@nanggo/social-preview
Version:
Generate beautiful social media preview images from any URL
184 lines (183 loc) • 8.27 kB
JavaScript
;
/**
* Social Preview Generator
* Generate beautiful social media preview images from any URL
*/
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
var desc = Object.getOwnPropertyDescriptor(m, k);
if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
desc = { enumerable: true, get: function() { return m[k]; } };
}
Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
o[k2] = m[k];
}));
var __exportStar = (this && this.__exportStar) || function(m, exports) {
for (var p in m) if (p !== "default" && !Object.prototype.hasOwnProperty.call(exports, p)) __createBinding(exports, m, p);
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.generatePreview = generatePreview;
exports.generateImageWithTemplate = generateImageWithTemplate;
exports.generatePreviewWithDetails = generatePreviewWithDetails;
const types_1 = require("./types");
const metadata_extractor_1 = require("./core/metadata-extractor");
const image_generator_1 = require("./core/image-generator");
const registry_1 = require("./templates/registry");
const validators_1 = require("./utils/validators");
const image_security_1 = require("./utils/image-security");
const overlay_generator_1 = require("./core/overlay-generator");
const template_image_processing_1 = require("./core/template-image-processing");
const preview_cache_1 = require("./utils/preview-cache");
const sharp_cache_1 = require("./utils/sharp-cache");
// Initialize Sharp security settings
(0, image_security_1.initializeSharpSecurity)();
__exportStar(require("./exports"), exports);
// Note: Sharp caching utilities (createCachedSVG, createCachedCanvas) are used internally
// Direct Sharp instance creation is now recommended over pooling for better reliability
const FALLBACK_PREVIEW_CACHE_TTL_MS = 30_000;
/**
* Generate a social preview image from a URL
* @param url - The URL to generate preview for
* @param options - Configuration options
* @returns Buffer containing the generated image
*/
async function generatePreview(url, options = {}) {
const result = await generatePreviewWithDetails(url, options);
return result.buffer;
}
/**
* Generate image with specific template
*/
async function generateImageWithTemplate(metadata, template, options) {
// Use centralized validation gateway - returns sanitized options
const sanitizedOptions = (0, validators_1.sanitizeOptions)(options);
const width = sanitizedOptions.width || image_generator_1.DEFAULT_DIMENSIONS.width;
const height = sanitizedOptions.height || image_generator_1.DEFAULT_DIMENSIONS.height;
const quality = sanitizedOptions.quality || 90;
try {
// Validate dimensions once at the start
(0, validators_1.validateDimensions)(width, height);
// Create base image with template-specific processing
const baseImage = await (0, template_image_processing_1.processImageForTemplate)(metadata, template, width, height, sanitizedOptions);
// Generate overlay using template's overlay generator
let overlayBuffer;
if (template.overlayGenerator) {
const overlaySvg = template.overlayGenerator(metadata, width, height, options, template);
overlayBuffer = sharp_cache_1.svgCache.getCachedSVG(overlaySvg) ?? sharp_cache_1.svgCache.cacheSVG(overlaySvg);
}
else {
// Fallback to default overlay generation for custom templates
overlayBuffer = await (0, overlay_generator_1.generateDefaultOverlay)(metadata, template, width, height, options);
}
// Composite overlay on base image
const finalImage = await baseImage
.composite([
{
input: overlayBuffer,
top: 0,
left: 0,
},
])
.jpeg({
quality,
progressive: true,
mozjpeg: true
})
.toBuffer();
return finalImage;
}
catch (error) {
throw new types_1.PreviewGeneratorError(types_1.ErrorType.IMAGE_ERROR, `Failed to generate image with template: ${error instanceof Error ? error.message : String(error)}`, error);
}
}
/**
* Generate preview with full result details
*/
async function generatePreviewWithDetails(url, options = {}) {
try {
// Validate options first
(0, validators_1.validateOptions)(options);
// Set default options
const finalOptions = {
template: 'modern',
width: image_generator_1.DEFAULT_DIMENSIONS.width,
height: image_generator_1.DEFAULT_DIMENSIONS.height,
quality: 90,
cache: false,
...options,
};
const shouldCache = finalOptions.cache === true;
if (shouldCache) {
const cached = (0, preview_cache_1.getCachedPreview)(url, finalOptions);
if (cached) {
return { ...cached, cached: true };
}
}
// Extract metadata from URL once
let metadata;
try {
metadata = await (0, metadata_extractor_1.extractMetadata)(url, finalOptions.security);
// Validate metadata
if (!(0, metadata_extractor_1.validateMetadata)(metadata)) {
// Apply fallbacks if metadata is incomplete
metadata = (0, metadata_extractor_1.applyFallbacks)(metadata, url);
}
}
catch (error) {
// If metadata extraction fails completely, use fallback
if (finalOptions.fallback?.strategy === 'generate' ||
finalOptions.fallback?.strategy === 'auto') {
const buffer = await (0, image_generator_1.createFallbackImage)(url, finalOptions);
// Create minimal metadata for fallback
const fallbackMetadata = (0, metadata_extractor_1.applyFallbacks)({}, url);
const fallbackResult = {
buffer,
format: 'jpeg',
dimensions: {
width: finalOptions.width || image_generator_1.DEFAULT_DIMENSIONS.width,
height: finalOptions.height || image_generator_1.DEFAULT_DIMENSIONS.height,
},
metadata: fallbackMetadata,
template: finalOptions.template || 'modern',
cached: false,
};
if (shouldCache) {
(0, preview_cache_1.setCachedPreview)(url, finalOptions, fallbackResult, FALLBACK_PREVIEW_CACHE_TTL_MS);
}
return fallbackResult;
}
throw error;
}
// Get template configuration
const templateName = finalOptions.template || 'modern';
const template = registry_1.templates[templateName];
if (!template) {
throw new types_1.PreviewGeneratorError(types_1.ErrorType.TEMPLATE_ERROR, `Template "${templateName}" not found`);
}
// Generate image based on template - reuse metadata instead of re-extracting
const buffer = await generateImageWithTemplate(metadata, template || registry_1.templates.modern, finalOptions);
const result = {
buffer,
format: 'jpeg',
dimensions: {
width: finalOptions.width || image_generator_1.DEFAULT_DIMENSIONS.width,
height: finalOptions.height || image_generator_1.DEFAULT_DIMENSIONS.height,
},
metadata,
template: finalOptions.template || 'modern',
cached: false,
};
if (shouldCache) {
(0, preview_cache_1.setCachedPreview)(url, finalOptions, result);
}
return result;
}
catch (error) {
if (error instanceof types_1.PreviewGeneratorError) {
throw error;
}
throw new types_1.PreviewGeneratorError(types_1.ErrorType.IMAGE_ERROR, `Failed to generate preview with details for ${url}: ${error instanceof Error ? error.message : String(error)}`, error);
}
}