Log Service provides the domain-specific language (DSL) to construct expression functions that return specific values to help you transform log data.
The following table lists expression functions.
Type | Function | Description |
---|---|---|
Event check functions | Functions such as v, e_has, e_not_has, e_search, e_match, e_match_any, and e_match_all | Returns the values of fields, or checks whether a field or the value of a field meets specified conditions. |
Operator functions | op_* functions | Compares values, performs condition-based or container-based judgment, or performs general multi-value calculation. |
Conversion functions | ct_* functions | Converts data types among numeric values, strings, and Boolean values, or converts numbers between different numeral systems. |
Arithmetic functions | op_*, math_*, and mat_* functions | Performs mathematical calculation or multi-value calculation. |
String functions | st_* functions | Processes strings. |
Date and time functions | dt_* functions | Converts time data among UNIX timestamps, datetime objects, and date and time strings, changes time zones, and returns the difference between two time values. |
Regular expression functions | regex_* functions | Extracts, returns, replaces, or splits values based on regular expressions. |
Grok function | Grok function | Extracts specific values based on regular expressions. |
Structured data functions | json_*, xml_*, and pb_* functions | Extracts or parses fields. |
Encoding and decoding functions | url_*, html_*, md5_*, sha1_*, and base64_* functions | Encodes or decodes data. |
Parsing functions | ua_* functions | Parses the User-Agent HTTP header. |
List functions | op_* and lst_* functions | Constructs, returns, or modifies a list. |
Dictionary functions | op_* and dct_* functions | Constructs, returns, or modifies a dictionary. |
Table functions | tab_* functions | Constructs a table from a text file or constructs a dictionary from a table. |
Resource functions | res_* functions | Obtains the values of the advanced parameters of a data transformation task. Pulls data from an Object Storage Service (OSS) bucket, Logstores, or a table in an ApsaraDB RDS for MySQL database. |