R: By key: {"a":["b","c"],"d":["e","f"],"g":["h","i"],"j":["k","l"]}
R: specific element by key a, offset 0: 'b'
R: By int offset: [["a","b","c"],["d","e","f"],["g","h","i"],["j","k","l"]]
R: specific element by int offset 2, 0: 'g'
See also: data_readstringarrayidx()
, data