imagedownloads

Documentation

Overview

Package imagedownloads implements image-downloads metadata from simplestreams.

Index

• Constants
• func DefaultSource(factory simplestreams.DataSourceFactory) func() simplestreams.DataSource
• func Filter(ftype string) simplestreams.AppendMatchingFunc
• func NewDataSource(factory simplestreams.DataSourceFactory, baseURL string) simplestreams.DataSource
• func Sort(metadata []*Metadata)
• type Metadata
  • func Fetch(fetcher imagemetadata.SimplestreamsFetcher, src []simplestreams.DataSource, ...) ([]*Metadata, *simplestreams.ResolveInfo, error)
  • func One(fetcher imagemetadata.SimplestreamsFetcher, ...) (*Metadata, error)
  • func (m *Metadata) DownloadURL(baseURL string) (*url.URL, error)

Constants

const (
	// DataType is the simplestreams datatype.
	DataType = "image-downloads"
)

Functions

func DefaultSource

func DefaultSource(factory simplestreams.DataSourceFactory) func() simplestreams.DataSource

DefaultSource creates a new signed simplestreams datasource for use with the image-downloads datatype.

func Filter

func Filter(ftype string) simplestreams.AppendMatchingFunc

Filter collects only matching products. Release and Arch are filtered by imagemetadata.ImageConstraints. So this really only let's us filter on a file type.

func NewDataSource

func NewDataSource(factory simplestreams.DataSourceFactory, baseURL string) simplestreams.DataSource

NewDataSource returns a new simplestreams.DataSource from the provided baseURL. baseURL MUST include the image stream.

func Sort

func Sort(metadata []*Metadata)

Sort sorts a slice of ImageMetadata in ascending order of their id in order to ensure the results of Fetch are ordered deterministically.

Types

type Metadata

type Metadata struct {
	Arch    string `json:"arch,omitempty"`
	Release string `json:"release,omitempty"`
	Version string `json:"version,omitempty"`
	FType   string `json:"ftype,omitempty"`
	SHA256  string `json:"sha256,omitempty"`
	Path    string `json:"path,omitempty"`
	Size    int64  `json:"size,omitempty"`
}

Metadata models the information about a particular cloud image download product.

func Fetch

func Fetch(
	fetcher imagemetadata.SimplestreamsFetcher,
	src []simplestreams.DataSource,
	cons *imagemetadata.ImageConstraint,
	ff simplestreams.AppendMatchingFunc) ([]*Metadata, *simplestreams.ResolveInfo, error)

Fetch gets product results as Metadata from the provided datasources, given some constraints and an optional filter function.

func One

func One(fetcher imagemetadata.SimplestreamsFetcher, arch, release, stream, ftype string, src func() simplestreams.DataSource) (*Metadata, error)

One gets Metadata for one content download item: The most recent of:

• architecture
• OS release
• Simplestreams stream
• File image type.

src exists to pass in a data source for testing.

func (*Metadata) DownloadURL

func (m *Metadata) DownloadURL(baseURL string) (*url.URL, error)

DownloadURL returns the URL representing the image.