115 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
			
		
		
	
	
			115 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
| import { FreshContext, Handlers } from "$fresh/server.ts";
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| import { getImageContent } from "@lib/image.ts";
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| import { createLogger } from "@lib/log/index.ts";
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| 
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| const log = createLogger("api/image");
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| 
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| // Constants for image processing
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| const CONFIG = {
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|   maxDimension: 2048,
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|   minDimension: 1,
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|   acceptedMimeTypes: new Set([
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|     "image/jpeg",
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|     "image/png",
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|     "image/webp",
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|     "image/gif",
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|   ]),
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| };
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| 
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| interface ImageParams {
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|   image: string;
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|   height: number;
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|   width: number;
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| }
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| 
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| /**
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|  * Validates and parses URL parameters for image processing
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|  */
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| function parseParams(reqUrl: URL): ImageParams | string {
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|   try {
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|     const image = reqUrl.searchParams.get("image")?.replace(/^\//, "");
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|     if (!image) {
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|       return "Missing 'image' query parameter.";
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|     }
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| 
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|     // Parse dimensions with defaults
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|     const height = Math.floor(Number(reqUrl.searchParams.get("height")) || 0);
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|     const width = Math.floor(Number(reqUrl.searchParams.get("width")) || 0);
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| 
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|     // Validate dimensions
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|     if (height < 0 || width < 0) {
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|       return "Negative height or width is not supported.";
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|     }
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| 
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|     if (height > CONFIG.maxDimension || width > CONFIG.maxDimension) {
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|       return `Width and height cannot exceed ${CONFIG.maxDimension}.`;
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|     }
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| 
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|     // If dimensions are provided, ensure they're not too small
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|     if (
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|       (height > 0 && height < CONFIG.minDimension) ||
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|       (width > 0 && width < CONFIG.minDimension)
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|     ) {
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|       return `Dimensions must be at least ${CONFIG.minDimension} pixel.`;
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|     }
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| 
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|     return { image, height, width };
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|   } catch (error) {
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|     log.error("Error parsing parameters:", error);
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|     return "Invalid parameters provided.";
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|   }
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| }
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| // Helper function to generate ETag
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| async function generateETag(content: ArrayBuffer): Promise<string> {
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|   const hashBuffer = await crypto.subtle.digest("SHA-256", content);
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|   return `"${Array.from(new Uint8Array(hashBuffer))
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|     .map((b) => b.toString(16).padStart(2, "0"))
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|     .join("")
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|     }"`;
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| }
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| 
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| async function GET(req: Request, _ctx: FreshContext): Promise<Response> {
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|   try {
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|     const url = new URL(req.url);
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|     const params = parseParams(url);
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| 
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|     if (typeof params === "string") {
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|       return new Response(params, {
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|         status: 400,
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|         headers: { "Content-Type": "text/plain" },
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|       });
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|     }
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| 
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|     const imageUrl = params.image.startsWith("resources")
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|       ? `https://marka.max-richter.dev/${params.image.replace(/^\//, "")}`
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|       : params.image;
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| 
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|     log.debug("Processing image request:", { imageUrl, params });
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| 
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|     const image = await getImageContent(imageUrl, params);
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| 
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|     // Generate ETag based on image content
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|     const eTag = await generateETag(image.content);
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| 
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|     // Set caching headers
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|     return new Response(image.content, {
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|       headers: {
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|         "Content-Type": image.mimeType,
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|         "Cache-Control": "public, max-age=31536000, immutable", // Cache for 1 year
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|         "ETag": eTag,
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|         "Last-Modified": new Date().toUTCString(), // Replace with image's actual modified date if available
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|       },
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|     });
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|   } catch (error) {
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|     log.error("Error processing image:", error);
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|     return new Response("Internal server error", {
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|       status: 500,
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|       headers: { "Content-Type": "text/plain" },
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|     });
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|   }
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| }
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| 
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| export const handler: Handlers = {
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|   GET,
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| };
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