Contents

• Getting Started
• Usage
  • File Functions
  • String Functions
  • Math Functions
  • Container Functions
  • Parser Functions
  • Advanced Functions
• Contributing
• Support
• License
• Legal

Getting Started

Download the latest binary from the Release page. Make it executable with chmod +x goplater and run it for the first time.

Use the goplater template command to template files:

./goplater template TEMPLATE.md -o README.md

This will create a new file called README.md in your current working directory.

Usage

Format

Goplater uses Go's builtin templating library therefor the syntax should be consistent with other projects.

Example:

File Content: +​{​{​{ read "./myfile.txt" }​}​}

File Functions

As you saw in the example above read is used for reading and output file contents. But there are more as you will see in the following…

read

Reads from absolute or relative file path (depending on input), where relative paths are relative to the invoker.

read "path"

readArgs

Same as [read], but allows to supply additional arguments to the file for further processing.

read "path" arg1 arg2 arg3

Arguments are accessible in under .args with {{{ index .args 0 }}}.

fetch

Performs a get http request to the specified url.

fetch "url"

String Functions

trim

Outputs trimmed string.

upper

Outputs uppercased string.

lower

Outputs lowercased string.

contains

Returns wether string contains substring.

contains "Sunflower" "flower"

count

Returns amount of times that substring is present in string.

repeat

Repeats string n times.

repeat "*" 5

startsWith

Returns wether string starts with prefix.

startsWith "Sunflower" "Sun"

endsWith

Returns wether string ends with prefix.

endsWith "Sunflower" "flower"

isEmpty

Returns wether string is empty ("").

indexOf

Returns starting index of substring in string.

indexOf "Apple Banana Strawberry" "Apple"

replace

Replaces substring with new string in old string.

replace "Sunflower" "flower" "shine"

split

Split string by separator and return slice of all parts.

split "Apple, Banana, Strawberry" ", "

before

Outputs string before substring in string.

before "Apple Banana Strawberry" "Banana"

after

Outputs string after substring in string.

after "Apple Banana Strawberry" "Apple"

between

Outputs inbetween of starting and ending substring.

between "Apple Banana Strawberry" "Apple" "Strawberry"

slice

Slice string by start and end bounds.

slice "  Apple  " 2 7

join

Joins strings with separator.

join "Apple" "Banana" "Strawberry" ", "

concat

Concat multiple strings.

concat "Apple" "Banana" "Strawberry"

append

Appends another string to string.

append "Hello " "World!"

regexMatch

Outputs wether string matches regex.

regexMatch "[0-9]" "0123456789"

regexFind

Returns a list of all regex matches.

index ( regexFind "[1-36-9]" "01234 56789" ) 0

regexFindGroups

Returns a nested list ([][]string) of all regex submatches (groups (.*)).

index ( index ( regexFindGroups "(_*)(\S+)(_*)" "__xyz__" 0 ) 0 )

regexReplace

Replaces substring via regex in string.

regexReplace "string" "replace_regex" "replace_with"

Math Functions

add

Adds two numbers together.

sub

Subtraction for two numbers.

mult

Multiplies two numbers.

divd

Divides a through b.

mod

Performs a modulo b.

Conversion Functions

Functions for converting types.

toString

Returns value as string (via fmt.Sprint()).

toInt

Parses string as int.

toFloat64

Parses string as float64.

toFloat32

Same as toFloat64, but for float32.

toBool

Parses string as bool.

Container Functions

The following are functions for slices and maps.

has

Returns wether map or slice has key.

includes

Returns wether map or slice includes value.

delete

Deletes an entry from a map or slice.

delete map "key"

delete slice 0

set

Returns map or slice with updated key.

set map "key" value

set slice 0 value

mapCreate

Creates empty map (map[string]any).

mapCreateWith

Creates map by using arguments as key value pairs.

mapCreateWith "key1" value1 "key2" value2

slicePush

Returns slice with value pushed on top.

slicePush slice value

sliceCreate

Creates empty slice.

sliceCreateWith

Creates slice by using arguments as items.

sliceCreate "a" "b" "c"

Parser Functions

The following section is dedicated to parser functions, for example json.

jsonDecode

Parses json string as map.

jsonEncode

Returns json string from object.

yamlDecode

Parses yaml string as map.

yamlEncode

Returns yaml string from object.

base64Decode

Decodes base64 into raw string.

base64Encode

Encodes raw string into base64.

htmlDecode

Parses html string as html document.

htmlDocFind

Query element by selector in html document.

htmlDocFind ( html "html_string" ) "h3:contains['xyz']"

htmlFind

Query element by selector within another element.

htmlFind ( htmlDocFind document ) "h3:contains['xyz']"

htmlText

Outputs inner text of a html element.

htmlText ( htmlDocFind document "selector" )

htmlAttr

Outputs the value of the specified elements attribute.

htmlAttr ( htmlDocFind document "selector" ) "attribute"

htmlInner

Outputs element's inner html string.

htmlInner ( htmlDocFind document "selector" )

Advanced Functions

In addition to the function in the Simple Functions section, there are also some functions for advanced usage.

import

Imports a file and executes it as template, output is discarded.

import "functions.inc.gtmpl"

globalSet

Sets key globally to value.

globalSet "key" value

globalGet

Returns global value at key.

funcDefine

Defines a global function.

funcDefine "name" `
    {{{ return 0 "Hello World" }}}
`

The second argument is the template body, notice the {{{ ... }}} instead of $​{​{​{ ... }​}​}.

Raw output is discarded only output via return persists.

return

[!WARNING] This function is only accessible from within functions!

Sets return argument at index to value.

funcDefine "helloWorld" "{{{ return 0 "Hello World!" }}}"

Overwriting previous return arguments is possible.

returnNext

Same as return, but appends to output.

Shorthand for:

return i+1 value

returnNext value

returnAll

Sets return output slice directly with multiple arguments.

returnAll out1 out2 out3

returnOutputs

Sets return output slice directly with one slice.

returnOutputs slice

getOutputs

Returns the whole output slice.

funcCall

Calls a global function by its name (without passing any arguments).

funcCall "name"

Returns list of return outputs in order of index, or if applicable only a single output.

funcCallArgs

Same as funcCall, but arguments can be passed.

funcCallArgs "name" arg1 arg2

Arguments are accessible in function body with {{{ index .args 0 }}}.

Contributing

Found a bug or just want to change or add something? Feel free to open up an issue or a PR!

Support

Like this Project? Or just want to help? Why not ⭐️ this Repo? :)

License

This Project is licensed under the MIT License.

Legal

Logo designed by @CodeShellDev — All Rights Reserved. Go gopher mascot originally created by Renée French, used under the CC BY 4.0 license.