Ep 08: Talking to the World — HTTP Request Node (Auth, Polling, Concurrency)

HTTP Request Is n8n's Swiss Army Knife

When n8n doesn't have a dedicated node for a service, HTTP Request is your universal fallback. It can manually call any REST API.

graph LR
    subgraph "HTTP Request Capabilities"
        HR[HTTP Request Node]
        HR --> M1[GET / POST / PUT / DELETE]
        HR --> M2[Headers / Body / Query Params]
        HR --> M3[OAuth2 / API Key / Bearer Token]
        HR --> M4[Auto Pagination]
        HR --> M5[Timeout & Retry]
        HR --> M6[Response: JSON / XML / Binary]
    end
    
    style HR fill:#ff6d5b,stroke:#e55a4e,color:#fff

1. Authentication Methods

API Key Auth

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// Method 1: API Key in Header (most common)
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// In n8n Credentials:
// Name: "Authorization"
// Value: "Bearer sk-xxxxxxxxxxxxxxxx"

// Method 2: API Key in Query Parameters
// "appid": "={{ $credentials.openWeatherApiKey }}"  // Secure reference

OAuth2 Flow

sequenceDiagram
    participant N8N as 🤖 n8n
    participant Auth as 🔐 OAuth Server
    participant API as 🌐 API Server
    
    N8N->>Auth: 1. Redirect to authorization page
    Auth-->>N8N: 2. User grants access → Authorization Code
    N8N->>Auth: 3. Exchange Code for Access + Refresh Token
    Auth-->>N8N: 4. Return Tokens (usually 1hr expiry)
    N8N->>API: 5. Call API with Access Token
    API-->>N8N: 6. Return data
    
    Note over N8N: On expiry: auto-refresh handled by n8n!
    N8N->>Auth: 7. Use Refresh Token to get new Access Token

2. Pagination

graph TB
    Start[Request Page 1] --> Check{Has next page?}
    Check -->|"Yes"| Next[Request next page]
    Next --> Merge[Merge Items]
    Merge --> Check
    Check -->|"No"| Done[Output all Items]
    
    style Check fill:#f59e0b,stroke:#d97706

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// Offset-based pagination
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
{
  "queryParameters": {
    "limit": 100,
    "offset": "={{ $pageCount * 100 }}"   // n8n auto-increments $pageCount
  }
  // Stop: {{ $response.body.length === 0 }}
}

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// Cursor-based pagination (modern APIs)
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
{
  "queryParameters": {
    "cursor": "={{ $response.body.next_cursor || '' }}"
  }
  // Stop: {{ !$response.body.next_cursor }}
}

3. Error Handling & Retry

// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
// Error handling configuration
// ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
{
  "options": {
    "response": {
      "neverError": true           // Don't crash on 4xx/5xx — let downstream If handle it
    },
    "timeout": 30000,              // 30s timeout (default is infinite!)
    "retry": {
      "maxTries": 3,               // Max 3 retries
      "waitBetweenTries": 1000     // 1s between retries
    }
  }
}

graph TB
    HTTP[HTTP Request] --> Check{Status Code}
    Check -->|"200"| Success[✅ Process]
    Check -->|"429"| Wait[⏳ Wait 60s] --> HTTP
    Check -->|"500"| Retry{Retries < 3?}
    Retry -->|"Yes"| HTTP
    Retry -->|"No"| Alert[🚨 Send Alert]
    
    style Check fill:#f59e0b,stroke:#d97706

Next Episode

In Ep 09, we unlock n8n's most powerful escape hatch — the Code Node — writing JavaScript and Python directly inside workflows for any data transformation.