Strings (str)

Description

The string vmod implements various helper function to manipulate strings.

API

len

INT len(STRING S)

Returns the number of ascii characters in S, or -1 if S is null.

Arguments:

S accepts type STRING

Type: Function

Returns: Int

startswith

BOOL startswith(STRING S1, STRING S2)

Returns true if S1 starts with S2.

Arguments:

S1 accepts type STRING
S2 accepts type STRING

Type: Function

Returns: Bool

endswith

BOOL endswith(STRING S1, STRING S2)

Returns true if S1 ends with S2.

Arguments:

S1 accepts type STRING
S2 accepts type STRING

Type: Function

Returns: Bool

contains

BOOL contains(STRING S1, STRING S2)

Returns true if S1 contains S2.

Arguments:

S1 accepts type STRING
S2 accepts type STRING

Type: Function

Returns: Bool

substr

STRING substr(STRING S, INT N, INT OFFSET = 0)

Returns a substring that is at most abs(N) characters long, from the character at the OFFSET position (negative OFFSET counts from the back of the string). If N is positive, the substring is extracted right of OFFSET, left otherwise.

Example:

substr(“0123456789abcdef”, 2, 5) -> “56”, 2 characters from the 5th one
substr(“0123456789abcdef”, 2, -5) -> “be”, 2 characters from the 5th to last one
substr(“0123456789abcdef”, -2, 5) -> “45”, 2 characters to the 5th one
substr(“0123456789abcdef”, -2, -5) -> “ab”, 2 characters to the 5th to last one
substr(“0123456789abcdef”, 10, 20) -> “abcdef”, truncated because the end of the string was reached.

If S in NULL, NULL is returned.

Arguments:

S accepts type STRING
N accepts type INT
OFFSET accepts type INT with a default value of 0 optional

Type: Function

Returns: String

reverse

STRING reverse(STRING S)

Reverse S.

Arguments:

S accepts type STRING

Type: Function

Returns: String

split

STRING split(STRING S, INT n, STRING SEP = " \t")

Split s and return the N-th token (index starts at 1). Characters in SEP are separators. A negative N indicate “from the end of the string”. The value of “STRING SEP” can be multiple characters, the vmod will split the string at all of the given values.

Example:

split("/item_1.mp4|/item_2.mp4|/item_3/mp4", 1, “|”) -> “/item_1.mp4”, first item, | as a separator.
split("/item_1.mp4|/item_2.mp4|/item_3/mp4", -1, “|@”) -> “/item_3.mp4”, last item, | or @ as a separator.
split("/item_1.mp4@/item_2.mp4@/item_3/mp4", 2, “@”) -> “/item_2.mp4”, second item, @ as a seperator.
split("/item_1.mp4|/item_2.mp4@/item_3/mp4", -1, “|@”) -> “/item_3/mp4”, last item, @ or | as a separator.

Arguments:

S accepts type STRING
n accepts type INT
SEP accepts type STRING with a default value of \t optional

Type: Function

Returns: String

token_intersect

BOOL token_intersect(STRING str1, STRING str2, [STRING separators])

Checks if the set tokens in one string intersects the set of tokens in the other string. In other words, it returns true if there is a token which exists in both strings.

If the separators argument is not supplied, the space and comma characters are the separators. Empty tokens are ignored in both strings.

Arguments:

str1 accepts type STRING
str2 accepts type STRING
separators accepts type STRING

Type: Function

Returns: Bool

Availability

The str VMOD is available in Varnish Enterprise version 6.0.4r3 and later.