Parse a fixed width-encoded field into known columns. It can parse values of the form:

Raw Events
value 1 value 2 value 3, widths [8,8,8]
value 1value 2value 3, widths [7,7,7]
ParameterTypeRequiredDefault ValueDescription
columnsarray of stringsrequired   Names of columns to extract from field.
field[a]stringoptional[b] @rawstring Field that holds the input in fixed width form.
trimbooleanoptional[b] true Remove leading and trailing white-space from fields after extracting.
widthsarray of numbersrequired   Widths of columns.

[a] The parameter name field can be omitted.

[b] Optional parameters use their default value unless explicitly set.

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For a log line like this:

ini
2017-02-22T13:14:01.917+0000 [main thread] INFO statsModule got result="117success 27% 3.14"

Using parseFixedWidth(result, columns=[count, status, completion, precision, sourcetask], widths=[3,9,4,10,10) will add these fields:

accesslog
count: 117
status: success
completion: 27%
precision: 3.14

Sourcetask will not get assigned a value, as there were too few columns in the input for that. Values are trimmed after they have been extracted, for example, success will become success from the above example.

Use the (unnamed) field parameter to specify which field should be parsed. Specify @rawstring to parse the raw string

parseFixedWidth() Syntax Examples

Fixed width parse the result field from a log line:

accesslog
statsModule got result="117success 27% 3.14

The query:

logscale
parseFixedWidth(result, columns=[count, status,completion, precision, sourcetask], widths=[3,9,4,10,10])

will add the following fields to the event:

  • count=117

  • status=success

  • completion=27%

  • precision=3.14

sourcetask will not get set as the input is too short.

Click + next to an example below to get the full details.

Parse Fixed Width-encoded Log Lines Fields

Parse fixed width-encoded field from log lines into columns using the parseFixedWidth() function

Query
logscale
parseFixedWidth(result, columns=[count, status, completion, precision, sourcetask], widths=[3,9,4,10,10])
Introduction

A fixed width file can be a very compact representation of numeric data. The file type is fast to parse, because every field is in the same place in every line. A disadvantages of fixed width file is, that it is necessary to describe the length of every field being parsed.

In this example, the parseFixedWidth() function is used to parse an accesslog.

Step-by-Step

  1. Starting with the source repository events.

  2. logscale
    parseFixedWidth(result, columns=[count, status, completion, precision, sourcetask], widths=[3,9,4,10,10])

    Parses the fixed width-encoded field in the accesslog and adds the returned values as known columns in the result field.

  3. Event Result set.

Summary and Results

The query is used to parse compact numeric data consisting of fixed width-encoded fields into columns.

In case a field value is longer than, for example, 10 characters, the parser handles overflow by truncating data that exceeds the specified field width while maintaining the structure of the parsed output.

As an example, if the original sourcetask value was: SCAN_FILES_WITH_VERY_LONG_NAME (29 characters), then the extra characters _WITH_VERY_LONG_NAME would be truncated.

This parsing method is particularly valuable when dealing with structured data that must maintain strict positional formatting and character length requirements.