Add netlify function for download statistics (#383)

Author: oeway

README.md

@@ -25,3 +25,13 @@ All the developers, contributors and community members of the BioImage.IO are re
 
 ## User Agreement
 By using the BioImage.IO website and/or viewing material on the website, you agree to become bound by the terms of this [User Agreement](./docs/terms_of_service.md). If you do not agree to the Disclaimer, Terms of Use, and Privacy Statements of this User Agreement, do not use this website or any portion thereof in any form or manner.
+
+## Development
+
+Start a development server:
+
+```bash
+ntl dev
+# or run without netlify functions: 
+npm run serve
+```

netlify.toml

@@ -0,0 +1,8 @@
+[dev] 
+  command = "npm run serve" 
+  autoLaunch = false
+  targetPort = 8080
+  port = 8083
+[build]
+  publish = "dist"
+  functions = "netlify/functions"

netlify/functions/download.js

@@ -0,0 +1,48 @@
+const axios = require('axios');
+
+// example url: https://bioimage.netlify.app/.netlify/functions/download/10.5281/zenodo.5764892/files/weights.onnx?debug=1
+exports.handler = async function(event, context) {
+  const queryParams = event.queryStringParameters;
+  const uadata = queryParams.uadata || '{"brands":[{"brand":"unknown","version":"unknown"}]}';
+
+  // Extracting the initial DOI from the path, assuming path format and initial parsing logic
+  const pathSegments = event.path.split('/').filter(segment => segment);
+  if (pathSegments.length < 7) {
+    return { statusCode: 400, body: JSON.stringify({ message: "Invalid path format." }) };
+  }
+  const doi = `${pathSegments[3]}/${pathSegments[4]}`; // Combines "10.5281" and "zenodo.XXXXX"
+  const initialDoiUrl = `https://doi.org/${doi}`;
+
+  try {
+    // Attempt to resolve the DOI URL without following redirects
+    const response = await axios.get(initialDoiUrl, { maxRedirects: 0, validateStatus: status => status >= 300 && status < 400 });
+    const finalZenodoUrl = response.headers.location;
+
+    // Extract Zenodo version ID from the redirect URL
+    const zenodoVersionIdMatch = finalZenodoUrl.match(/record\/(\d+)/);
+
+    if (!zenodoVersionIdMatch || !zenodoVersionIdMatch[1]) {
+      return { statusCode: 500, body: JSON.stringify({ message: "Failed to extract Zenodo version ID.", pathSegments, finalZenodoUrl, zenodoVersionIdMatch}) };
+    }
+    const zenodoVersionId = zenodoVersionIdMatch[1];
+
+    // Update the DOI and construct URLs with the specific version ID
+    const updatedDoi = `10.5281/zenodo.${zenodoVersionId}`;
+    const filePath = pathSegments.slice(6).join('/');
+    const actualFileUrl = `https://zenodo.org/api/records/${zenodoVersionId}/files/${filePath}/content`;
+    const matomoReportUrl = `https://bioimage.matomo.cloud/matomo.php?download=https://doi.org/${updatedDoi}&idsite=1&rec=1&r=646242&h=13&m=35&s=20&url=http://bioimage.io/#/?id=${updatedDoi}&uadata=${encodeURIComponent(uadata)}`;
+
+    if (queryParams.debug) {
+      return { statusCode: 200, body: JSON.stringify({ actualFileUrl, matomoReportUrl }) };
+    }
+
+    // Log the download event to Matomo
+    await axios.get(matomoReportUrl);
+
+    // Redirect to the actual file URL
+    return { statusCode: 302, headers: { 'Location': actualFileUrl } };
+  } catch (error) {
+    // Handle errors during the DOI resolution process or HTTP requests
+    return { statusCode: 500, body: JSON.stringify({ message: "Error during processing.", error: error.message }) };
+  }
+};