はじめに
こちらのページにしたがって、self-hosted n8n instanceでREST APIを使ってみます。
OpenAPI document
- self hostedは、こちら
API Keyの作成
- Settings > n8n API ページを開き、API Keyを生成する
API呼び出し
- GETの例
# For a self-hosted n8n instance
curl -X 'GET' \
'<N8N_HOST>:<N8N_PORT>/<N8N_PATH>/api/v<version-number>/workflows' \
-H 'accept: application/json' \
-H 'X-N8N-API-KEY: <your-api-key>'Workflowリストの取得
export MY_API_KEY=xxxxxxxxxx
curl -X 'GET' \
'http://localhost:5678/api/v1/workflows?active=true' \
-H 'accept: application/json' \
-H "X-N8N-API-KEY: ${MY_API_KEY}"
{
"data": [
{
"createdAt": "2025-08-10T11:40:09.843Z",
"updatedAt": "2025-08-10T23:35:07.765Z",
"id": "RDgcHfND3z2twqxf",
"name": "Nathan's workflow",
"active": true,
"isArchived": false,
"nodes": [
{
"parameters": {
"url": "https://internal.users.n8n.cloud/webhook/custom-erp",
"authentication": "genericCredentialType",
"genericAuthType": "httpHeaderAuth",
"sendHeaders": true,
"headerParameters": {
"parameters": [
{
"name": "unique_id",
"value": "c4308b47b010a1659a2ec71c7deac2d5"
}
]
},
"options": {}
},
"type": "n8n-nodes-base.httpRequest",
"typeVersion": 4.2,
"position": [
208,
0
],
"id": "485d2947-cccb-4858-bde5-c3796c2bd107",
"name": "HTTP Request",
"credentials": {
"httpHeaderAuth": {
"id": "QSKG5oHPU8omPZPg",
"name": "Header Auth account"
}
}
},
{
"parameters": {
"operation": "create",
"base": {
"__rl": true,
"value": "appmF64espQAOG4h1",
"mode": "list",
"cachedResultName": "beginner course",
"cachedResultUrl": "https://airtable.com/appmF64espQAOG4h1"
},
"table": {
"__rl": true,
"value": "tbl6Mzc2oCuEc4QWT",
"mode": "list",
"cachedResultName": "processingOrders",
"cachedResultUrl": "https://airtable.com/appmF64espQAOG4h1/tbl6Mzc2oCuEc4QWT"
},
"columns": {
"mappingMode": "autoMapInputData",
"value": {},
"matchingColumns": [],
"schema": [
{
"id": "orderID",
"displayName": "orderID",
"required": false,
"defaultMatch": false,
"canBeUsedToMatch": true,
"display": true,
"type": "number",
"readOnly": false,
"removed": false
},
{
"id": "employeeName",
"displayName": "employeeName",
"required": false,
"defaultMatch": false,
"canBeUsedToMatch": true,
"display": true,
"type": "string",
"readOnly": false,
"removed": false
}
],
"attemptToConvertTypes": false,
"convertFieldsToString": false
},
"options": {}
},
"type": "n8n-nodes-base.airtable",
"typeVersion": 2.1,
"position": [
896,
-16
],
"id": "ae3cbdc1-36ac-4866-9823-e26b321c0cdd",
"name": "Create a record",
"credentials": {
"airtableTokenApi": {
"id": "2Pf5Pq5aSQmr6jRS",
"name": "Airtable Personal Access Token account"
}
}
},
{
"parameters": {
"conditions": {
"options": {
"caseSensitive": true,
"leftValue": "",
"typeValidation": "strict",
"version": 2
},
"conditions": [
{
"id": "dcddecaf-b5fe-425f-a5be-078e711c0781",
"leftValue": "={{ $json.orderStatus }}",
"rightValue": "processing",
"operator": {
"type": "string",
"operation": "equals",
"name": "filter.operator.equals"
}
},
{
"id": "266b4382-8126-4d42-80d4-69d663e4df69",
"leftValue": "={{ $json.employeeName }}",
"rightValue": "Mario",
"operator": {
"type": "string",
"operation": "equals",
"name": "filter.operator.equals"
}
}
],
"combinator": "and"
},
"options": {}
},
"type": "n8n-nodes-base.if",
"typeVersion": 2.2,
"position": [
368,
16
],
"id": "0d4e3ec6-c3b7-408b-b88b-4abd235ec79f",
"name": "If"
},
{
"parameters": {
"assignments": {
"assignments": [
{
"id": "4b6cc025-364c-4dc4-ab6b-c970c6b9dfe9",
"name": "orderID",
"value": "={{ $json.orderID }}",
"type": "number"
},
{
"id": "e1d433bf-5a50-4dde-8fd5-8479e18a2467",
"name": "employeeName",
"value": "={{ $json.employeeName }}",
"type": "string"
}
]
},
"options": {}
},
"type": "n8n-nodes-base.set",
"typeVersion": 3.4,
"position": [
720,
-64
],
"id": "3672720f-b47d-4109-b390-6cc0713649dc",
"name": "Edit Fields"
},
{
"parameters": {
"jsCode": "let items = $input.all();\nlet totalBooked = items.length;\nlet bookedSum = 0;\n\nfor (let i=0; i < items.length; i++) {\n bookedSum = bookedSum + items[i].json.orderPrice;\n}\n\nreturn [{ json: {totalBooked, bookedSum} }];"
},
"type": "n8n-nodes-base.code",
"typeVersion": 2,
"position": [
560,
128
],
"id": "cf8bf31b-f4a1-4cfa-a29f-866eb6d3f425",
"name": "Code"
},
{
"parameters": {
"authentication": "webhook",
"content": "=This week we've {{$json[\"totalBooked\"]}} booked orders with a total value of {{$json[\"bookedSum\"]}}. My Unique ID: {{ $('HTTP Request').params[\"headerParameters\"][\"parameters\"][0][\"value\"] }}",
"options": {}
},
"type": "n8n-nodes-base.discord",
"typeVersion": 2,
"position": [
896,
160
],
"id": "672365da-5f25-40fc-946f-984e5d3f150d",
"name": "Discord",
"webhookId": "9217ea18-4139-4711-93c2-1bf99bc6a796",
"credentials": {
"discordWebhookApi": {
"id": "Rvqb7eRGgRzEzazP",
"name": "Discord Webhook account"
}
}
},
{
"parameters": {
"rule": {
"interval": [
{
"field": "weeks",
"triggerAtDay": [
1
],
"triggerAtHour": 9
}
]
}
},
"type": "n8n-nodes-base.scheduleTrigger",
"typeVersion": 1.2,
"position": [
16,
0
],
"id": "7fa9bbdc-b008-412f-88d3-56b1f04282a7",
"name": "Schedule Trigger"
},
{
"parameters": {
"jsCode": "let items = $input.all();\nlet totalBooked = items.length;\nlet bookedSum = 0;\n\nfor (let i=0; i < items.length; i++) {\n bookedSum = bookedSum + items[i].json.orderPrice;\n}\n\nreturn [{ json: {totalBooked, bookedSum} }];"
},
"type": "n8n-nodes-base.code",
"typeVersion": 2,
"position": [
528,
-112
],
"id": "7b37ab5e-b915-4dfa-a190-49067af2bf7e",
"name": "Code1"
}
],
"connections": {
"HTTP Request": {
"main": [
[
{
"node": "If",
"type": "main",
"index": 0
}
]
]
},
"If": {
"main": [
[
{
"node": "Code1",
"type": "main",
"index": 0
}
],
[
{
"node": "Code",
"type": "main",
"index": 0
}
]
]
},
"Edit Fields": {
"main": [
[
{
"node": "Create a record",
"type": "main",
"index": 0
}
]
]
},
"Code": {
"main": [
[
{
"node": "Discord",
"type": "main",
"index": 0
}
]
]
},
"Schedule Trigger": {
"main": [
[
{
"node": "HTTP Request",
"type": "main",
"index": 0
}
]
]
},
"Code1": {
"main": [
[
{
"node": "Edit Fields",
"type": "main",
"index": 0
}
]
]
}
},
"settings": {
"executionOrder": "v1"
},
"staticData": {
"node:Schedule Trigger": {
"recurrenceRules": []
}
},
"meta": {
"templateCredsSetupCompleted": true
},
"pinData": {},
"versionId": "029e814e-e442-4f53-a62f-e6e7208b2567",
"triggerCount": 1,
"tags": []
}
],
"nextCursor": null
}Credential data schemaの取得
curl -X 'GET' \
'http://localhost:5678/api/v1/credentials/schema/googleDriveOAuth2Api' \
-H 'accept: application/json' \
-H "X-N8N-API-KEY: ${MY_API_KEY}"
{
"additionalProperties": false,
"type": "object",
"properties": {
"clientId": {
"type": "string"
},
"clientSecret": {
"type": "string"
},
"oauthTokenData": {
"type": "json"
},
"notice": {
"type": "notice"
}
},
"required": [
"clientId",
"clientSecret"
]
}