Updated docs, fix artifact bug

post-processor/compress/artifact.go

@@ -29,7 +29,7 @@ func (*Artifact) Id() string {
 }
 
 func (a *Artifact) Files() []string {
-	return a.files
+	return []string{a.Path}
 }
 
 func (a *Artifact) String() string {

website/source/docs/post-processors/compress.html.markdown

@@ -2,7 +2,7 @@
 layout: "docs"
 page_title: "compress Post-Processor"
 description: |-
-  The Packer compress post-processor takes an artifact with files (such as from VMware or VirtualBox) and gzip compresses the artifact into a single archive.
+  The Packer compress post-processor takes an artifact with files (such as from VMware or VirtualBox) and compresses the artifact into a single archive.
 ---
 
 # Compress Post-Processor
@@ -14,22 +14,33 @@ VMware or VirtualBox) and compresses the artifact into a single archive.
 
 ## Configuration
 
+### Required:
+
 You must specify the output filename. The archive format is derived from the filename.
 
-* `output` (required, string) - The path to save the compressed archive. The archive format is inferred from the filename. E.g. `.tar.gz` will be a gzipped tarball. `.zip` will be a zip file. If the extension can't be detected packer defaults to `.tar.gz` behavior but will not change the filename.
+* `output` (string) - The path to save the compressed archive. The archive
+  format is inferred from the filename. E.g. `.tar.gz` will be a gzipped
+  tarball. `.zip` will be a zip file. If the extension can't be detected packer
+  defaults to `.tar.gz` behavior but will not change the filename.
+
+  If you are executing multiple builders in parallel you should make sure
+  `output` is unique for each one. For example `packer_{{.BuildName}}_{{.Provider}}.zip`.
 
-  If you are executing multiple builders in parallel you should make sure `output` is unique for each one. For example `packer_{{.BuildName}}_{{.Provider}}.zip`.
+### Optional:
 
 If you want more control over how the archive is created you can specify the following settings:
 
-* `compression_level` (optional, integer) - Specify the compression level, for algorithms that support it, from 1 through 9 inclusive. Typically higher compression levels take longer but produce smaller files. Default if omitted is 6
-* `keep_input_artifact` (optional, bool) - Keep source files; defaults to false
+* `compression_level` (integer) - Specify the compression level, for algorithms
+  that support it, from 1 through 9 inclusive. Typically higher compression
+  levels take longer but produce smaller files. Defaults to `6`
+
+* `keep_input_artifact` (bool) - Keep source files; defaults to `false`
 
-## Supported Formats
+### Supported Formats
 
 Supported file extensions include `.zip`, `.tar`, `.gz`, `.tar.gz`, `.lz4` and `.tar.lz4`. Note that `.gz` and `.lz4` will fail if you have multiple files to compress.
 
-## Example
+## Examples
 
 Some minimal examples are shown below, showing only the post-processor configuration: