sap-sac-custom-widget

SAP Analytics Cloud Custom Widget Development

Table of Contents

• Overview
• Plugin Components
• Quick Start
• Community Sample Widgets
• Key Concepts
• Common Errors & Solutions
• Bundled Resources

Overview

This skill enables development of custom widgets for SAP Analytics Cloud (SAC). Custom widgets are Web Components that extend SAC stories and applications with custom visualizations, interactive elements, and specialized functionality.

Use this skill when:

• Building custom visualizations not available in standard SAC
• Integrating third-party charting libraries (ECharts, D3.js, Chart.js)
• Creating interactive input components for SAC applications
• Implementing specialized data displays or KPI widgets
• Extending Analytics Designer applications with custom functionality
• Troubleshooting custom widget loading or data binding issues

Requirements:

• SAC tenant with Optimized Story Experience or Analytics Designer
• JavaScript/Web Components knowledge
• External hosting (GitHub Pages, AWS S3, Azure) OR SAC-hosted resources (QRC Q2 2023+)

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Plugin Components

This plugin provides specialized agents, commands, and validation hooks for comprehensive widget development support.

Agents

Agent	Color	Purpose	Trigger Examples
widget-architect	Blue	Design widget structure, metadata, and integration patterns	"design custom widget", "plan widget architecture"
widget-debugger	Yellow	Troubleshoot loading, data binding, CORS, and runtime issues	"widget won't load", "CORS error", "data not binding"
widget-api-assistant	Green	Write JavaScript widget code, lifecycle functions, API integrations	"write widget code", "implement lifecycle functions"

Commands

Command	Usage	Description
/widget-validate	/widget-validate [file]	Validate widget.json schema and widget.js structure
/widget-generate	/widget-generate	Interactively generate widget scaffold with JSON + JS
/widget-lint	/widget-lint [file]	Performance, security, and best practices analysis

Validation Hooks

Automatic quality checks triggered on Write/Edit operations:

• widget.json: Required fields, tag naming, property types, data binding config
• widget.js: Lifecycle functions, Shadow DOM, propertiesChanged dispatch
• Performance: Resize debouncing, chart disposal, XSS prevention
• Context Reminders: Template suggestions, command recommendations

Templates

Ready-to-use scaffolds in templates/ directory:

• basic-widget.js - Minimal Web Component with all lifecycle functions
• data-bound-chart.js - ECharts widget with data binding
• styling-panel.js - Runtime customization panel
• widget.json-minimal - Bare-minimum metadata
• widget.json-complete - Full-featured metadata with all options

---

Quick Start

Minimal Custom Widget Structure

A custom widget requires two files:

1. widget.json (Metadata)

{
  "id": "com.company.mywidget",
  "version": "1.0.0",
  "name": "My Custom Widget",
  "description": "A simple custom widget",
  "vendor": "Company Name",
  "license": "MIT",
  "icon": "",
  "webcomponents": [
    {
      "kind": "main",
      "tag": "my-custom-widget",
      "url": "[https://your-host.com/widget.js",](https://your-host.com/widget.js",)
      "integrity": "",
      "ignoreIntegrity": true
    }
  ],
  "properties": {
    "title": {
      "type": "string",
      "default": "My Widget"
    }
  },
  "methods": {},
  "events": {}
}

2. widget.js (Web Component)

(function() {
  const template = document.createElement("template");
  template.innerHTML = `
    <style>
      :host {
        display: block;
        width: 100%;
        height: 100%;
      }
      .container {
        padding: 16px;
        font-family: Arial, sans-serif;
      }
    </style>
    <div class="container">
      <h3 id="title">My Widget</h3>
      <div id="content"></div>
    </div>
  `;

  class MyCustomWidget extends HTMLElement {
    constructor() {
      super();
      this._shadowRoot = this.attachShadow({ mode: "open" });
      this._shadowRoot.appendChild(template.content.cloneNode(true));
      this._props = {};
    }

    connectedCallback() {
      // Called when element is added to DOM
    }

    onCustomWidgetBeforeUpdate(changedProperties) {
      // Called BEFORE properties are updated
      this._props = { ...this._props, ...changedProperties };
    }

    onCustomWidgetAfterUpdate(changedProperties) {
      // Called AFTER properties are updated - render here
      if (changedProperties.title !== undefined) {
        this._shadowRoot.getElementById("title").textContent = changedProperties.title;
      }
    }

    onCustomWidgetResize() {
      // Called when widget is resized
    }

    onCustomWidgetDestroy() {
      // Cleanup when widget is removed
    }

    // Property getter/setter (required for SAC framework)
    get title() {
      return this._props.title;
    }
    set title(value) {
      this._props.title = value;
      this.dispatchEvent(new CustomEvent("propertiesChanged", {
        detail: { properties: { title: value } }
      }));
    }
  }

  customElements.define("my-custom-widget", MyCustomWidget);
})();

⚠️ Production Note: The ignoreIntegrity: true setting above is development only. For production deployments, generate a SHA256 integrity hash and set ignoreIntegrity: false.

---

Community Sample Widgets

SAP provides 15+ ready-to-use custom widget samples:

Repository: SAP-samples/SAC_Custom_Widgets

Category	Widgets
Charts	Funnel, Pareto, Sankey, Sunburst, Tree, Line, UI5 Gantt
KPI/Gauge	KPI Ring, Gauge Grade, Half Donut, Nested Pie, Custom Pie
Utilities	File Upload, Word Cloud, Bar Gradient, Widget Add-on Sample

Requirements: Optimized View Mode (OVM) enabled, data binding support

Note: Check third-party library licenses before production use.

---

Key Concepts

Lifecycle Functions

Essential functions called by SAC framework:

• onCustomWidgetBeforeUpdate(changedProperties) - Pre-update hook
• onCustomWidgetAfterUpdate(changedProperties) - Post-update (render here)
• onCustomWidgetResize() - Handle resize events
• onCustomWidgetDestroy() - Cleanup resources

Data Binding

Configure in widget.json to receive SAC model data:

{
  "dataBindings": {
    "myDataBinding": {
      "feeds": [
        {
          "id": "dimensions",
          "description": "Dimensions",
          "type": "dimension"
        },
        {
          "id": "measures",
          "description": "Measures",
          "type": "mainStructureMember"
        }
      ]
    }
  }
}

Access data in JavaScript:

// Get data binding
const dataBinding = this.dataBindings.getDataBinding("myDataBinding");

// Access result set
const data = this.myDataBinding.data;
const metadata = this.myDataBinding.metadata;

// Iterate over rows
this.myDataBinding.data.forEach(row => {
  const dimensionValue = row.dimensions_0.label;
  const measureValue = row.measures_0.raw;
});

Hosting Options

1. SAC-Hosted (Recommended, QRC Q2 2023+)

• Upload files directly to SAC > Files > Public Files
• Use relative paths: "/path/to/widget.js"
• Set "integrity": "" and "ignoreIntegrity": true

2. GitHub Pages

• Create repository with widget files
• Enable GitHub Pages in Settings
• Use URL: [https://username.github.io/repo/widget.js](https://username.github.io/repo/widget.js`)

3. External Web Server

• AWS S3, Azure Blob, or any HTTPS server
• Must include CORS headers: Access-Control-Allow-Origin: *

Security: Integrity Hash

For production, generate SHA256 hash:

# Generate hash
openssl dgst -sha256 -binary widget.js | openssl base64 -A

# Update JSON
"integrity": "sha256-abc123...",
"ignoreIntegrity": false

---

Common Errors & Solutions

Error	Cause	Solution
"The system couldn't load the custom widget"	Incorrect URL or hosting issue	Verify URL is accessible, check CORS
"Integrity check failed"	Hash mismatch	Regenerate hash after JS changes
Widget not appearing	Missing connectedCallback render	Call render in onCustomWidgetAfterUpdate
Properties not updating	Missing propertiesChanged dispatch	Use dispatchEvent with propertiesChanged
Data not displaying	Data binding misconfigured	Verify feeds in JSON match usage

---

Debugging

Browser DevTools

1. Open Chrome DevTools (F12)
2. Sources tab: Find widget.js, set breakpoints
3. Console tab: View console.log output
4. Network tab: Check if files load (200 status)

Debug Pattern

onCustomWidgetAfterUpdate(changedProperties) {
  console.log("Widget updated:", changedProperties);
  console.log("Current props:", this._props);
  console.log("Data binding:", this.myDataBinding?.data);
  this._render();
}

---

Widget Add-Ons (QRC Q4 2023+)

Widget Add-Ons extend built-in SAC widgets without building from scratch.

Use Cases:

• Customize chart tooltips
• Add visual elements to plot areas
• Override built-in styling

Supported Charts: Bar/Column, Stacked Bar/Column, Line, Stacked Area, Numeric Point

Key Differences:

• Only main and builder components (no styling)
• Must specify extension target (tooltip, plotArea, numericPoint)
• SAC provides chart context data via methods

See references/widget-addon-guide.md for complete implementation.

---

Bundled Resources

Templates (Ready-to-Use Code)

• templates/basic-widget.js - Minimal Web Component scaffold (~60 lines)
• templates/data-bound-chart.js - ECharts widget with SAC data binding (~120 lines)
• templates/styling-panel.js - Styling panel for runtime customization (~150 lines)
• templates/widget.json-minimal - Bare-minimum metadata (~25 lines)
• templates/widget.json-complete - Full-featured metadata (~100 lines)

Reference Documentation

1. references/json-schema-reference.md - Complete JSON schema documentation
2. references/widget-templates.md - Additional widget template patterns (6 templates)
3. references/echarts-integration.md - ECharts library integration guide
4. references/widget-addon-guide.md - Widget Add-On development (QRC Q4 2023+)
5. references/best-practices-guide.md - Performance, security, and development guidelines
6. references/advanced-topics.md - Custom types, script API types, installation
7. references/integration-and-migration.md - Script integration, content transport
8. references/script-api-reference.md - DataSource, Selection, MemberInfo APIs

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Official Documentation Links

Primary References (for skill updates):

• Custom Widget Developer Guide
• Developer Guide PDF
• Widget API PDF (2025)

Sample Widgets:

• SAP Samples Repository
• SAP Custom Widget GitHub

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Version History

v2.0.0 (2025-12-27)

• Added 3 specialized agents: widget-architect, widget-debugger, widget-api-assistant
• Added 3 slash commands: /widget-validate, /widget-generate, /widget-lint
• Added validation hooks for automatic quality checks on Write/Edit
• Added 5 production-ready templates in templates/ directory
• Enhanced plugin structure to match comprehensive plugin pattern
• Updated last verified date

v1.2.0 (2025-11-26)

• Updated SAC version reference to 2025.21
• Optimized SKILL.md length from 563 to ~200 lines
• Added Table of Contents to all 8 reference files
• Improved progressive disclosure architecture

v1.1.0 (2025-11-22)

• Added Widget Add-On feature documentation (QRC Q4 2023+)
• Added best practices guide (performance, security, development)
• Added advanced topics (custom types, script API types, installation)
• Enhanced description with additional keywords
• Increased error prevention coverage to 25+

v1.0.0 (2025-11-22)

• Initial release
• Complete JSON metadata reference
• Lifecycle functions documentation
• Data binding guide
• Styling panel implementation
• Hosting options (SAC-hosted, GitHub, external)
• Security (integrity hash, CORS)
• Common errors and debugging

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Last Verified: 2025-12-27 | SAC Version: 2025.21 | Skill Version: 2.0.0