You do not need to use the Move Binary Data node. You need a function node to map the base64 image to a binary structure in n8n and then reference the binary key in the Write Binary File node. Check the example below. Btw you might need to do a split in the incoming string to remove the data:image/jpeg,base64
.
Instead of sending the image to the webhook as base64, it should be much simple to send the image as binary when making the HTTP request to the Webhook. That way, n8n would do the transformation for you, meaning the Function node does have to be used.
{
"nodes": [
{
"parameters": {},
"name": "Start",
"type": "n8n-nodes-base.start",
"typeVersion": 1,
"position": [
250,
300
]
},
{
"parameters": {
"values": {
"string": [
{
"name": "logo",
"value": 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}
]
},
"options": {}
},
"name": "Set",
"type": "n8n-nodes-base.set",
"typeVersion": 1,
"position": [
520,
300
]
},
{
"parameters": {
"functionCode": "return [\n {\n json: {},\n binary: {\n data: {\n\t\t\t\tdata: items[0].json.logo,\n\t\t\t\tmimeType: 'image/png', // Optional but should be set if possible (optional)\n\t\t\t\tfileExtension: 'png', // Optional but should be set if possible (optional)\n\t\t\t\tfileName: 'logo.png', // Optional but should be set if possible (optional)\n\t\t\t} }\n }\n]"
},
"name": "Function",
"type": "n8n-nodes-base.function",
"typeVersion": 1,
"position": [
770,
300
]
},
{
"parameters": {
"fileName": "image.png"
},
"name": "Write Binary File",
"type": "n8n-nodes-base.writeBinaryFile",
"typeVersion": 1,
"position": [
990,
300
]
}
],
"connections": {
"Start": {
"main": [
[
{
"node": "Set",
"type": "main",
"index": 0
}
]
]
},
"Set": {
"main": [
[
{
"node": "Function",
"type": "main",
"index": 0
}
]
]
},
"Function": {
"main": [
[
{
"node": "Write Binary File",
"type": "main",
"index": 0
}
]
]
}
}
}