LogPattern 
    An object that defines the log patterns that belongs to a LogPatternSet.
Types
Properties
The name of the log pattern. A log pattern name can contain as many as 50 characters, and it cannot be empty. The characters can be Unicode letters, digits, or one of the following symbols: period, dash, underscore.
The name of the log pattern. A log pattern name can contain as many as 30 characters, and it cannot be empty. The characters can be Unicode letters, digits, or one of the following symbols: period, dash, underscore.
Rank of the log pattern. Must be a value between 1 and 1,000,000. The patterns are sorted by rank, so we recommend that you set your highest priority patterns with the lowest rank. A pattern of rank 1 will be the first to get matched to a log line. A pattern of rank 1,000,000 will be last to get matched. When you configure custom log patterns from the console, a Low severity pattern translates to a 750,000 rank. A Medium severity pattern translates to a 500,000 rank. And a High severity pattern translates to a 250,000 rank. Rank values less than 1 or greater than 1,000,000 are reserved for Amazon Web Services provided patterns.