String Functions in Calculated Fields

# Usage: CONCAT(arg1, arg2, ...)
# Examples
CONCAT($api_version, $sdk)
IF($is_batch, CONCAT($url, "-batch"), $url)

# Usage: TO_LOWER(string)`
# Examples
TO_LOWER($service.name)
IF(CONTAINS(TO_LOWER(app.user.name), "bob"), "bob!", "not bob!")

# Usage: STARTS_WITH(string, prefix)
# Examples
STARTS_WITH($url, "https")
STARTS_WITH($user_agent, "ELB-")

# Usage: ENDS_WITH(string, suffix)
# Examples
ENDS_WITH($filename, ".json")

# Usage: CONTAINS(string, substr)`
# Examples
CONTAINS($email, "@honeycomb.io")
CONTAINS($header_accept_encoding, "gzip")
IF(CONTAINS($url, "/v1/"), "api_v1", "api_v2")

# Usage: REG_MATCH(string, regex)
# Examples
REG_MATCH($error_msg, `^[a-z]+\[[0-9]+\]$`)
REG_MATCH($referrer, `[\w-_]+\.(s3\.)?amazonaws.com`)

# Usage: REG_VALUE(string, regex)
# Examples
REG_VALUE($user_agent, `Chrome/[\d.]+`)
REG_VALUE($source, `^(ui-\d+|log|app-\d+)`)

IF(CONTAINS($user_agent, "honeytail"), REG_VALUE($user_agent, `\([a-z]+\)`), null)

# Usage: REG_COUNT(string, regex)
# Examples
REG_COUNT($sql, `JOIN`)
REG_COUNT($ip, `19.`)

# Usage: LENGTH(string[, "bytes" | "chars"])
# Examples
LENGTH($hostname, "bytes")      # returns the number of bytes that make up the string.
LENGTH($hostname, "chars")      # returns the number of user-perceived characters that make up the string.

LENGTH("🏳️‍🌈", "bytes")      # == 14
LENGTH("🏳️‍🌈", "chars")      # == 1