6 files changed, 40 insertions, 4 deletions

diff --git a/src/dcp.cc b/src/dcp.cc
index 742018f5..0d67cd0c 100644
--- a/src/dcp.cc
+++ b/src/dcp.cc
@@ -449,7 +449,12 @@ DCP::write_volindex (Standard standard) const
 
 
 void
-DCP::write_xml(shared_ptr<const CertificateChain> signer, bool include_mca_subdescriptors, NameFormat name_format)
+DCP::write_xml(
+	shared_ptr<const CertificateChain> signer,
+	bool include_mca_subdescriptors,
+	NameFormat name_format,
+	optional<string> group_id
+	)
 {
 	if (_cpls.empty()) {
 		throw MiscError ("Cannot write DCP with no CPLs.");
@@ -478,7 +483,8 @@ DCP::write_xml(shared_ptr<const CertificateChain> signer, bool include_mca_subde
 				_new_annotation_text.get_value_or(String::compose("Created by libdcp %1", dcp::version)),
 				_new_issue_date.get_value_or(LocalTime().as_string()),
 				_new_issuer.get_value_or(String::compose("libdcp %1", dcp::version)),
-				_new_creator.get_value_or(String::compose("libdcp %1", dcp::version))
+				_new_creator.get_value_or(String::compose("libdcp %1", dcp::version)),
+				group_id
 				)
 			);
 	}
diff --git a/src/dcp.h b/src/dcp.h
index 9f4c93de..5802ca2e 100644
--- a/src/dcp.h
+++ b/src/dcp.h
@@ -157,7 +157,8 @@ public:
 	void write_xml(
 		std::shared_ptr<const CertificateChain> signer = std::shared_ptr<const CertificateChain>(),
 		bool include_mca_subdescriptors = true,
-		NameFormat name_format = NameFormat("%t")
+		NameFormat name_format = NameFormat("%t"),
+		boost::optional<std::string> group_id = boost::none
 	);
 
 	void resolve_refs (std::vector<std::shared_ptr<Asset>> assets);
diff --git a/src/pkl.cc b/src/pkl.cc
index 67c9067c..cb654158 100644
--- a/src/pkl.cc
+++ b/src/pkl.cc
@@ -97,6 +97,7 @@ PKL::PKL(boost::filesystem::path file, vector<dcp::VerificationNote>* notes)
 	_issue_date = pkl.string_child ("IssueDate");
 	_issuer = pkl.string_child ("Issuer");
 	_creator = pkl.string_child ("Creator");
+	_group_id = remove_urn_uuid(pkl.optional_string_child("GroupId"));
 
 	for (auto i: pkl.node_child("AssetList")->node_children("Asset")) {
 		_assets.push_back(make_shared<Asset>(i));
@@ -129,6 +130,9 @@ PKL::write_xml (boost::filesystem::path file, shared_ptr<const CertificateChain>
 	cxml::add_text_child(pkl, "IssueDate", _issue_date);
 	cxml::add_text_child(pkl, "Issuer", _issuer);
 	cxml::add_text_child(pkl, "Creator", _creator);
+	if (_group_id) {
+		cxml::add_text_child(pkl, "GroupId", "urn:uuid:" + *_group_id);
+	}
 
 	auto asset_list = cxml::add_child(pkl, "AssetList");
 	for (auto i: _assets) {
diff --git a/src/pkl.h b/src/pkl.h
index b72fa2f8..eb6ca51e 100644
--- a/src/pkl.h
+++ b/src/pkl.h
@@ -58,8 +58,16 @@ class VerificationNote;
 class PKL : public Object, public AssetList
 {
 public:
-	PKL (Standard standard, boost::optional<std::string> annotation_text, std::string issue_date, std::string issuer, std::string creator)
+	PKL(
+		Standard standard,
+		boost::optional<std::string> annotation_text,
+		std::string issue_date,
+		std::string issuer,
+		std::string creator,
+		boost::optional<std::string> group_id = boost::none
+	   )
 		: AssetList(standard, annotation_text, issue_date, issuer, creator)
+		, _group_id(group_id)
 	{}
 
 	explicit PKL(boost::filesystem::path file, std::vector<dcp::VerificationNote>* notes = nullptr);
@@ -129,8 +137,13 @@ public:
 		return _assets;
 	}
 
+	boost::optional<std::string> group_id() const {
+		return _group_id;
+	}
+
 private:
 	std::vector<std::shared_ptr<Asset>> _assets;
+	boost::optional<std::string> _group_id;
 	/** The most recent disk file used to read or write this PKL */
 	mutable boost::optional<boost::filesystem::path> _file;
 };
diff --git a/src/util.cc b/src/util.cc
index 01bc8dea..5f19d323 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -317,6 +317,17 @@ dcp::remove_urn_uuid (string raw)
 }
 
 
+optional<string>
+dcp::remove_urn_uuid(optional<string> raw)
+{
+	if (!raw) {
+		return {};
+	}
+
+	return remove_urn_uuid(*raw);
+}
+
+
 string
 dcp::openjpeg_version ()
 {
diff --git a/src/util.h b/src/util.h
index 8c4e475c..3a962520 100644
--- a/src/util.h
+++ b/src/util.h
@@ -95,6 +95,7 @@ extern std::string make_digest (ArrayData data);
 
 extern bool ids_equal (std::string a, std::string b);
 extern std::string remove_urn_uuid (std::string raw);
+extern boost::optional<std::string> remove_urn_uuid(boost::optional<std::string> raw);
 
 /** Set up various bits that the library needs.  Should be called once
  *  by client applications.