nodes.md 18 KB

Creating Workflow Nodes

This guide explains how to create custom workflow nodes for SmartBotic.

Node File Structure

Nodes are JavaScript modules located in nodes/<category>/ directories. Each node file must export:

  • configSchema - JSON Schema for node configuration
  • inputSchema - JSON Schema for input data
  • outputSchema - JSON Schema for output data
  • execute - Async function that performs the node's action

Basic Template

/**
 * @node my-node-id
 * @name My Node Name
 * @category my-category
 * @version 1.0.0
 * @description What this node does
 * @icon icon-name
 */

const configSchema = {
    type: 'object',
    properties: {
        myOption: {
            type: 'string',
            title: 'My Option',
            description: 'Description of this option',
            default: 'default-value'
        }
    },
    required: ['myOption']
};

const inputSchema = {
    type: 'object',
    properties: {
        data: {
            type: 'any',
            description: 'Input data'
        }
    }
};

const outputSchema = {
    type: 'object',
    properties: {
        result: {
            type: 'string',
            description: 'Output result'
        }
    }
};

module.exports = {
    configSchema,
    inputSchema,
    outputSchema,

    async execute(config, input, context) {
        // Your node logic here
        return {
            result: 'success'
        };
    }
};

JSDoc Metadata Tags

The comment block at the top of the file defines node metadata:

Tag Required Description
@node Yes Unique node identifier (kebab-case)
@name Yes Display name shown in UI
@category Yes Category for grouping (e.g., http, data, email)
@version Yes Semantic version (e.g., 1.0.0)
@description Yes Brief description of node functionality. Must be a single line - the parser captures only the first line of a multi-line @description
@icon No Lucide icon name (e.g., globe, mail, database)
@trigger No Add this tag if the node is a trigger (starts workflows)

Configuration Schema

The configSchema defines what options users can configure in the node editor.

Supported Field Types

// String field
myString: {
    type: 'string',
    title: 'Label',
    description: 'Help text',
    default: 'default value'
}

// Number field
myNumber: {
    type: 'number',
    title: 'Count',
    default: 10
}

// Boolean field
myBoolean: {
    type: 'boolean',
    title: 'Enable Feature',
    default: false
}

// Dropdown (enum)
myChoice: {
    type: 'string',
    title: 'Select Option',
    enum: ['option1', 'option2', 'option3'],
    default: 'option1'
}

// Object field
myHeaders: {
    type: 'object',
    title: 'Headers',
    additionalProperties: { type: 'string' }
}

Dynamic Options (Credentials)

To create a credential selector:

credentialId: {
    type: 'string',
    title: 'Credential',
    description: 'Select authentication credential',
    dynamicOptions: {
        source: 'credentials',
        filter: { type: 'bearer' }  // Filter by credential type
    }
}

Available credential types: bearer, api_key, basic, imap

Custom Outputs

Define multiple output ports:

const outputs = [
    { name: 'success', displayName: 'Success', type: 'object', color: '#10b981' },
    { name: 'error', displayName: 'Error', type: 'object', color: '#ef4444' }
];

module.exports = {
    configSchema,
    inputSchema,
    outputSchema,
    outputs,
    execute
};

Outputs That Come From Config

A node whose output count depends on how it is configured declares dynamicOutputs beside its static outputs:

const outputs = [
    { name: 'fallback', displayName: 'Fallback', type: 'any', color: '#6b7280' }
];

const dynamicOutputs = {
    from: 'rules',
    namePrefix: 'case',
    labelFrom: 'label',
    color: '#3b82f6'
};

module.exports = { configSchema, inputSchema, outputSchema, outputs, dynamicOutputs, execute };

For each entry in the placed node's config.rules, the editor draws a port named case0, case1 and so on, labelled from that entry's label field, followed by the static outputs. Port names are positional, so an edge survives editing a rule's label or value. Deleting a rule drops the edges hanging off the port that went with it.

At run time the node routes with _activeBranch, exactly as a fixed-port node does - the branch name is just computed:

return { _activeBranch: 'case' + i, ['case' + i]: data };

Multiple Inputs

A node that joins two branches names its inputs:

const inputs = [
    { name: 'input1', displayName: 'Input 1', type: 'any', required: false },
    { name: 'input2', displayName: 'Input 2', type: 'any', required: false }
];

module.exports = { configSchema, inputSchema, outputSchema, inputs, execute };

Each named input becomes its own target handle, and arrives in execute under that name - input.input1, input.input2. A node that declares no inputs keeps the single data handle it has always had.

Note the difference between a node that sets _activeBranch and one that does not: with the marker, exactly one output carries data and everything downstream of the others is skipped. Without it, every named output the node returns is live at once, which is how filter sends kept and discarded items down two paths in the same run.

Conventions These Nodes Follow

Four rules emerged while building the Tier 1 set. New nodes should follow them.

Fail loudly rather than drop data. A node that cannot do what was asked throws, with a message naming what it received. set-fields throws when keep-all mode is handed an array instead of an object; its dotted paths refuse to overwrite a value they would otherwise destroy; merge throws when an item lacks the key it was told to combine on. The alternative - returning an empty object, or bucketing everything under the string undefined - produces a workflow that keeps running and quietly produces wrong data.

Guard a configurable output name against your own reserved keys. A node that returns fixed keys alongside a user-named field must reject a name that would collide, throwing early:

if (outputField === 'count' || outputField === 'groups' || (groupBy && outputField === 'key')) {
    throw new Error('Aggregate: outputField cannot be "' + outputField +
        '", which is a reserved output name for this node. Pick another name.');
}

aggregate, sort-limit-dedupe and datetime all need this. template and json do not, because they return exactly one key and there is nothing to collide with - do not add the guard where it protects nothing. When a node builds its reserved-key list dynamically, as aggregate does for key (only reserved once groupBy is set, since that is the only time it is written), check every mode the node has, not just the always-on keys.

Config values arrive already evaluated. The engine resolves {{...}} in node config before execute() runs, and a config string that is exactly one expression keeps its native type. So a field typed as a string in the schema can legitimately hold an array at run time, which is why several nodes begin with if (Array.isArray(inputField)). That branch is not dead code. Nodes must not re-interpolate config values. template is the one deliberate exception: its templateSource: 'input' mode reads template text out of the input DATA at run time, which the engine never walks, so that text still has its {{...}} placeholders intact when execute() sees it, and calling smartbotic.utils.interpolate on it is genuine work, not a re-interpolation of something the engine already resolved.

Read paths with the shared helper. Use smartbotic.utils.getFieldValue(data, path) rather than writing a private path walker. Two older nodes, if-condition and loop, still carry their own divergent copies - loop silently skips a leading data. segment and if-condition does not - and that inconsistency is exactly what the shared helper exists to stop spreading.

Available APIs

Inside execute(), you have access to the smartbotic global object:

Logging

smartbotic.log.debug('Debug message');
smartbotic.log.info('Info message');
smartbotic.log.warn('Warning message');
smartbotic.log.error('Error message');

HTTP Requests

const response = smartbotic.http.request({
    method: 'GET',  // GET, POST, PUT, PATCH, DELETE
    url: 'https://api.example.com/data',
    headers: { 'Authorization': 'Bearer token' },
    body: JSON.stringify({ key: 'value' }),
    timeout: 30000,
    followRedirects: true
});

// Response: { status, headers, data, dataBase64 }

Sending and receiving binary

body is a text field. It is read as a UTF-8 string, so any byte sequence that is not valid UTF-8 is replaced on the way out - an image sent that way uploads successfully and arrives corrupt. There are two binary-safe paths instead.

For an API that takes a bare binary payload, such as an S3 PUT or the AT Protocol blob upload, use bodyBase64. It is decoded to raw bytes and sent as the whole body, and it wins over body when both are given:

const file = smartbotic.storage.downloadFile(fileId);

smartbotic.http.request({
    method: 'POST',
    url: 'https://bsky.social/xrpc/com.atproto.repo.uploadBlob',
    headers: { 'Content-Type': 'image/jpeg' },
    bodyBase64: file.data
});

For an API that expects a form upload, use files with formData, which builds a multipart body - see nodes/integration/telegram-send.js.

On the way back, data is also UTF-8 text and cannot carry binary. Read dataBase64 for image or file downloads.

One trap worth knowing: utils.base64Encode encodes a JavaScript string as UTF-8, so it is not a byte-preserving round trip for arbitrary bytes you build in JavaScript with String.fromCharCode. Anything at or above 0x80 becomes two bytes. Binary should come from the file store, where it never passes through a JavaScript string, rather than being assembled by hand.

Storage (Database)

// Insert document
const result = smartbotic.storage.insert('collection', { key: 'value' });
// Returns: { success, id }

// Get document
const doc = smartbotic.storage.get('collection', 'document-id');
// Returns: { found, document }

// Query documents
const results = smartbotic.storage.query('collection', { field: 'value' });
// Returns: { success, documents }

// Update document
smartbotic.storage.update('collection', 'document-id', { key: 'new-value' });

// Delete document
smartbotic.storage.delete('collection', 'document-id');

Credentials

const auth = smartbotic.credentials.get(credentialId);
if (auth.success) {
    // auth.headerName = 'Authorization' or 'X-API-Key'
    // auth.headerValue = 'Bearer <token>' or '<api-key>'
    headers[auth.headerName] = auth.headerValue;
}

Sending Email

const result = smartbotic.smtp.send({
    credentialId: config.credentialId,  // an smtp credential, or the imap one for the same mailbox
    to: ['someone@example.com'],        // a single address or an array
    cc: [],
    bcc: [],
    subject: 'Subject line',
    body: 'Message text',
    html: false,                        // true sends the body as text/html
    replyTo: '',
    from: '',                           // overrides the sender on the credential
    fromName: '',
    attachments: [
        { filename: 'note.txt', mimeType: 'text/plain', contentBase64: '...' }
    ]
});
// result.messageId - the Message-ID the mail went out with
// result.accepted  - how many addresses it was submitted for

An SMTP credential holds host, port, username, password, security (starttls, ssl or none), and optionally from_address and from_name. An IMAP credential is accepted in its place: the same account is reached on the submission port with STARTTLS, so a mailbox stored for reading mail does not have to be entered again to send it.

Utilities

// Generate UUID
const id = smartbotic.utils.uuid();

// Sleep (pause execution)
smartbotic.utils.sleep(1000);  // milliseconds, max 300000 (5 min)

// Template interpolation
const result = smartbotic.utils.interpolate('Hello {{name}}', { name: 'World' });

// Base64 encoding/decoding
const encoded = smartbotic.utils.base64Encode('data');
const decoded = smartbotic.utils.base64Decode(encoded);

// SHA256 hash
const hash = smartbotic.utils.sha256('data');  // Returns hex string

// Object utilities
const picked = smartbotic.utils.pick(obj, ['key1', 'key2']);
const omitted = smartbotic.utils.omit(obj, ['unwantedKey']);

// Read a nested value by dotted path
const city = smartbotic.utils.getFieldValue(input, 'data.user.address.city');
const second = smartbotic.utils.getFieldValue(input, 'data.items[1].id');
const howMany = smartbotic.utils.getFieldValue(input, 'data.items.length');

Missing paths return undefined. Arrays are reached with key[0] or a bare numeric segment, and .length works on an array. The path is taken literally, with no special handling of a leading data. segment.

Important Guidelines

Indentation

Use 4 spaces for indentation (consistent with existing nodes).

Avoid Inline Comments

Do NOT use // comments inside schema definitions. The parser may incorrectly interpret them:

// BAD - comment may break parsing
const configSchema = {
    type: 'object',
    properties: {
        url: {
            type: 'string',
            default: 'http://localhost:3000'  // This is the default  <- AVOID
        }
    }
};

// GOOD - no inline comments in schema
const configSchema = {
    type: 'object',
    properties: {
        url: {
            type: 'string',
            default: 'http://localhost:3000'
        }
    }
};

String Quotes

Use single quotes for string values in schemas. The parser converts them to JSON:

// GOOD
title: 'My Title'

// AVOID - embedded quotes can cause issues
description: 'Use "quotes" carefully'  // May break parsing

Error Handling

IMPORTANT: Throw errors instead of returning success: false. This ensures the workflow fails properly:

async execute(config, input, context) {
    // Validate required inputs
    if (!config.requiredField) {
        throw new Error('Required field is missing');
    }

    // Make API call
    const response = smartbotic.http.request({
        method: 'GET',
        url: config.url,
        headers: headers
    });

    // Check response status - throw on error
    if (response.status < 200 || response.status >= 300) {
        const errorMsg = typeof response.data === 'string'
            ? response.data
            : JSON.stringify(response.data);
        throw new Error(`API error (${response.status}): ${errorMsg}`);
    }

    // Return data on success (no try/catch needed for most cases)
    return {
        data: response.data
    };
}

Do NOT catch errors just to return { success: false } - let them propagate so the workflow fails.

Migrating Nodes to Database

After creating or modifying node files, migrate them to the running database:

# Get authentication token
TOKEN=$(curl -s http://localhost:8090/api/v1/auth/login \
  -H "Content-Type: application/json" \
  -d '{"username": "admin", "password": "admin"}' | jq -r '.accessToken')

# Migrate nodes
curl -X POST http://localhost:8090/api/v1/nodes/migrate \
  -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"nodesPath": "./nodes"}'

Runners automatically receive node updates via gRPC streaming.

Example: HTTP Download Node

/**
 * @node download-file
 * @name Download File
 * @category http
 * @version 1.0.0
 * @description Download a file from URL
 * @icon download
 */

const configSchema = {
    type: 'object',
    properties: {
        url: {
            type: 'string',
            title: 'URL',
            description: 'URL to download from'
        },
        timeout: {
            type: 'number',
            title: 'Timeout (ms)',
            default: 30000
        }
    },
    required: ['url']
};

const inputSchema = {
    type: 'object',
    properties: {
        url: { type: 'string', description: 'Override URL from input' }
    }
};

const outputSchema = {
    type: 'object',
    properties: {
        success: { type: 'boolean' },
        data: { type: 'string' },
        contentType: { type: 'string' }
    }
};

module.exports = {
    configSchema,
    inputSchema,
    outputSchema,

    async execute(config, input, context) {
        const url = input.url || config.url;

        smartbotic.log.info(`Downloading from ${url}`);

        try {
            const response = smartbotic.http.request({
                method: 'GET',
                url: url,
                timeout: config.timeout
            });

            if (response.status < 200 || response.status >= 300) {
                throw new Error(`HTTP ${response.status}`);
            }

            return {
                success: true,
                data: response.data,
                contentType: response.headers['content-type'] || ''
            };
        } catch (error) {
            smartbotic.log.error(`Download failed: ${error.message}`);
            return {
                success: false,
                error: error.message
            };
        }
    }
};

Trigger Nodes

Trigger nodes start workflow executions. Add @trigger to the JSDoc:

/**
 * @node my-trigger
 * @name My Trigger
 * @category triggers
 * @version 1.0.0
 * @description Triggers workflow on event
 * @icon zap
 * @trigger
 */

Triggers typically don't have input schemas (they generate initial data).