From 2c4498502a23dc710bc52871d2f7c249dbb70435 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Fri, 9 Mar 2018 17:53:18 -0800
Subject: [PATCH] ircd::m: Add txn creation util.

---
 include/ircd/m/txn.h |  4 +++
 ircd/m/m.cc          | 64 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+)

diff --git a/include/ircd/m/txn.h b/include/ircd/m/txn.h
index 409c6c96f..51a6bd875 100644
--- a/include/ircd/m/txn.h
+++ b/include/ircd/m/txn.h
@@ -28,6 +28,10 @@ struct ircd::m::txn
 	json::property<name::pdus, json::array>
 >
 {
+	using array = std::pair<const json::value *, size_t>;
+	static string_view create_id(const mutable_buffer &out, const string_view &txn);
+	static std::string create(const array &pdu, const array &edu, const array &pdu_failure = {});
+
 	using super_type::tuple;
 	using super_type::operator=;
 };
diff --git a/ircd/m/m.cc b/ircd/m/m.cc
index 433bb7fac..fdb2fa0a9 100644
--- a/ircd/m/m.cc
+++ b/ircd/m/m.cc
@@ -1187,6 +1187,70 @@ ircd::m::exists(const id::room_alias &room_alias,
 	return function(room_alias, remote_query);
 }
 
+///////////////////////////////////////////////////////////////////////////////
+//
+// m/txn.h
+//
+
+std::string
+ircd::m::txn::create(const array &pdu,
+                     const array &edu,
+                     const array &pdu_failure)
+{
+	json::iov iov;
+	const json::iov::push push[]
+	{
+		{ iov, { "origin",            my_host()                   }},
+		{ iov, { "origin_server_ts",  ircd::time<milliseconds>()  }},
+	};
+
+	const json::iov::add_if _pdus
+	{
+		iov, pdu.second,
+		{
+			"pdus", { pdu.first, pdu.second }
+		}
+	};
+
+	const json::iov::add_if _edus
+	{
+		iov, edu.second,
+		{
+			"edus", { edu.first, edu.second }
+		}
+	};
+
+	const json::iov::add_if _pdu_failures
+	{
+		iov, pdu_failure.second,
+		{
+			"pdu_failures", { pdu_failure.first, pdu_failure.second }
+		}
+	};
+
+	return json::strung
+	{
+		iov
+	};
+}
+
+ircd::string_view
+ircd::m::txn::create_id(const mutable_buffer &out,
+                        const string_view &txn)
+{
+	const sha256::buf hash
+	{
+		sha256{txn}
+	};
+
+	const string_view txnid
+	{
+		b58encode(out, hash)
+	};
+
+	return txnid;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 //
 // m/hook.h