This topic describes the syntax and parameters of string functions. This topic also provides examples on how to use the functions.

Functions

Category Function Description
Multi-string operation str_format Formats strings.
str_join Concatenates input values by using a specified connector to generate a new string.
str_zip Concurrently splits two values or strings that are returned by expressions and combines the results to a string.
Encoding and decoding str_encode Encodes a string by using a specified encoding format.
str_decode Decodes an input value by using a specified encoding format.
str_hex_escape_encode Escapes special characters. The function can escape hexadecimal characters to Chinese characters.
str_uuid Generates a random UUID.
Sorting, reversing, and replacement str_sort Sorts a specified object.
str_reverse Reverses a string.
str_replace Replaces an old string with a new string based on a specified rule.
str_logstash_config_normalize Converts data in the Logstash configuration language to the JSON format.
str_translate Replaces specified characters in a string with mapping characters.
Regular munging str_strip Deletes specified characters from a string.
str_lstrip Deletes specified characters from the start of a string.
str_rstrip Deletes specified characters from the end of a string.
str_lower Converts all uppercase letters in a string to lowercase letters.
str_upper Converts all lowercase letters in a string to uppercase letters.
str_title Capitalizes the first letter of each word in a string and converts the other letters in the string to lowercase letters.
str_capitalize Capitalizes the first letter of a string and converts the other letters in the string to lowercase letters.
str_swapcase Interchanges the uppercase letters and lowercase letters in a string.
Search and check str_count Counts the number of occurrences of a character in a string.
str_find Checks whether a string contains a specified substring.
str_rfind Returns the position of the last occurrence of a specified character in a string.
str_endswith Checks whether a string ends with a specified suffix.
str_startswith Checks whether a string starts with a specified string.
Splitting str_split Splits a string by using a specified delimiter.
str_splitlines Splits a string by using a line feed.
str_partition Splits a string into three parts from left to right by using a specified delimiter.
str_rpartition Splits a string into three parts from right to left by using a specified delimiter.
Formatting str_center Pads a string to a specified length by using a specified character.
str_ljust Pads a string to a specified length by using a specified character from the end of the string.
str_rjust Pads a string to a specified length by using a specified character from the start of the string.
str_zfill Pads a string to a specified length by using 0 from the start of the string.
str_expandtabs Converts \t in a string to spaces.
Character set check str_isalnum Checks whether a string contains only letters and digits.
str_isalpha Checks whether a string contains only letters.
str_isascii Checks whether a string is in the ASCII table.
str_isdecimal Checks whether a string contains only decimal characters.
str_isdigit Checks whether a string contains only digits.
str_isidentifier Checks whether a string is a valid Python identifier or checks whether a variable name is valid.
str_islower Checks whether a string contains lowercase letters.
str_isnumeric Checks whether a string contains digits.
str_isprintable Checks whether all characters in a string are printable characters.
str_isspace Checks whether a string contains only spaces.
str_istitle Checks whether the first letter of each word in a string is in uppercase and the other letters in the string are in lowercase.
str_isupper Checks whether all letters in a string are in uppercase.
The following table describes the functions that can be used together with string functions.
Category Function Description
Multi-string operation op_add Returns the sum value among multiple numeric values or strings.
op_max Returns the maximum value among multiple numeric values or strings.
op_min Returns the minimum value among multiple numeric values or strings.
String truncation op_slice Truncates a string.
Length calculation op_len Returns the length of a string.

str_format

  • Syntax
    str_format(formatting string, value 1, value 2, ...)
  • Parameters
    Parameter Type Required Description
    formatting string Arbitrary (automatically converted to the string type) Yes The format of the output string. Example: {}={}.
    value 1 Arbitrary Yes The value that you want to format.
    value 2 Arbitrary Yes The value that you want to format.
  • Response

    A formatted string is returned.

  • Examples
    Raw log:
    class: Format
    escape_name: Traditional
    Transformation rule:
    e_set("str_format", str_format("{}={}",v("class"),v("escape_name")))
    Result:
    class: Format
    escape_name: Traditional
    str_format: Format=Traditional

str_join

  • Syntax
    str_join(connector, value 1, value 2, ...)
  • Parameters
    Parameter Type Required Description
    connector Arbitrary (automatically converted to the string type) Yes The connector. Supported connectors include the exclamation point (!), at sign (@), number sign (#), dollar sign ($), and percent sign (%).
    value 1 Arbitrary (automatically converted to the string type) Yes The value that you want to concatenate.
    value 2 Arbitrary (automatically converted to the string type) Yes The value that you want to concatenate.
  • Response

    A concatenated string is returned.

  • Examples
    Raw log:
    name: ETL
    company: aliyun.com
    Transformation rule:
    e_set("email", str_join("@",v("name"),v("company")))
    Result:
    name: ETL
    company: aliyun.com
    email:ETL@aliyun.com

str_encode

  • Syntax
    str_encode(value, "utf8", errors="ignore"))
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The value that you want to encode.
    encoding String No The encoding format. Default value: utf8. ASCII is supported.
    errors String No The method that is used to process characters if the characters cannot be recognized based on the encoding format. Valid values:
    • ignore: The characters are not encoded. This is the default value.
    • strict: An error is reported, and the data of the log is discarded.
    • replace: The characters are replaced with question marks (?).
    • xmlcharrefreplace: The characters are replaced with the related XML characters.
  • Response

    An encoded string is returned.

  • Examples
    • Example 1
      Raw log:
      test: asewds
      Transformation rule:
      e_set("f1", str_decode(str_encode("hello", "utf8"), "utf8"))
      Result:
      test: asewds
      f1: hello
    • Example 2
      Raw log:
      f2: test test data
      Transformation rule:
      e_set("f1", str_encode(v("f2"), "ascii", errors="ignore"))
      Result:
      f1:test 
      f2:test test data
    • Example 3
      Raw log:
      f2: test test data
      Transformation rule:
      e_set("f1", str_encode(v("f2"), "ascii", errors="strict"))
      Result:
      An error is reported during execution. 
    • Example 4
      Raw log:
      f2: test test data
      Transformation rule:
      e_set("f1", str_encode(v("f2"), "ascii", errors="replace"))
      Result:
      f1:test ????
      f2:test test data
    • Example 5
      Raw log:
      f2: test test data
      Transformation rule:
      e_set("f1", str_encode(v("f2"), "ascii", errors="xmlcharrefreplace"))
      Result:
      f1:test 测试数据
      f2:test test data

str_decode

  • Syntax
    str_decode(value, "utf8", errors="ignore"))
    Note The str_decode function can process only the data of the byte data type.
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The value that you want to decode.
    encoding Arbitrary (automatically converted to the string type) No The encoding format. Default value: utf8. ASCII is supported.
    errors Arbitrary (automatically converted to the string type) No The method that is used to process characters if the characters cannot be recognized based on the encoding format. Valid values:
    • ignore: The characters are not encoded. This is the default value.
    • strict: An error is reported, and the data of the log is discarded.
    • replace: The characters are replaced with question marks (?).
    • xmlcharrefreplace: The characters are replaced with the related XML characters.
  • Response

    A decoded value is returned.

  • Examples
    Raw log:
    test: asewds
    Transformation rule:
    e_set("encoding", str_decode(b'\xe4\xbd\xa0\xe5\xa5\xbd', "utf8",'strict'))
    Result:
    test: asewds
    encoding: hello

str_replace

  • Syntax
    str_replace(value, old, new, count)
    Note You can call this function by passing basic variable parameters. For more information, see Function invoking.
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The value in which you want to replace a string.
    old Arbitrary (automatically converted to the string type) Yes The string that you want to replace.
    new Arbitrary (automatically converted to the string type) Yes The string that you want to use to replace the specified string.
    count Number No The number of replacements. If you do not configure this parameter, the specified string in all occurrences in the value is replaced.
  • Response

    A new string is returned.

  • Examples: Convert a dictionary to the JSON format.
    Raw log:
    content:  {'referer': '-', 'request': 'GET /phpMyAdmin', 'status': 404, 'data-1': {'aaa': 'Mozilla', 'bbb': 'asde'}, 'data-2': {'up_adde': '-', 'up_host': '-'}}
    Transformation rule:
    e_set("content_json", str_replace(ct_str(v("content")),"'",'"'))
    Result:
    content:  {'referer': '-', 'request': 'GET /phpMyAdmin', 'status': 404, 'data-1': {'aaa': 'Mozilla', 'bbb': 'asde'}, 'data-2': {'up_adde': '-', 'up_host': '-'}}
    content_json:  {"referer": "-", "request": "GET /phpMyAdmin", "status": 404, "data-1": {"aaa": "Mozilla", "bbb": "asde"}, "data-2": {"up_adde": "-", "up_host": "-"}}

str_sort

  • Syntax
    str_sort(value, reverse)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to sort.
    reverse Boolean No Default value: False. This value indicates that the string is sorted in ascending order.
  • Response

    A sorted string is returned.

  • Examples
    • Example 1: Sort the str field value in alphabetical order.
      Raw log:
      str: twish
      Transformation rule:
      e_set("str_sort", str_sort(v("str")))
      Result:
      str: twish
      str_sort: histw
    • Example 2: Sort the str field value in reverse alphabetical order at a granularity of two-letter pairs.
      Raw log:
      str: twish
      Transformation rule:
      e_set("str_sort", str_sort(v("str"),True))
      Result:
      str: twish
      str_sort: wtsih

str_reverse

  • Syntax
    str_reverse(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The value that you want to reverse.
  • Response

    A reversed string is returned.

  • Examples: Reverse the data field value.
    Raw log:
    data:twish
    Transformation rule:
    e_set("reverse_data", str_reverse(v("data")))
    Result:
    data:twish
    reverse_data:hsiwt

str_logstash_config_normalize

  • Syntax
    str_logstash_config_normalize(value)
    Note For more information about the Logstash configuration language, see Logstash.
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The value that you want to convert.
  • Response

    A converted string is returned.

  • Examples: Convert the logstash field value.
    Raw log:
    logstash: {"name"=>"tw5"}
    Transformation rule:
    e_set("normalize_data", str_logstash_config_normalize(v("logstash")))
    Result:
    logstash: {"name"=>"tw5"}
    normalize_data:{"name":"tw5"}

str_hex_escape_encode

  • Syntax
    str_hex_escape_encode(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The value that you want to escape.
  • Response

    An escaped string is returned.

str_strip

  • Syntax
    str_strip(value, chars)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to modify.
    chars Arbitrary (automatically converted to the string type) No The character set that you want to delete from the start and end of the specified string. Default value: \t\r\n.
  • Response

    A modified string is returned.

  • Examples
    • Example 1: Delete the asterisks (*) from the start of the strip field value.
      Raw log
      strip: ***I love Etl
      Transformation rule
      e_set("str_strip", str_strip(v("strip"),"*"))
      Result
      strip: ***I love Etl
      str_strip:I love Etl
    • Example 2: Delete the spaces from the start of the strip field value.
      Raw log
      strip:    I love Etl
      Transformation rule
      e_set("str_strip", str_strip(v("strip")))
      Result
      strip:    I love Etl
      str_strip: I love Etl
    • Example 3: Delete the character set xy.
      Raw log
      strip:xy123yx
      Transformation rule
      e_set("str_strip", str_strip(v("strip"),"xy"))
      Result
      strip:xy123yx
      str_strip:123

str_lower

  • Syntax
    str_lower(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to convert.
  • Response

    A converted string is returned.

  • Examples: Convert the name field value to lowercase letters.
    Raw log:
    name: Etl
    Transformation rule:
    e_set("str_lower", str_lower(v("name")))
    Result:
    name: Etl
    str_lower: etl

str_upper

  • Syntax
    str_upper(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to convert.
  • Response

    A converted string is returned.

  • Examples: Convert the name field value to uppercase letters.
    Raw log:
    name: etl
    Transformation rule:
    e_set("str_upper", str_upper(v("name")))
    Result:
    name: etl
    str_upper: ETL

str_title

  • Syntax
    str_title(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to convert.
  • Response

    A converted string is returned.

  • Examples: Capitalize the first letter of each word in the word field value.
    Raw log:
    word: this is etl
    Transformation rule:
    e_set("str_title", str_title(v("word")))
    Result:
    word: this is etl
    str_title: This Is Etl

str_capitalize

  • Syntax
    str_capitalize(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to convert.
  • Response

    A converted string is returned.

  • Examples: Capitalize the first letter of the word field value and convert the other letters in the value to lowercase letters.
    Raw log:
    word: this Is MY EAL
    Transformation rule:
    e_set("str_capitalize", str_capitalize(v("word")))
    Result:
    word: this Is MY EAL
    str_capitalize: This is my eal

str_lstrip

  • Syntax
    str_lstrip(value, chars)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to modify.
    chars Arbitrary (automatically converted to the string type) No The character set that you want to delete from the start of the string. Default value: space.
  • Response

    A modified string is returned.

  • Examples
    • Example 1: Delete the asterisks (*) from the start of the word field value.
      Raw log:
      word: ***this is string
      Transformation rule:
      e_set("str_lstrip", str_lstrip(v("word"),"*"))
      Result:
      word: ***this is string
      str_lstrip: this is string
    • Example 2: Delete the spaces from the start of the word field value.
      Raw log:
      word:     this is string
      Transformation rule:
      e_set("str_lstrip", str_lstrip(v("word")))
      Result:
      word:     this is string
      str_lstrip: this is string
    • Example 3: Delete the character set xy.
      Raw log:
      lstrip:xy123yx
      Transformation rule:
      e_set("str_lstrip", str_lstrip(v("lstrip"),"xy"))
      Result:
      lstrip:xy123yx
      str_lstrip:123yx

str_rstrip

  • Syntax
    str_rstrip(value, chars)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to modify.
    chars Arbitrary (automatically converted to the string type) No The character set that you want to delete from the end of the string. Default value: space.
  • Response

    A modified string is returned.

  • Examples
    • Example 1: Delete the asterisks (*) from the end of the word field value.
      Raw log:
      word: this is string*****
      Transformation rule:
      e_set("str_rstrip", str_rstrip(v("word"),"*"))
      Result:
      word: this is string*****
      str_rstrip: this is string
    • Example 2: Delete the character set xy.
      Raw log:
      word:xy123yx
      Transformation rule:
      e_set("str_rstrip", str_rstrip(v("word"),"xy"))
      Result:
      word:xy123yx
      str_rstrip:xy123

str_swapcase

  • Syntax
    str_swapcase(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to convert.
  • Response

    A converted string is returned.

  • Examples
    Raw log:
    name: this is string
    Transformation rule:
    e_set("str_swapcase", str_swapcase(v("name")))
    Result:
    name: this is string
    str_swapcase: THIS IS STRING

str_translate

  • Syntax
    str_translate(value, original character set, mapping character set)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string in which you want to replace characters.
    original character set Arbitrary (automatically converted to the string type) Yes The original character set.
    mapping character set Arbitrary (automatically converted to the string type) Yes The character set that is used to replace characters in the original character set.
  • Response

    A processed string is returned.

  • Examples
    Raw log:
    name: I love ETL!!!
    Transformation rule:
    e_set("str_translate", str_translate(v("name"),"aeiou","12345"))
    Result:
    name: I love ETL!!!
    str_translate: I l4v2 ETL!!!

str_endswith

  • Syntax
    str_endswith(value, suffix, start, end)
    Note You can call this function by passing basic variable parameters. For more information, see Function invoking.
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to check.
    suffix Arbitrary (automatically converted to the string type) Yes The suffix. The value of this parameter can be a string or an element.
    start Number No The position from which the string suffix check starts.

    The value 0 indicates the first character. The value -1 indicates the last character.

    end Number No The position at which the string suffix check ends.

    The value 0 indicates the first character. The value -1 indicates the last character.

  • Response

    If the string ends with the specified suffix, the value True is returned. Otherwise, the value False is returned.

  • Examples
    Raw log:
    name: this is endswith!!!
    Transformation rule:
    e_set("str_endswith",str_endswith(v("name"),"!"))
    Result:
    name: this is endswith!!!
    str_endswith: True

str_startswith

  • Syntax
    str_startswith(value, prefix, start, end)
    Note You can call this function by passing basic variable parameters. For more information, see Function invoking.
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to check.
    prefix Arbitrary (automatically converted to the string type) Yes The prefix. The value of this parameter can be a string or an element.
    start Number No The position from which the string prefix check starts.

    The value 0 indicates the first character. The value -1 indicates the last character.

    end Number No The position at which the string prefix check ends.

    The value 0 indicates the first character. The value -1 indicates the last character.

  • Response

    If the string starts with the specified prefix, the value True is returned. Otherwise, the value False is returned.

  • Examples
    Raw log:
    name: !! this is startwith
    Transformation rule:
    e_set("str_startswith",str_startswith(v("name"),"!!"))
    Result:
    name: !! this is startwith
    str_startswith: True

str_find

  • Syntax
    str_find(value, str, begin, end)
    Note You can call this function by passing basic variable parameters. For more information, see Function invoking.
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string in which you want to search for a substring.
    str Arbitrary (automatically converted to the string type) Yes The substring that you want to search for.
    begin Number No The position from which the substring search starts.

    Default value: 0. The value 0 indicates the first character. The value -1 indicates the last character.

    end Number No The position at which the substring search ends.

    The default value is the length of the string. The value 0 indicates the first character. The value -1 indicates the last character.

  • Response

    The position of the specified substring in the original string is returned. If the specified substring appears multiple times in the original string, only the position of the first occurrence of the substring is returned.

  • Examples
    Raw log:
    name: hello world
    Transformation rule:
    e_set("str_find",str_find(v("name"),"h"))
    Result:
    name: hello world
    str_find: 0

str_count

  • Syntax
    str_count(value, sub, start, end)
    Note You can call this function by passing basic variable parameters. For more information, see Function invoking.
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string in which you want to count the number of occurrences of a character.
    sub Arbitrary (automatically converted to the string type) Yes The character whose number of occurrences you want to count.
    start Number No The position from which the search for the specified character starts in the string. Valid values:
    • 0: the first character. This is the default value.
    • -1: the last character.
    end Number No The position at which the search for the specified character ends in the string. Valid values:
    • 0: the first character.
    • -1: the last character. This is the default value.
  • Response

    The number of occurrences of the specified character is returned.

  • Examples
    Raw log:
    name: this is really a string
    Transformation rule:
    e_set("str_count",str_count(v("name"),"i"))
    Result:
    name: this is really a string
    str_count: 3

str_rfind

  • Syntax
    str_rfind(value, substr, beg, end)
    Note You can call this function by passing basic variable parameters. For more information, see Function invoking.
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string in which you want to search for a character.
    substr Arbitrary (automatically converted to the string type) Yes The character that you want to search for.
    beg Number No The position from which the search starts. Default value: 0.
    end Number No The position at which the search ends. The default value is the length of the string.
  • Response

    The position of the last occurrence of the specified character is returned.

  • Examples
    Raw log:
    name: this is really a string
    Transformation rule:
    e_set("str_rfind",str_rfind(v("name"),"i"))
    Result:
    name: this is really a string
    str_rfind: 20

str_split

  • Syntax
    str_split(value, sep=None, maxsplit=-1)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to split.
    sep Number No The delimiter. The value None indicates a space.
    maxsplit Number No The maximum number of strings into which you can split the original string. The value -1 indicates no limit.
  • Response

    A processed string is returned.

  • Examples: Split the content field value by using the space delimiter.
    Raw log:
    content: hello world
    Transformation rule:
    e_set("str_split",str_split(v("content")," "))
    Result:
    content: hello world
    str_split: ["hello", "world"]

str_splitlines

  • Syntax
    str_splitlines(value, keepends)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to split.
    keepends Boolean No Specifies whether to delete line feeds from the output result. The line feeds include \r, \r\n, and \n. Default value: False. This value indicates that line feeds are deleted. The value True indicates that line feeds are retained.
  • Response

    Processed strings are returned.

  • Examples
    • Example 1
      Raw log:
      content: ab c\n\nde fg\rkl\r\n
      Transformation rule:
      e_set("str_splitlines",str_splitlines(v("content"),False))
      Result:
      content: ab c\n\nde fg\rkl\r\n
      str_splitlines: ['ab c', '', 'de fg', 'kl']
    • Example 2
      Raw log:
      content: ab c\n\nde fg\rkl\r\n
      Transformation rule:
      e_set("str_splitlines",str_splitlines(v("content"),True))
      Result:
      content: ab c\n\nde fg\rkl\r\n  
      str_splitlines: ['ab c\n', '\n', 'de fg\r', 'kl\r\n']

str_partition

  • Syntax
    str_partition(value, substr)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to split.
    substr Arbitrary (automatically converted to the string type) No The delimiter.
  • Response

    Split strings are returned.

  • Examples: Split the website field value into three parts from left to right by using the . delimiter.
    Raw log:
    website: www.aliyun.com
    Transformation rule:
    e_set("str_partition",str_partition(v("website"),"."))
    Result:
    website: www.aliyun.com
    str_partition:  ["www", ".", "aliyun.com"]

str_rpartition

  • Syntax
    str_rpartition(value, substr)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to split.
    substr Arbitrary (automatically converted to the string type) No The delimiter.
  • Response

    Processed strings are returned.

  • Examples: Split the website field value into three parts from right to left by using the . delimiter.
    Raw log:
    website: www.aliyun.com
    Transformation rule:
    e_set("str_partition",str_rpartition(v("website"),"."))
    Result:
      website: www.aliyun.com
      str_partition: ["www.aliyun", ".", "com"]

str_center

  • Syntax
    str_center(value, width, fillchar)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to modify.
    width Number Yes The length of the string after padding.
    fillchar Arbitrary (automatically converted to the string type) No The character that is used for padding. Default value: space.
  • Response
    A processed string is returned.
    Note If the length of the string after padding is less than the length of the original string, the original string is returned.
  • Examples
    • Example 1: Pad a string by using asterisks (*).
      Raw log:
      center: this is center
      Transformation rule:
      e_set("str_center", str_center(v("center"), 40, "*"))
      Result:
      center: this is center
      str_center: *************this is center*************
    • Example 2: Pad a string by using spaces.
      Raw log:
      center: this is center
      Transformation rule:
      e_set("str_center",str_center(v("center"),40))
      Result:
      center: this is center
      str_center:              this is center 

str_zfill

  • Syntax
    str_zfill(value, width)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to modify.
    width Number Yes The length of the string after padding.
  • Response

    A processed string is returned.

  • Examples
    Raw log:
    center: this is zfill
    Transformation rule:
    e_set("str_zfill",str_zfill(v("center"),40))
    Result:
    center:this is zfill
    str_zfill:000000000000000000000000000this is zfill

str_expandtabs

  • Syntax
    str_expandtabs(value, tabsize)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to modify.
    tabsize Number Yes The number of spaces after conversion.
  • Response

    A processed string is returned.

  • Examples
    • Example 1: Convert \t in the logstash field value to a space.
      Raw log:
      logstash: this is\tstring
      Transformation rule:
      e_set("str_expandtabs",str_expandtabs(v("logstash")))
      Result:
      logstash: this is\tstring
      str_expandtabs: this is string
    • Example 2: Convert \t in the center field value to spaces.
      Raw log:
      {"center": "this is\tstring"}
      Transformation rule:
      e_set("str_expandtabs",str_expandtabs(v("center"),16))
      Result:
      center: this is\tstring
      str_expandtabs: this is         string

str_ljust

  • Syntax
    str_ljust(value, width, fillchar)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to modify.
    width Number Yes The length of the string after padding.
    fillchar Arbitrary (automatically converted to the string type) No The character that is used for padding. Default value: space.
  • Response
    A processed string is returned.
    Note If the length of the string after padding is less than the length of the original string, the original string is returned.
  • Examples
    • Example 1
      Raw log:
      content: this is ljust
      Transformation rule:
      e_set("str_ljust",str_ljust(v("content"),20,"*"))
      Result:
      content: this is ljust
      str_ljust: this is ljust*******
    • Example 2
      Raw log:
      center: this is ljust
      Transformation rule:
      e_set("str_ljust",str_ljust(v("center"),20,))
      Result:
      center: this is ljust
      str_ljust: this is ljust   
    • Example 3: The value of width is less than the length of the original string. The original string is returned.
      Raw log:
      center: this is ljust
      Transformation rule:
      e_set("str_ljust",str_ljust(v("center"),10,"*"))
      Result:
      center: this is ljust
      str_ljust: this is ljust

str_rjust

  • Syntax
    str_rjust(value, width, fillchar)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The original string that you want to modify.
    width Number Yes The length of the string after padding.
    fillchar Arbitrary (automatically converted to the string type) No The character that is used for padding. Default value: space.
  • Response
    A processed string is returned.
    Note If the length of the string after padding is less than the length of the original string, the original string is returned.
  • Examples
    Raw log:
    center: this is rjust
    Transformation rule:
    e_set("str_rjust",str_rjust(v("center"),20,"*"))
    Result:
    center: this is rjust
    str_rjust: *******this is rjust

str_zip

  • Syntax
    str_zip(value 1, value 2, combine_sep=None, sep=None, quote=None, lparse=None, rparse=None)
  • Parameters
    Parameter Type Required Description
    value 1 Arbitrary (automatically converted to the string type) Yes The value that you want to combine.
    value 2 Arbitrary (automatically converted to the string type) Yes The value that you want to combine.
    combine_sep Arbitrary (automatically converted to the string type) No The identifier that is used when elements are combined. Default value: #.
    sep Arbitrary (automatically converted to the string type) No The delimiter that is used between the elements after combining. The value must be a single character. Default value: ,.
    quote Arbitrary (automatically converted to the string type) No The character is used to enclose the elements after combining. This parameter is required if the values contain delimiters. Default value: ".
    lparse Arbitrary (automatically converted to the string type) No The delimiter and quote that are used among the elements of value 1. Default delimiter: ,. Default quote: ". Format: lparse=(',', '"').
    Note The quote has a higher priority than the delimiter.
    rparse Arbitrary (automatically converted to the string type) No The delimiter and quote that are used among the elements of value 2. Default delimiter ,. Default quote: ". Format: rparse=(',', '"').
    Note The quote has a higher priority than the delimiter.
  • Response

    A combined string is returned.

  • Examples
    • Example 1
      Raw log:
      website: wwww.aliyun.com
      escape_name: o
      Transformation rule:
      e_set("combine",str_zip(v("website"),v("escape_name"), combine_sep="@"))
      Result:
      website: wwww.aliyun.com
      escape_name: o
      combine: wwww.aliyun.com@o
    • Example 2
      Raw log:
      website: wwww.aliyun.com
      escape_name: o
      Transformation rule:
      e_set("combine",str_zip(v("website"),v("escape_name")))
      Result:
      website: wwww.aliyun.com
      escape_name: o
      wwww.aliyun.com#o  
    • Example 3: In this example, the sep parameter is used.
      Raw log:
      f1: a,b,c
      f2: x,y,z
      Transformation rule:
      e_set("combine",str_zip(v("f1"), v("f2"), sep="|"))
      Result:
      f1: a,b,c
      f2: x,y,z
      combine: a#x|b#y|c#z
    • Example 4: In this example, the quote parameter is used.
      Raw log:
      f1: "a,a", b, "c,c"
      f2: x, "y,y", z
      Transformation rule:
      e_set("combine",str_zip(v("f1"), v("f2"), quote='|'))
      Result:
      f1: "a,a", b, "c,c"
      f2: x, "y,y", z
      combine: |a,a#x|,|b#y,y|,|c,c#z|
    • Example 5: In this example, field values with different lengths are used.
      Raw log:
      f1: a,b
      f2: x,y,z
      Transformation rule:
      e_set("combine",str_zip(v("f1"), v("f2")))
      Result:
      f1: a,b
      f2: x,y,z
      combine: a#x,b#y
    • Example 6: In this example, the lparse and rparse parameters are used.
      Raw log:
      f1: a#b#c
      f2: x|y|z
      Transformation rule:
      e_set("combine",str_zip(v("f1"), v("f2"), lparse=("#", '"'), rparse=("|", '"')))
      Result:
      f1: a#b#c
      f2: x|y|z
      combine: a#x,b#y,c#z
    • Example 7: In this example, the lparse and rparse parameters are used.
      Raw log:
      f1: |a,a|, b, |c,c|
      f2: x, #y,y#, z
      Transformation rule:
      e_set("combine",str_zip(v("f1"), v("f2"), lparse=(",", '|'), rparse=(",", '#')))
      Result:
      f1: |a,a|, b, |c,c|
      f2: x, #y,y#, z
      combine: "a,a#x","b#y,y","c,c#z"

str_isalnum

  • Syntax
    str_isalnum(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    content: 13
    Transformation rule:
    e_set("str_isalnum",str_isalnum(v("content")))
    Result:
    content: 13
    str_isalnum: True

str_isalpha

  • Syntax
    str_isalpha(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    content: 13
    Transformation rule:
    e_set("str_isalpha",str_isalpha(v("content")))
    Result:
    content: 13
    str_isalpha: False

str_isascii

  • Syntax
    str_isascii(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    content: asw123
    Transformation rule:
    e_set("str_isascii",str_isascii(v("content")))
    Result:
    content: asw123
    str_isascii: True

str_isdecimal

  • Syntax
    str_isdecimal(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    • Example 1
      Raw log:
      welcome: hello
      Transformation rule:
      e_set("str_isdecimal",str_isdecimal(v("welcome")))
      Result:
      welcome: hello
      str_isdecimal: False
    • Example 2
      Raw log:
      num: 123
      Transformation rule:
      e_set("str_isdecimal",str_isdecimal(v("num")))
      Result:
      num: 123
      str_isdecimal: True

str_isdigit

  • Syntax
    str_isdigit(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    content: 13
    Transformation rule:
    e_set("str_isdigit",str_isdigit(v("content")))
    Result:
    content: 13
    str_isdigit: True

str_isidentifier

  • Syntax
    str_isidentifier(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    class: class
    Transformation rule:
    e_set("str_isidentifier",str_isidentifier(v("class")))
    Result:
    class: class
    str_isidentifier: True

str_islower

  • Syntax
    str_islower(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    lower: asds
    Transformation rule:
    e_set("str_islower",str_islower(v("lower")))
    Result:
    lower: asds
    str_islower: True

str_isnumeric

  • Syntax
    str_isnumeric(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    num: 123
    Transformation rule:
    e_set("str_isnumeric",str_isnumeric(v("num")))
    Result:
    num: 123
    str_isnumeric: True

str_isprintable

  • Syntax
    str_isprintable(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    content: vs;,.as
    Transformation rule:
    e_set("str_isprintable",str_isprintable(v("content")))
    Result:
    content: vs;,.as
    str_isprintable: True

str_isspace

  • Syntax
    str_isspace(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    space:  as afsd
    Transformation rule:
    e_set("str_isspace",str_isspace(v("space")))
    Result:
    space:  as afsd
    str_isspace: False

str_istitle

  • Syntax
    str_istitle(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    title: Alex
    Transformation rule:
    e_set("str_istitle",str_istitle(v("title")))
    Result:
    title: Alex
    str_istitle: True

str_isupper

  • Syntax
    str_isupper(value)
  • Parameters
    Parameter Type Required Description
    value Arbitrary (automatically converted to the string type) Yes The string that you want to check.
  • Response

    The value True or False is returned.

  • Examples
    Raw log:
    content: ASSD
    Transformation rule:
    e_set("str_isupper",str_isupper(v("content")))
    Result:
    content: ASSD
    str_isupper: True

str_uuid

  • Syntax
    str_uuid(lower=True)
  • Parameters
    Parameter Type Required Description
    lower Boolean No Specifies whether the letters in the output UUID are in lowercase. Default value: True. This value indicates that the letters are in lowercase.
  • Response

    A UUID is returned.

  • Examples
    • Example 1
      Raw log:
      content: I am Iron man
      Transformation rule:
      e_set("UUID",str_uuid())
      Result:
      content: I am Iron man
      UUID: dcc54d7e-c95f-11e9-9791-ffd6754a4f32
    • Example 2
      Raw log:
      content: I am Iron man
      Transformation rule:
      e_set("UUID",str_uuid(lower=False))
      Result:
      content: I am Iron man
      UUID: DCC72D74-C95F-11E9-9921-F395B8647FFA