Workflow: Matrix Cron Automate

{
    "id": "9",
    "name": "Coffee Bot (Matrix)",
    "nodes": [
        {
            "name": "Greetings",
            "type": "n8n-nodes-base.matrix",
            "position": [
                670,
                240
            ],
            "parameters": {
                "text": "\ud83d\udc4b Happy Monday Groups for this week's virtual coffee are:",
                "roomId": "Enter your Room ID"
            },
            "credentials": {
                "matrixApi": "Matrix Creds"
            },
            "typeVersion": 1
        },
        {
            "name": "Employees in coffee chat channel",
            "type": "n8n-nodes-base.matrix",
            "position": [
                880,
                240
            ],
            "parameters": {
                "roomId": "Enter your Room ID",
                "filters": {
                    "membership": ""
                },
                "resource": "roomMember"
            },
            "credentials": {
                "matrixApi": "Enter Your Matrix Credentials"
            },
            "typeVersion": 1
        },
        {
            "name": "Weekly trigger on monday1",
            "type": "n8n-nodes-base.cron",
            "position": [
                480,
                240
            ],
            "parameters": {
                "triggerTimes": {
                    "item": [
                        {
                            "hour": 10,
                            "mode": "everyWeek"
                        }
                    ]
                }
            },
            "typeVersion": 1
        },
        {
            "name": "Divide into groups",
            "type": "n8n-nodes-base.function",
            "notes": "This still needs to be reconfigured to grab the information from the second Matrix node. Have an issue with the ",
            "position": [
                1090,
                240
            ],
            "parameters": {
                "functionCode": "const ideal_group_size = 3;\nlet groups = [];\nlet data_as_array = [];\nlet newItems = [];\n\n\/\/ Take all the users and add them to an array\nfor (let j = 0; j < items.length; j++) {\n  data_as_array.push({username: items[j].json.user_id});\n}\n\n\/\/ Fisher-Yates (aka Knuth) Shuffle\nfunction shuffle(array) {\n  var currentIndex = array.length, temporaryValue, randomIndex;\n\n  \/\/ While there remain elements to shuffle...\n  while (0 !== currentIndex) {\n\n    \/\/ Pick a remaining element...\n    randomIndex = Math.floor(Math.random() * currentIndex);\n    currentIndex -= 1;\n\n    \/\/ And swap it with the current element.\n    temporaryValue = array[currentIndex];\n    array[currentIndex] = array[randomIndex];\n    array[randomIndex] = temporaryValue;\n  }\n\n  return array;\n}\n\n\/\/ Randomize the sequence of names in the array\ndata_as_array = shuffle(data_as_array);\n\n\/\/ Create groups of ideal group size (3)\nfor (let i = 0; i < data_as_array.length; i += ideal_group_size) {\n  groups.push(data_as_array.slice(i, i + ideal_group_size));\n}\n\n\/\/ Make sure that no group has just one person. If it does, take\n\/\/ one from previous group and add it to that group \nfor (let k = 0; k < groups.length; k++) {\n  if (groups[k].length === 1) {\n    groups[k].push(groups[k-1].shift());\n  }\n}\n\nfor (let l = 0; l < groups.length; l++) {\n    newItems.push({json: {groupsUsername: groups[l].map(a=> a.username)}})\n}\n\nreturn newItems;\n"
            },
            "typeVersion": 1
        },
        {
            "name": "Announce groups",
            "type": "n8n-nodes-base.matrix",
            "position": [
                1290,
                240
            ],
            "parameters": {
                "text": "=\u2600\ufe0f {{$node[\"Divide into groups\"].json[\"groupsUsername\"].join(', ')}}",
                "roomId": "!hobuowPzLuKnojiyfV:matrix.org"
            },
            "credentials": {
                "matrixApi": "Matrix Creds"
            },
            "typeVersion": 1
        }
    ],
    "active": true,
    "settings": [],
    "connections": {
        "Greetings": {
            "main": [
                [
                    {
                        "node": "Employees in coffee chat channel",
                        "type": "main",
                        "index": 0
                    }
                ]
            ]
        },
        "Divide into groups": {
            "main": [
                [
                    {
                        "node": "Announce groups",
                        "type": "main",
                        "index": 0
                    }
                ]
            ]
        },
        "Weekly trigger on monday1": {
            "main": [
                [
                    {
                        "node": "Greetings",
                        "type": "main",
                        "index": 0
                    }
                ]
            ]
        },
        "Employees in coffee chat channel": {
            "main": [
                [
                    {
                        "node": "Divide into groups",
                        "type": "main",
                        "index": 0
                    }
                ]
            ]
        }
    }
}