ChooseString returns the first non-empty value.

DownloadableURL processes a URL that may also be a file path and returns a completely valid URL.

HashForType returns the Hash implementation for the given string type, or nil if the type is not supported.

MultistepDebugFn will return a proper multistep.DebugPauseFn to use for debugging if you're using multistep in your builder.

NewDownloadClient returns a new DownloadClient for the given configuration.

NewRunner returns a multistep.Runner that runs steps augmented with support for -debug and -on-error command line arguments.

NewRunnerWithPauseFn returns a multistep.Runner that runs steps augmented with support for -debug and -on-error command line arguments.

Retry retries a function up to numTries times with exponential backoff.

ScrubConfig is a helper that returns a string representation of any struct with the given values stripped out.

PackerKeyDefault 100ms is appropriate for shared build infrastructure while a shorter delay (e.g.

PackerKeyEnv is used to specify the key interval (delay) between keystrokes sent to the VM, typically in boot commands.

A DownloadClient helps download, verify checksums, etc.

DownloadConfig is the configuration given to instantiate a new download instance.

HTTPConfig contains configuration for the local HTTP Server.

HTTPDownloader is an implementation of Downloader that downloads files over HTTP.

ISOConfig contains configuration for downloading ISO images.

PackerConfig is a struct that contains the configuration keys that are sent by packer, properly tagged already so mapstructure can load them.

StepCreateFloppy will create a floppy disk with the given files.

StepDownload downloads a remote file using the download client within this package.

This step creates and runs the HTTP server that is serving files from the directory specified by the 'http_directory` configuration parameter in the template.

StepProvision runs the provisioners.

A downloader is responsible for actually taking a remote URL and downloading it.