README
¶
jujusvg
A library for generating SVGs from Juju bundles and environments.
Installation
To start using jujusvg, first ensure you have a valid Go environment, then run the following:
go get gopkg.in/juju/jujusvg.v1
Dependencies
The project uses godeps (https://launchpad.net/godeps) to manage Go dependencies. To install this, run:
go get launchpad.net/godeps
After installing it, you can update the dependencies to the revision specified
in the dependencies.tsv file with the following:
make deps
Use make create-deps to update the dependencies file.
Usage
Given a Juju bundle, you can convert this to an SVG programatically. This generates a simple SVG representation of a bundle or bundles that can then be included in a webpage as a visualization.
For an example of how to use this library, please see examples/generatesvg.go.
You can run this example like:
go run generatesvg.go bundle.yaml > bundle.svg
The examples directory also includes three sample bundles that you can play around with, or you can use the Juju GUI to generate your own bundles.
Design-related assets
Some assets are specified based on assets provided by the design team. These assets are specified in the defs section of the generated SVG, and can thus be found in the Canvas.definition() method. These assets are, except where indicated, embedded in a go file assigned to an exported variable, so that they may be used like so:
import (
"io"
"gopkg.in/juju/jujusvg.v1/assets"
)
// ...
io.WriteString(canvas.Writer, assets.AssetToWrite)
Current assets in use:
- The service block
The relation health indicatorthis is defined by hand, but a similar path may be taken in the future if the asset should change
Documentation
¶
Overview ¶
jujusvg generates SVG representations of various Juju artifacts, such as charm bundles or live environments.
For more information, please refer to the README file in this directory.
Index ¶
Constants ¶
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Variables ¶
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Functions ¶
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Types ¶
type Canvas ¶
type Canvas struct {
// contains filtered or unexported fields
}
Canvas holds the parsed form of a bundle or environment.
func NewFromBundle ¶
func NewFromBundle(b *charm.BundleData, iconURL func(*charm.Reference) string, fetcher IconFetcher) (*Canvas, error)
NewFromBundle returns a new Canvas that can be used to generate a graphical representation of the given bundle data. The iconURL function is used to generate a URL that refers to an SVG for the supplied charm URL. If fetcher is non-nil, it will be used to fetch icon contents for any icons embedded within the charm, allowing the generated bundle to be self-contained. If fetcher is nil, a default fetcher which refers to icons by their URLs as svg <image> tags will be used.
type HTTPFetcher ¶
type HTTPFetcher struct {
// Concurrency specifies the number of GoRoutines to use when fetching
// icons. If it is not positive, 10 will be used. Setting this to 1
// makes this method nominally synchronous.
Concurrency int
// IconURL returns the URL from which to fetch the given entity's icon SVG.
IconURL func(*charm.Reference) string
// Client specifies what HTTP client to use; if it is not provided,
// http.DefaultClient will be used.
Client *http.Client
}
HTTPFetcher is an implementation of IconFetcher which retrieves charm icons from the web using the URL generated by IconURL on that charm. The HTTP Client used may be overridden by an instance of http.Client. The icons may optionally be fetched concurrently.
func (*HTTPFetcher) FetchIcons ¶
func (h *HTTPFetcher) FetchIcons(b *charm.BundleData) (map[string][]byte, error)
FetchIcons retrieves icon SVGs over HTTP. If specified in the struct, icons will be fetched concurrently.
type IconFetcher ¶
An IconFetcher provides functionality for retrieving icons for the charms within a given bundle. The FetchIcons function accepts a bundle, and returns a map from charm paths to icon data.
type LinkFetcher ¶
type LinkFetcher struct {
// IconURL returns the URL of the entity for embedding
IconURL func(*charm.Reference) string
}
LinkFetcher fetches icons as links so that they are included within the SVG as remote resources using SVG <image> tags.
func (*LinkFetcher) FetchIcons ¶
func (l *LinkFetcher) FetchIcons(b *charm.BundleData) (map[string][]byte, error)
FetchIcons generates the svg image tags given an appropriate URL, generating tags only for unique icons.
Source Files
Directories