Common Built-in Nodes

Ch09 Common Built-in Nodes

n8n ships with 400+ built-in nodes covering databases, files, email, and cryptography out of the box — no external dependencies needed. This chapter covers the six most frequently used: Send Email (SMTP), MySQL/PostgreSQL (database operations), Read/Write Binary File (filesystem), FTP/SFTP (file transfers), RSS Feed (content fetching), and Crypto (hashing and encryption), closing with a node selection cheat sheet.

Send Email Node: SMTP Mail Delivery

The Send Email node uses standard SMTP and works with Gmail, Outlook, corporate mail servers, and any SMTP-compatible service. Setup requires an SMTP credential (host, port, user, password, SSL/TLS) plus per-message fields: To, Subject, and an HTML or text body. The Attachments field accepts a binary field name from an upstream node (typically data).

Personalized bulk mail: Pair with Loop Over Items and use expressions like {{ $json.name }} in Subject and HTML to send tailored messages to each recipient without CC-exposing them all.

MySQL / PostgreSQL: Database Operations

Both nodes share the same interface. Four operation modes:

• Execute Query: Write raw SQL — most flexible, supports JOINs, stored procedures, and n8n expressions inside the query string.
• Insert: GUI field mapping; n8n auto-generates the INSERT and supports batch inserts from multiple upstream items in a single call.
• Update: Specify a WHERE key field and the columns to update.
• Delete: Specify WHERE conditions; returns affected row count.

-- Execute Query with n8n expression interpolation
SELECT o.id, o.amount, u.email
FROM orders o
JOIN users u ON o.user_id = u.id
WHERE o.created_at >= '{{ $json.startDate }}'
  AND o.status = 'pending'
LIMIT 100;

File Read / Write: Binary Data Handling

n8n stores file content in a "binary field" on each data item. Read Binary File loads a file from an absolute server path into this field; Write Binary File persists the field's content to disk. Use these nodes to handle downloaded files, LLM-generated text, or database exports.

Path permissions: The n8n process needs write access to the target directory. In Docker, mount the host directory via volumes and ensure it is writable by the node user (UID 1000).

FTP / SFTP: Remote File Transfer

Both nodes share the same operations: Download, Upload, Delete, List directory, and Rename. SFTP credentials support private-key authentication — prefer it over plain FTP for security.

Typical use case: financial system generates daily reconciliation files to FTP → n8n scheduled download → parse → insert to DB → email report. Or auto-upload generated reports to a customer's SFTP directory.

RSS Feed: Automated Content Monitoring

RSS Feed Read fetches one or more RSS/Atom feeds and outputs each entry as a separate data item with fields title, link, pubDate, and content.

// Single RSS item output structure
{
  "title": "OpenAI Releases GPT-5 Technical Report",
  "link": "https://openai.com/blog/gpt-5",
  "pubDate": "2025-04-20T08:00:00.000Z",
  "contentSnippet": "Today, OpenAI officially released..."
}

Chain it with a Cron trigger, an IF keyword filter, and an HTTP Request to Feishu to build a zero-code news-monitoring bot.

Crypto Node: Hashing and Encryption

Crypto provides cryptographic operations without any external libraries:

• Hash: MD5, SHA1, SHA256, SHA512 — produce hex digest strings for checksums and fingerprints
• HMAC: HMAC-SHA256 — used for DingTalk bot signing and GitHub webhook verification
• AES Encrypt / Decrypt: AES-128/192/256 in CBC or ECB mode — encrypt sensitive fields before writing to a database

Node Selection Cheat Sheet