Add the sprig functions in the template engine

vendor/github.com/Masterminds/sprig/doc.go

@@ -0,0 +1,225 @@
+/*
+Sprig: Template functions for Go.
+
+This package contains a number of utility functions for working with data
+inside of Go `html/template` and `text/template` files.
+
+To add these functions, use the `template.Funcs()` method:
+
+	t := templates.New("foo").Funcs(sprig.FuncMap())
+
+Note that you should add the function map before you parse any template files.
+
+	In several cases, Sprig reverses the order of arguments from the way they
+	appear in the standard library. This is to make it easier to pipe
+	arguments into functions.
+
+Date Functions
+
+	- date FORMAT TIME: Format a date, where a date is an integer type or a time.Time type, and
+	  format is a time.Format formatting string.
+	- dateModify: Given a date, modify it with a duration: `date_modify "-1.5h" now`. If the duration doesn't
+	  parse, it returns the time unaltered. See `time.ParseDuration` for info on duration strings.
+	- now: Current time.Time, for feeding into date-related functions.
+	- htmlDate TIME: Format a date for use in the value field of an HTML "date" form element.
+	- dateInZone FORMAT TIME TZ: Like date, but takes three arguments: format, timestamp,
+	  timezone.
+	- htmlDateInZone TIME TZ: Like htmlDate, but takes two arguments: timestamp,
+	  timezone.
+
+String Functions
+
+	- abbrev: Truncate a string with ellipses. `abbrev 5 "hello world"` yields "he..."
+	- abbrevboth: Abbreviate from both sides, yielding "...lo wo..."
+	- trunc: Truncate a string (no suffix). `trunc 5 "Hello World"` yields "hello".
+	- trim: strings.TrimSpace
+	- trimAll: strings.Trim, but with the argument order reversed `trimAll "$" "$5.00"` or `"$5.00 | trimAll "$"`
+	- trimSuffix: strings.TrimSuffix, but with the argument order reversed: `trimSuffix "-" "ends-with-"`
+	- trimPrefix: strings.TrimPrefix, but with the argument order reversed `trimPrefix "$" "$5"`
+	- upper: strings.ToUpper
+	- lower: strings.ToLower
+	- nospace: Remove all space characters from a string. `nospace "h e l l o"` becomes "hello"
+	- title: strings.Title
+	- untitle: Remove title casing
+	- repeat: strings.Repeat, but with the arguments switched: `repeat count str`. (This simplifies common pipelines)
+	- substr: Given string, start, and length, return a substr.
+	- initials: Given a multi-word string, return the initials. `initials "Matt Butcher"` returns "MB"
+	- randAlphaNum: Given a length, generate a random alphanumeric sequence
+	- randAlpha: Given a length, generate an alphabetic string
+	- randAscii: Given a length, generate a random ASCII string (symbols included)
+	- randNumeric: Given a length, generate a string of digits.
+	- wrap: Force a line wrap at the given width. `wrap 80 "imagine a longer string"`
+	- wrapWith: Wrap a line at the given length, but using 'sep' instead of a newline. `wrapWith 50, "<br>", $html`
+	- contains: strings.Contains, but with the arguments switched: `contains substr str`. (This simplifies common pipelines)
+	- hasPrefix: strings.hasPrefix, but with the arguments switched
+	- hasSuffix: strings.hasSuffix, but with the arguments switched
+	- quote: Wrap string(s) in double quotation marks, escape the contents by adding '\' before '"'.
+	- squote: Wrap string(s) in double quotation marks, does not escape content.
+	- cat: Concatenate strings, separating them by spaces. `cat $a $b $c`.
+	- indent: Indent a string using space characters. `indent 4 "foo\nbar"` produces "    foo\n    bar"
+	- replace: Replace an old with a new in a string: `$name | replace " " "-"`
+	- plural: Choose singular or plural based on length: `len $fish | plural "one anchovy" "many anchovies"`
+	- sha256sum: Generate a hex encoded sha256 hash of the input
+	- toString: Convert something to a string
+
+String Slice Functions:
+
+	- join: strings.Join, but as `join SEP SLICE`
+	- split: strings.Split, but as `split SEP STRING`. The results are returned
+	  as a map with the indexes set to _N, where N is an integer starting from 0.
+	  Use it like this: `{{$v := "foo/bar/baz" | split "/"}}{{$v._0}}` (Prints `foo`)
+	- splitList: strings.Split, but as `split SEP STRING`. The results are returned
+	  as an array.
+	- toStrings: convert a list to a list of strings. 'list 1 2 3 | toStrings' produces '["1" "2" "3"]'
+	- sortAlpha: sort a list lexicographically.
+
+Integer Slice Functions:
+
+	- until: Given an integer, returns a slice of counting integers from 0 to one
+	  less than the given integer: `range $i, $e := until 5`
+	- untilStep: Given start, stop, and step, return an integer slice starting at
+	  'start', stopping at `stop`, and incrementing by 'step. This is the same
+	  as Python's long-form of 'range'.
+
+Conversions:
+
+	- atoi: Convert a string to an integer. 0 if the integer could not be parsed.
+	- in64: Convert a string or another numeric type to an int64.
+	- int: Convert a string or another numeric type to an int.
+	- float64: Convert a string or another numeric type to a float64.
+
+Defaults:
+
+	- default: Give a default value. Used like this: trim "   "| default "empty".
+	  Since trim produces an empty string, the default value is returned. For
+	  things with a length (strings, slices, maps), len(0) will trigger the default.
+	  For numbers, the value 0 will trigger the default. For booleans, false will
+	  trigger the default. For structs, the default is never returned (there is
+	  no clear empty condition). For everything else, nil value triggers a default.
+	- empty: Return true if the given value is the zero value for its type.
+	  Caveats: structs are always non-empty. This should match the behavior of
+	  {{if pipeline}}, but can be used inside of a pipeline.
+	- coalesce: Given a list of items, return the first non-empty one.
+	  This follows the same rules as 'empty'. '{{ coalesce .someVal 0 "hello" }}`
+	  will return `.someVal` if set, or else return "hello". The 0 is skipped
+	  because it is an empty value.
+	- compact: Return a copy of a list with all of the empty values removed.
+	  'list 0 1 2 "" | compact' will return '[1 2]'
+
+OS:
+	- env: Resolve an environment variable
+	- expandenv: Expand a string through the environment
+
+File Paths:
+	- base: Return the last element of a path. https://golang.org/pkg/path#Base
+	- dir: Remove the last element of a path. https://golang.org/pkg/path#Dir
+	- clean: Clean a path to the shortest equivalent name.  (e.g. remove "foo/.."
+	  from "foo/../bar.html") https://golang.org/pkg/path#Clean
+	- ext: https://golang.org/pkg/path#Ext
+	- isAbs: https://golang.org/pkg/path#IsAbs
+
+Encoding:
+	- b64enc: Base 64 encode a string.
+	- b64dec: Base 64 decode a string.
+
+Reflection:
+
+	- typeOf: Takes an interface and returns a string representation of the type.
+	  For pointers, this will return a type prefixed with an asterisk(`*`). So
+	  a pointer to type `Foo` will be `*Foo`.
+	- typeIs: Compares an interface with a string name, and returns true if they match.
+	  Note that a pointer will not match a reference. For example `*Foo` will not
+	  match `Foo`.
+	- typeIsLike: Compares an interface with a string name and returns true if
+	  the interface is that `name` or that `*name`. In other words, if the given
+	  value matches the given type or is a pointer to the given type, this returns
+	  true.
+	- kindOf: Takes an interface and returns a string representation of its kind.
+	- kindIs: Returns true if the given string matches the kind of the given interface.
+
+	Note: None of these can test whether or not something implements a given
+	interface, since doing so would require compiling the interface in ahead of
+	time.
+
+Data Structures:
+
+	- tuple: Takes an arbitrary list of items and returns a slice of items. Its
+	  tuple-ish properties are mainly gained through the template idiom, and not
+	  through an API provided here. WARNING: The implementation of tuple will
+	  change in the future.
+	- list: An arbitrary ordered list of items. (This is prefered over tuple.)
+	- dict: Takes a list of name/values and returns a map[string]interface{}.
+	  The first parameter is converted to a string and stored as a key, the
+	  second parameter is treated as the value. And so on, with odds as keys and
+	  evens as values. If the function call ends with an odd, the last key will
+	  be assigned the empty string. Non-string keys are converted to strings as
+	  follows: []byte are converted, fmt.Stringers will have String() called.
+	  errors will have Error() called. All others will be passed through
+	  fmt.Sprtinf("%v").
+
+Lists Functions:
+
+These are used to manipulate lists: '{{ list 1 2 3 | reverse | first }}'
+
+	- first: Get the first item in a 'list'. 'list 1 2 3 | first' prints '1'
+	- last: Get the last item in a 'list': 'list 1 2 3 | last ' prints '3'
+	- rest: Get all but the first item in a list: 'list 1 2 3 | rest' returns '[2 3]'
+	- initial: Get all but the last item in a list: 'list 1 2 3 | initial' returns '[1 2]'
+	- append: Add an item to the end of a list: 'append $list 4' adds '4' to the end of '$list'
+	- prepend: Add an item to the beginning of a list: 'prepend $list 4' puts 4 at the beginning of the list.
+	- reverse: Reverse the items in a list.
+	- uniq: Remove duplicates from a list.
+	- without: Return a list with the given values removed: 'without (list 1 2 3) 1' would return '[2 3]'
+	- has: Return 'true' if the item is found in the list: 'has "foo" $list' will return 'true' if the list contains "foo"
+
+Dict Functions:
+
+These are used to manipulate dicts.
+
+	- set: Takes a dict, a key, and a value, and sets that key/value pair in
+	  the dict. `set $dict $key $value`. For convenience, it returns the dict,
+	  even though the dict was modified in place.
+	- unset: Takes a dict and a key, and deletes that key/value pair from the
+	  dict. `unset $dict $key`. This returns the dict for convenience.
+	- hasKey: Takes a dict and a key, and returns boolean true if the key is in
+	  the dict.
+	- pluck: Given a key and one or more maps, get all of the values for that key.
+	- keys: Get an array of all of the keys in a dict.
+	- pick: Select just the given keys out of the dict, and return a new dict.
+	- omit: Return a dict without the given keys.
+
+Math Functions:
+
+Integer functions will convert integers of any width to `int64`. If a
+string is passed in, functions will attempt to convert with
+`strconv.ParseInt(s, 1064)`. If this fails, the value will be treated as 0.
+
+	- add1: Increment an integer by 1
+	- add: Sum an arbitrary number of integers
+	- sub: Subtract the second integer from the first
+	- div: Divide the first integer by the second
+	- mod: Module of first integer divided by second
+	- mul: Multiply integers
+	- max: Return the biggest of a series of one or more integers
+	- min: Return the smallest of a series of one or more integers
+	- biggest: DEPRECATED. Return the biggest of a series of one or more integers
+
+Crypto Functions:
+
+	- genPrivateKey: Generate a private key for the given cryptosystem. If no
+	  argument is supplied, by default it will generate a private key using
+	  the RSA algorithm. Accepted values are `rsa`, `dsa`, and `ecdsa`.
+	- derivePassword: Derive a password from the given parameters according to the ["Master Password" algorithm](http://masterpasswordapp.com/algorithm.html)
+	  Given parameters (in order) are:
+          `counter` (starting with 1), `password_type` (maximum, long, medium, short, basic, or pin), `password`,
+           `user`, and `site`
+
+SemVer Functions:
+
+These functions provide version parsing and comparisons for SemVer 2 version
+strings.
+
+	- semver: Parse a semantic version and return a Version object.
+	- semverCompare: Compare a SemVer range to a particular version.
+*/
+package sprig