String functions - Simple Log Service - Alibaba Cloud Documentation Center

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 in a specified format.
	str_join	Concatenates input strings 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 into one 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 existing string with a new string based on a specified rule.
	str_logstash_config_normalize	Converts the data in the Logstash configuration language to the JSON format.
	str_translate	Replaces specified characters in a string with new characters based on a mapping relationship.
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	Converts the uppercase letters in a string to lowercase letters and lowercase letters to uppercase letters.
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	Queries the position of the last occurrence of a specified string or character in an input string.
	str_endswith	Checks whether a string ends with a specified suffix.
	str_startswith	Checks whether a string starts with a specified prefix.
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	Right pads a string to a specified length by using a specified character.
	str_rjust	Left pads a string to a specified length by using a specified character.
	str_zfill	Left pads a string to a specified length by using 0.
	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 only lowercase letters.
	str_isnumeric	Checks whether all characters in a string are numeric.
	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 of 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

The str_format function formats strings in a specified format.

Syntax

str_format(format_string, value1, value2, ...)

Parameters

Parameter	Type	Required	Description
format_string	Arbitrary (automatically converted to the string type)	Yes	The format of the output string. Example: `{}={}`.
value1	Arbitrary	Yes	The value that you want to format.
value2	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

The str_join function concatenates input strings by using a specified connector to generate a new string.

Syntax

str_join(connector, value1,  value2, ....)

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 (%).
value1	Arbitrary (automatically converted to the string type)	Yes	The value that you want to concatenate.
value2	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

The str_encode function encodes a string by using a specified encoding format.

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: UTF-8. 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 (default): The characters are not encoded. strict: An error is reported, and the log is discarded. replace: The unrecognizable characters are replaced with question marks (?). xmlcharrefreplace: The unrecognizable characters are replaced with 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 &#27979;&#35797;&#25968;&#25454;
f2:test Test data

str_decode

The str_decode function decodes an input value by using a specified encoding format.

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: UTF-8. 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 (default): The characters are not decoded. strict: An error is reported, and the log is discarded. replace: The unrecognizable characters are replaced with question marks (?). xmlcharrefreplace: The unrecognizable characters are replaced with 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

The str_replace function replaces an existing string with a new string based on a specified rule.

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 after the replacement.
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

The str_sort function sorts a specified object.

Syntax
```
str_sort(value, reverse=False)
```

Parameters

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

Response
A sorted string is returned.
Examples
- Example 1: Sort the value of the str field 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 value of the str field 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"), reverse=True))
```
  - Result
```
str: twish
str_sort: wtsih
```

str_reverse

The str_reverse function reverses a string.

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 value of the data field.

Raw log
```
data:twish
```

Transformation rule

e_set("reverse_data", str_reverse(v("data")))

Result
```
data:twish
reverse_data:hsiwt
```

str_logstash_config_normalize

The str_logstash_config_normalize function converts the data in the Logstash configuration language to the JSON format.

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 value of the field in Logstash.

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

The str_hex_escape_encode function escapes special characters. The function can escape hexadecimal characters to Chinese characters.

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.

Examples

Escape the value of the myfriend field to Chinese characters.

Raw log
```
myfriend: \xE6\x9F\xB3\xE4\xBA\x91
```

Transformation rule

e_set("hex_myfriend", str_hex_escape_encode("myfriend"))

Result

hex_myfriend:myfriend
myfriend:\xE6\x9F\xB3\xE4\xBA\x91

str_strip

The str_strip function deletes specified characters from a string.

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 new 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 xy character set.

Raw log
```
strip:xy123yx
```

Transformation rule

e_set("str_strip", str_strip(v("strip"), "xy"))

Result
```
strip:xy123yx
str_strip:123
```

str_lower

The str_lower function converts all uppercase letters in a string to lowercase letters.

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 value of the name field 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

The str_upper function converts all lowercase letters in a string to uppercase letters.

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 value of the name field 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

The str_title function capitalizes the first letter of each word in a string and converts the other letters in the string to lowercase letters.

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 value of the word field.
- 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

The str_capitalize function capitalizes the first letter of a string and converts the other letters in the string to lowercase letters.

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

The str_lstrip function deletes specified characters from the start of a string.

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 new 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 xy character set.

Raw log
```
lstrip:xy123yx
```

Transformation rule

e_set("str_lstrip", str_lstrip(v("lstrip"),"xy"))

Result
```
lstrip:xy123yx
str_lstrip:123yx
```

str_rstrip

The str_rstrip function deletes specified characters from the end of a string.

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 new 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 xy character set.

Raw log
```
word:xy123yx
```

Transformation rule

e_set("str_rstrip", str_rstrip(v("word"), "xy"))

Result
```
word:xy123yx
str_rstrip:xy123
```

str_swapcase

The str_swapcase function converts the uppercase letters in a string to lowercase letters and lowercase letters to uppercase letters.

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

The str_translate function replaces specified characters in a string with new characters based on a mapping relationship.

Syntax

str_translate(value, replace_string, mapping_string)

Parameters

Parameter	Type	Required	Description
value	Arbitrary (automatically converted to the string type)	Yes	The original string in which you want to replace characters.
replace_string	Arbitrary (automatically converted to the string type)	Yes	The character set that you want to replace.
mapping_string	Arbitrary (automatically converted to the string type)	Yes	The character set after the replacement.

Response
A new 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

The str_endswith function checks whether a string ends with a specified suffix.

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 check starts. The value 0 specifies the first character. The value -1 specifies the last character.
end	Number	No	The position at which the check ends. The value 0 specifies the first character. The value -1 specifies 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

The str_startswith function checks whether a string starts with a specified prefix.

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 check starts. The value 0 specifies the first character. The value -1 specifies the last character.
end	Number	No	The position at which the check ends. The value 0 specifies the first character. The value -1 specifies 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

The str_find function checks whether a string contains a specified substring.

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 search starts. The default value 0 specifies the first character. The value -1 specifies the last character.
end	Number	No	The position at which the search ends. The default value is the length of the string. The value 0 specifies the first character. The value -1 specifies 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

The str_count function counts the number of occurrences of a character in a string.

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 (default): the first character -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 (default): the last character

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

The str_rfind function queries the position of the last occurrence of a specified string or character in an input string.

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 specified 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 or string 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

The str_split function splits a string by using a specified delimiter.

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 specifies a space.
maxsplit	Number	No	The maximum number of substrings into which you can split the string. The value -1 specifies no limit.

Response
Processed strings are returned.

Examples

Split the value of the content field 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

The str_splitlines function splits a string by using a line feed.

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 retain line feeds in the result. The line feeds include `\r`, `\r\n`, and `\n`. Default value: False, which specifies that line feeds are deleted. The value True specifies 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

The str_partition function splits a string into three parts from left to right by using a specified delimiter.

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
Processed 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

The str_rpartition function splits a string into three parts from right to left by using a specified delimiter.

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

The str_center function pads a string to a specified length by using a specified character.

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 new string is returned.
Note
If the length of the new 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 the 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

The str_zfill function left pads a string to a specified length by using 0.

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 new 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

The str_expandtabs function converts \t in a string to spaces.

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 the conversion.
Response
A new string is returned.

Examples

Example 1: Convert \t in the logstash field value to spaces.

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

The str_ljust function right pads a string to a specified length by using a specified character.

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 new string is returned.
Note
If the length of the new 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: Return the original string because the length of the new string after padding is less than the length of the original string.
- 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

The str_rjust function left pads a string to a specified length by using a specified character.

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 new string is returned.
Note
If the length of the new 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

The str_zip function concurrently splits two values or strings that are returned by expressions and combines the results into one string.

Syntax

str_zip(value1, value2, combine_sep=None, sep=None, quote=None, lparse=None, rparse=None)

Parameters

Parameter	Type	Required	Description
value1	Arbitrary (automatically converted to the string type)	Yes	The value that you want to combine.
value2	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 to combine the elements. 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 that 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 `value1`. 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 `value2`. 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

combine:wwww.aliyun.com#o  
escape_name:o
website:wwww.aliyun.com

Example 3: Use the sep parameter.

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: Use the quote parameter.

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: Use field values whose lengths are different.

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: Use the lparse and rparse parameters.

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: Use the lparse and rparse parameters.

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

The str_isalnum function checks whether a string contains only letters and digits.

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

The str_isalpha function checks whether a string contains only letters.

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

The str_isascii function checks whether a string is in the ASCII table.

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

The str_isdecimal function checks whether a string contains only decimal characters.

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

The str_isdigit function checks whether a string contains only digits.

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

The str_isidentifier function checks whether a string is a valid Python identifier or checks whether a variable name is valid.

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

The str_islower function checks whether a string contains only lowercase letters.

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

The str_isnumeric function checks whether all characters in a string are numeric.

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

The str_isprintable function checks whether all characters in a string are printable characters.

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

The str_isspace function checks whether a string contains only spaces.

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

The str_istitle function checks whether the first letter of each word in a string is in uppercase and the other letters in the string are in lowercase.

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 Is A Boy
```

Transformation rule

e_set("str_istitle", str_istitle(v("title")))

Result
```
str_istitle:true
title:Alex Is A Boy
```

str_isupper

The str_isupper function checks whether all letters in a string are in uppercase.

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

The str_uuid function generates a random 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, which specifies 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: e9fcd6b0-b970-11ec-979d-0f7041e65ab8

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: 0649211E-B971-11EC-A258-E71F0A2930C5

Functions

str_format

Syntax

Parameters

Response

Examples

str_join

Syntax

Parameters

Response

Examples

str_encode

Syntax

Parameters

Response

Examples

str_decode

Syntax

Parameters

Response

Examples

str_replace

Syntax

Parameters

Response

Examples

str_sort

Syntax

Parameters

Response

Examples

str_reverse

Syntax

Parameters

Response

Examples

str_logstash_config_normalize

Syntax

Parameters

Response

Examples

str_hex_escape_encode

Syntax

Parameters

Response

Examples

str_strip

Syntax

Parameters

Response

Examples

str_lower

Syntax

Parameters

Response

Examples

str_upper

Syntax

Parameters

Response

Examples

str_title

Syntax

Parameters

Response

Examples

str_capitalize

Syntax

Parameters

Response

Examples

str_lstrip

Syntax

Parameters

Response

Examples

str_rstrip

Syntax

Parameters

Response