Add Matrix DM support - Start from Matrix side

Add Matrix DM support so Matrix users can start a DM with a Gitter user.

Fix #2671 (closed)

Dev notes

Put Matrix username last so when it gets truncated in the left-menu, it shows the Matrix user first

/matrix/5f762e89986e461e663059c2/@root:my.matrix.host

• https://matrix.org/docs/spec/client_server/latest#module-dm
• m.room.member will have content.is_direct for the invited user
• DM rooms for a given user can be looked by from m.direct events in /user/<user_id>/account_data/<type>

---

db.groups.insert({
        "lcUri" : "matrix",
        "uri" : "matrix",
        "sd" : {
                "extraAdmins" : [
                        db.users.findOne({ username: 'MadLittleMods' })._id
                ],
                "extraMembers" : [ ],
                "members" : "PUBLIC",
                "public" : true,
                "admins" : "MANUAL",
                "type" : null
        },
        "lcHomeUri" : "matrix/home",
        "homeUri" : "matrix/home",
        "name" : "Matrix",
});

db.troupes.insert({
        "lcUri" : "matrix/5f762e89986e461e663059c2/@root:my.matrix.host",
        "uri" : "matrix/5f762e89986e461e663059c2/@root:my.matrix.host",
        "topic" : "",
        "sd" : {
                "extraAdmins" : [ ],
                "extraMembers" : [
	                db.users.findOne({ username: 'MadLittleMods' })._id
            	 ],
                "members" : 'INVITE',
                "public" : false,
                "admins" : 'MANUAL',
                "type" : null
        },
        "groupId" : db.groups.findOne({ lcUri: 'matrix' })._id,
});

db.troupes.update({ "lcUri" : "matrix/5f762e89986e461e663059c2/@root:my.matrix.host",  }, {
	$set: {
	        "lcUri" : "matrix/5f762e89986e461e663059c2/@root:my.matrix.host",
	        "uri" : "matrix/5f762e89986e461e663059c2/@root:my.matrix.host",
	        "topic" : "",
	        "sd" : {
	                "extraAdmins" : [ ],
	                "extraMembers" : [
	                	 db.users.findOne({ username: 'MadLittleMods' })._id
	                ],
	                "members" : 'INVITE',
	                "public" : false,
	                "admins" : 'MANUAL',
	                "type" : null
	        },
	        "groupId" : db.groups.findOne({ lcUri: 'matrix' })._id,
	}
});

db.matricesbridgedroom.insert({
        "troupeId" : db.troupes.findOne({ lcUri: 'matrix/@root:my.matrix.host/5f762e89986e461e663059c2' }),
        "matrixRoomId" : "!URTudnLsoukCiVEQWT:my.matrix.host",
})

Todo

• Start DM conversation with Gitter user from the Matrix side
• Avatars
  • Because Gitter only has community/group avatars, we won't be able to set individual ones but we can set it as a Matrix logo.
• Add tests
• Update matrixUtils.ensureCorrectRoomState for DM rooms
  • Maybe it doesn't matter. The bridge can try and update but will fail to have permissions in a DM room.
• When someone invites others to the private room, inform the other party
• People can leave the room so we need to invite them back any time a new message is sent

Next iteration:

• Start DM conversation with Matrix user from the Gitter side -> !2168 (merged)

Future:

• Show virtualUsers in Gitter room member roster list, #2688

---

Considerations/known limitations:

• Virtual User in the member list roster
• Being able to invite others to the private room
• Being able to leave the room (although we can invite them back any time a new message is sent)
• Matrix DM's not available under the people one to one section in the left-menu