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diff --git a/vendor/github.com/hashicorp/go-getter/README.md b/vendor/github.com/hashicorp/go-getter/README.md new file mode 100644 index 00000000..4a0b6a62 --- /dev/null +++ b/vendor/github.com/hashicorp/go-getter/README.md @@ -0,0 +1,253 @@ +# go-getter + +[][travis] +[][appveyor] +[][godocs] + +[travis]: http://travis-ci.org/hashicorp/go-getter +[godocs]: http://godoc.org/github.com/hashicorp/go-getter +[appveyor]: https://ci.appveyor.com/project/hashicorp/go-getter/branch/master + +go-getter is a library for Go (golang) for downloading files or directories +from various sources using a URL as the primary form of input. + +The power of this library is being flexible in being able to download +from a number of different sources (file paths, Git, HTTP, Mercurial, etc.) +using a single string as input. This removes the burden of knowing how to +download from a variety of sources from the implementer. + +The concept of a _detector_ automatically turns invalid URLs into proper +URLs. For example: "github.com/hashicorp/go-getter" would turn into a +Git URL. Or "./foo" would turn into a file URL. These are extensible. + +This library is used by [Terraform](https://terraform.io) for +downloading modules, [Otto](https://ottoproject.io) for dependencies and +Appfile imports, and [Nomad](https://nomadproject.io) for downloading +binaries. + +## Installation and Usage + +Package documentation can be found on +[GoDoc](http://godoc.org/github.com/hashicorp/go-getter). + +Installation can be done with a normal `go get`: + +``` +$ go get github.com/hashicorp/go-getter +``` + +go-getter also has a command you can use to test URL strings: + +``` +$ go install github.com/hashicorp/go-getter/cmd/go-getter +... + +$ go-getter github.com/foo/bar ./foo +... +``` + +The command is useful for verifying URL structures. + +## URL Format + +go-getter uses a single string URL as input to download from a variety of +protocols. go-getter has various "tricks" with this URL to do certain things. +This section documents the URL format. + +### Supported Protocols and Detectors + +**Protocols** are used to download files/directories using a specific +mechanism. Example protocols are Git and HTTP. + +**Detectors** are used to transform a valid or invalid URL into another +URL if it matches a certain pattern. Example: "github.com/user/repo" is +automatically transformed into a fully valid Git URL. This allows go-getter +to be very user friendly. + +go-getter out of the box supports the following protocols. Additional protocols +can be augmented at runtime by implementing the `Getter` interface. + + * Local files + * Git + * Mercurial + * HTTP + * Amazon S3 + +In addition to the above protocols, go-getter has what are called "detectors." +These take a URL and attempt to automatically choose the best protocol for +it, which might involve even changing the protocol. The following detection +is built-in by default: + + * File paths such as "./foo" are automatically changed to absolute + file URLs. + * GitHub URLs, such as "github.com/mitchellh/vagrant" are automatically + changed to Git protocol over HTTP. + * BitBucket URLs, such as "bitbucket.org/mitchellh/vagrant" are automatically + changed to a Git or mercurial protocol using the BitBucket API. + +### Forced Protocol + +In some cases, the protocol to use is ambiguous depending on the source +URL. For example, "http://github.com/mitchellh/vagrant.git" could reference +an HTTP URL or a Git URL. Forced protocol syntax is used to disambiguate this +URL. + +Forced protocol can be done by prefixing the URL with the protocol followed +by double colons. For example: `git::http://github.com/mitchellh/vagrant.git` +would download the given HTTP URL using the Git protocol. + +Forced protocols will also override any detectors. + +In the absense of a forced protocol, detectors may be run on the URL, transforming +the protocol anyways. The above example would've used the Git protocol either +way since the Git detector would've detected it was a GitHub URL. + +### Protocol-Specific Options + +Each protocol can support protocol-specific options to configure that +protocol. For example, the `git` protocol supports specifying a `ref` +query parameter that tells it what ref to checkout for that Git +repository. + +The options are specified as query parameters on the URL (or URL-like string) +given to go-getter. Using the Git example above, the URL below is a valid +input to go-getter: + + github.com/hashicorp/go-getter?ref=abcd1234 + +The protocol-specific options are documented below the URL format +section. But because they are part of the URL, we point it out here so +you know they exist. + +### Checksumming + +For file downloads of any protocol, go-getter can automatically verify +a checksum for you. Note that checksumming only works for downloading files, +not directories, but checksumming will work for any protocol. + +To checksum a file, append a `checksum` query parameter to the URL. +The paramter value should be in the format of `type:value`, where +type is "md5", "sha1", "sha256", or "sha512". The "value" should be +the actual checksum value. go-getter will parse out this query parameter +automatically and use it to verify the checksum. An example URL +is shown below: + +``` +./foo.txt?checksum=md5:b7d96c89d09d9e204f5fedc4d5d55b21 +``` + +The checksum query parameter is never sent to the backend protocol +implementation. It is used at a higher level by go-getter itself. + +### Unarchiving + +go-getter will automatically unarchive files into a file or directory +based on the extension of the file being requested (over any protocol). +This works for both file and directory downloads. + +go-getter looks for an `archive` query parameter to specify the format of +the archive. If this isn't specified, go-getter will use the extension of +the path to see if it appears archived. Unarchiving can be explicitly +disabled by setting the `archive` query parameter to `false`. + +The following archive formats are supported: + + * `tar.gz` and `tgz` + * `tar.bz2` and `tbz2` + * `zip` + * `gz` + * `bz2` + +For example, an example URL is shown below: + +``` +./foo.zip +``` + +This will automatically be inferred to be a ZIP file and will be extracted. +You can also be explicit about the archive type: + +``` +./some/other/path?archive=zip +``` + +And finally, you can disable archiving completely: + +``` +./some/path?archive=false +``` + +You can combine unarchiving with the other features of go-getter such +as checksumming. The special `archive` query parameter will be removed +from the URL before going to the final protocol downloader. + +## Protocol-Specific Options + +This section documents the protocol-specific options that can be specified +for go-getter. These options should be appended to the input as normal query +parameters. Depending on the usage of go-getter, applications may provide +alternate ways of inputting options. For example, [Nomad](https://www.nomadproject.io) +provides a nice options block for specifying options rather than in the URL. + +## General (All Protocols) + +The options below are available to all protocols: + + * `archive` - The archive format to use to unarchive this file, or "" (empty + string) to disable unarchiving. For more details, see the complete section + on archive support above. + + * `checksum` - Checksum to verify the downloaded file or archive. See + the entire section on checksumming above for format and more details. + +### Local Files (`file`) + +None + +### Git (`git`) + + * `ref` - The Git ref to checkout. This is a ref, so it can point to + a commit SHA, a branch name, etc. If it is a named ref such as a branch + name, go-getter will update it to the latest on each get. + + * `sshkey` - An SSH private key to use during clones. The provided key must + be a base64-encoded string. For example, to generate a suitable `sshkey` + from a private key file on disk, you would run `base64 -w0 <file>`. + + **Note**: Git 2.3+ is required to use this feature. + +### Mercurial (`hg`) + + * `rev` - The Mercurial revision to checkout. + +### HTTP (`http`) + +None + +### S3 (`s3`) + +S3 takes various access configurations in the URL. Note that it will also +read these from standard AWS environment variables if they're set. If +the query parameters are present, these take priority. + + * `aws_access_key_id` - AWS access key. + * `aws_access_key_secret` - AWS access key secret. + * `aws_access_token` - AWS access token if this is being used. + +#### Using IAM Instance Profiles with S3 + +If you use go-getter and want to use an EC2 IAM Instance Profile to avoid +using credentials, then just omit these and the profile, if available will +be used automatically. + +#### S3 Bucket Examples + +S3 has several addressing schemes used to reference your bucket. These are +listed here: http://docs.aws.amazon.com/AmazonS3/latest/dev/UsingBucket.html#access-bucket-intro + +Some examples for these addressing schemes: +- s3::https://s3.amazonaws.com/bucket/foo +- s3::https://s3-eu-west-1.amazonaws.com/bucket/foo +- bucket.s3.amazonaws.com/foo +- bucket.s3-eu-west-1.amazonaws.com/foo/bar + |