renderer

Documentation

Overview

Package renderer implements data-driven templates for generating textual output

The renderer extends the standard golang text/template and sprig functions.

Templates are executed by applying them to a data structure (configuration). Values in the template refer to elements of the data structure (typically a field of a struct or a key in a map).

Actions can be combined using UNIX-like pipelines.

The input text for a template is UTF-8-encoded text in any format.

See renderer.ExtraFunctions for our custom functions.

Detailed documentation on the syntax and available functions can be found here:

• https://golang.org/pkg/text/template
• http://masterminds.github.io/sprig
• https://godoc.org/github.com/reefbarman/render/renderer#Renderer.ExtraFunctions

Index

• Constants
• func Gzip(input interface{}) (string, error)
• func ToYaml(marshallable interface{}) (string, error)
• func Ungzip(input interface{}) (string, error)
• type Renderer
  • func New(configuration configuration.Configuration, opts ...string) *Renderer
  • func (r *Renderer) Delim(left, right string) *Renderer
  • func (r *Renderer) Execute(t *template.Template) (string, error)
  • func (r *Renderer) ExtraFunctions() template.FuncMap
  • func (r *Renderer) FileRender(inputPath, outputPath string) error
  • func (r *Renderer) Parse(templateName, rawTemplate string, extraFunctions template.FuncMap) (*template.Template, error)
  • func (r *Renderer) ReadFile(file string) (string, error)
  • func (r *Renderer) Render(templateName, rawTemplate string) (string, error)
  • func (r *Renderer) SimpleRender(rawTemplate string) (string, error)
  • func (r *Renderer) Validate() error

Constants

const (
	// MissingKeyInvalidOption is the renderer option to continue execution on missing key and print "<no value>"
	MissingKeyInvalidOption = "missingkey=invalid"
	// MissingKeyErrorOption is the renderer option to stops execution immediately with an error on missing key
	MissingKeyErrorOption = "missingkey=error"
	// LeftDelim is the default left template delimiter
	LeftDelim = "{{"
	// RightDelim is the default right template delimiter
	RightDelim = "}}"
)

Functions

func Gzip

func Gzip(input interface{}) (string, error)

Gzip compresses the input using gzip algorithm

func ToYaml

func ToYaml(marshallable interface{}) (string, error)

ToYaml is a template function, it turns a marshallable structure into a YAML fragment

func Ungzip

func Ungzip(input interface{}) (string, error)

Ungzip un-compresses the input using gzip algorithm

Types

type Renderer

type Renderer struct {
	// contains filtered or unexported fields
}

Renderer structure holds configuration and options

func New

func New(configuration configuration.Configuration, opts ...string) *Renderer

New creates a new renderer with the specified configuration and zero or more options

func (*Renderer) Delim

func (r *Renderer) Delim(left, right string) *Renderer

Delim mutates Renderer with new left and right delimiters

func (*Renderer) Execute

func (r *Renderer) Execute(t *template.Template) (string, error)

Execute is a basic template execution function

func (*Renderer) ExtraFunctions

func (r *Renderer) ExtraFunctions() template.FuncMap

ExtraFunctions provides additional template functions to the standard (text/template) ones, it adds sprig functions and custom functions:

• render - calls the render from inside of the template, making the renderer recursive
• readFile - reads a file from a given path, relative paths are translated to absolute paths, based on root function
• root - the root path for rendering, used relative to absolute path translation in any file based operations
• toYaml - provides a configuration data structure fragment as a YAML format
• gzip - use gzip compression inside the templates, for best results use with b64enc
• ungzip - use gzip extraction inside the templates, for best results use with b64dec

func (*Renderer) FileRender

func (r *Renderer) FileRender(inputPath, outputPath string) error

FileRender is used to render files by path, see also Render

func (*Renderer) Parse

func (r *Renderer) Parse(templateName, rawTemplate string, extraFunctions template.FuncMap) (*template.Template, error)

Parse is a basic template parsing function

func (*Renderer) ReadFile

func (r *Renderer) ReadFile(file string) (string, error)

ReadFile is a template function that allows for an in-template file opening

func (*Renderer) Render

func (r *Renderer) Render(templateName, rawTemplate string) (string, error)

Render is the main rendering function, see also SimpleRender, Configuration and ExtraFunctions

func (*Renderer) SimpleRender

func (r *Renderer) SimpleRender(rawTemplate string) (string, error)

SimpleRender is a simple rendering function, also used as a custom template function to allow in-template recursive rendering, see also Render, RenderWith

func (*Renderer) Validate

func (r *Renderer) Validate() error

Validate checks the internal state and returns error if necessary