export: Added options for json output

Just worked, no need to do anything except add the options.

CHANGELOG

@@ -1,3 +1,9 @@
+git-annex (8.20200523) UNRELEASED; urgency=medium
+
+  * export: Added options for json output.
+
+ -- Joey Hess <id@joeyh.name>  Tue, 26 May 2020 10:20:52 -0400
+
 git-annex (8.20200522) upstream; urgency=medium
 
   * Fix bug that made enableremote of S3 and webdav remotes, that

Command/Export.hs

@@ -44,9 +44,10 @@ import qualified Data.Map as M
 import Control.Concurrent
 
 cmd :: Command
-cmd = command "export" SectionCommon
-	"export content to a remote"
-	paramTreeish (seek <$$> optParser)
+cmd = withGlobalOptions [jsonOptions, jsonProgressOption] $
+	command "export" SectionCommon
+		"export content to a remote"
+		paramTreeish (seek <$$> optParser)
 
 data ExportOptions = ExportOptions
 	{ exportTreeish :: Git.Ref

doc/git-annex-export.mdwn

@@ -86,6 +86,20 @@ so the overwritten modification is not lost.)
   the remote. You can later run `git annex sync --content` to upload
   the files to the export.
 
+* `--json`
+
+  Enable JSON output. This is intended to be parsed by programs that use
+  git-annex. Each line of output is a JSON object.
+
+* `--json-progress`
+
+  Include progress objects in JSON output.
+
+* `--json-error-messages`
+
+  Messages that would normally be output to standard error are included in
+  the json instead.
+
 # EXAMPLE
 
 	git annex initremote myremote type=directory directory=/mnt/myremote \

doc/todo/export_--json_--json-progress_--json-error-messages.mdwn

@@ -2,3 +2,5 @@ Pretty much to mimic `copy` in terms of its interfaceability with external comma
 
 [[!meta author=yoh]]
 [[!tag projects/datalad]]
+
+> easy one.. [[done]] --[[Joey]]