Add PDF handling

config/default.json

@@ -3,10 +3,18 @@
 	"blacklistedDomains": [],
 	"deproxifyURLs": false, // Automatically try deproxified versions of URLs
 	"identifierSearchLambda": "", // Identifier search Lambda function for text search
+	"recognizerLambda": "", // PDF recognizer Lambda function
 	"port": 1969,
 	"translators": {
 		"CrossrefREST.email": "" // Pass an email to Crossref REST API to utilize the faster servers pool
 	},
+	"s3Upload": {
+		"params": {
+			"Bucket": ""
+		},
+		"accessKeyId": "",
+		"secretAccessKey": ""
+	},
 	"userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:61.0) Gecko/20100101 Firefox/61.0",
 	"translatorsDirectory": "./modules/translators"
 }

lambda_template.yaml.j2

@@ -14,10 +14,24 @@ Resources:
       MemorySize: 2048
       Timeout: 30
       Policies:
+        - Statement:
+           Action:
+            - s3:PutObject
+            - s3:DeleteObject
+           Effect: Allow
+           Resource: !ImportValue RecognizerUploadBucketArn
         - LambdaInvokePolicy:
            FunctionName: {{ identifier_search_function_name }}
+        - LambdaInvokePolicy:
+           FunctionName: {{ recognizer_function_name }}
       Events:
         # API Gateway
+        GetAPI:
+          Type: Api
+          Properties:
+            # Proxy all GET requests to Lambda function
+            Path: /{proxy+}
+            Method: get
         PostAPI:
           Type: Api
           Properties:

package.json

@@ -20,6 +20,7 @@
     "request-promise-native": "^1.0.5",
     "serverless-http": "^1.6.0",
     "w3c-xmlserializer": "0.0.1",
+    "whatwg-mimetype": "^2.3.0",
     "wicked-good-xpath": "git+https://github.com/adomasven/wicked-good-xpath.git#e84d65d",
     "xregexp": "^4.2.0",
     "yargs": "^12.0.2"

src/http.js

@@ -29,6 +29,7 @@ var url = require('url');
 var jsdom = require('jsdom');
 var { JSDOM } = jsdom;
 var wgxpath = require('wicked-good-xpath');
+var MIMEType = require("whatwg-mimetype"); // Use the same MIME type library as JSDOM does
 
 /**
  * Functions for performing HTTP requests
@@ -154,29 +155,22 @@ Zotero.HTTP = new function() {
 		};
 
 		if (options.responseType == 'document') {
-			let dom;
-			try {
+			let mimeType = new MIMEType(response.headers['content-type']);
+
+			// Filter content-type in the same way as JSDOM does
+			if (mimeType.isHTML() || mimeType.isXML()) {
+				result.type = 'document';
 				body = decodeContent(body, response.headers['content-type']);
-				dom = new JSDOM(body, {
+				let dom = new JSDOM(body, {
 					url: result.responseURL,
-					// Inform JSDOM what content type it's parsing,
-					// so it could reject unsupported content types
+					// Inform JSDOM what content type it's parsing
 					contentType: response.headers['content-type']
 				});
-			}
-			catch (e) {
-				if (e.message.includes('not a HTML or XML content type')) {
-					Zotero.debug(e, 1)
-					throw new this.UnsupportedFormatError(result.responseURL, e.message);
-				}
-				throw e;
-			}
-			wgxpath.install(dom.window, true);
-			result.response = dom.window.document;
-
-			// Follow meta redirects
-			if (response.headers['content-type']
-					&& response.headers['content-type'].startsWith('text/html')) {
+
+				wgxpath.install(dom.window, true);
+				result.response = dom.window.document;
+
+				// Follow meta redirects in HTML and XML files
 				let meta = result.response.querySelector('meta[http-equiv=refresh]');
 				if (meta && meta.getAttribute('content')) {
 					let parts = meta.getAttribute('content').split(/;\s*url=/);
@@ -191,6 +185,19 @@ Zotero.HTTP = new function() {
 					}
 				}
 			}
+			else if (
+				options.fallbackToPDF &&
+				mimeType.essence === 'application/pdf'
+			) {
+				result.type = 'pdf';
+				result.response = body;
+			}
+			else {
+				throw new this.UnsupportedFormatError(
+					result.responseURL,
+					response.headers['content-type'] + ' is not supported'
+				);
+			}
 		}
 		else if (options.responseType == 'json') {
 			result.response = JSON.parse(body.toString());
@@ -319,7 +326,6 @@ Zotero.HTTP = new function() {
  *
  * TODO: Remove this code when https://github.com/jsdom/jsdom/issues/2495 will be solved
  */
-const MIMEType = require("whatwg-mimetype");
 const sniffHTMLEncoding = require("html-encoding-sniffer");
 const whatwgEncoding = require("whatwg-encoding");
 
@@ -389,6 +395,22 @@ function customRequest(method, requestURL, options) {
 			.on('response', function (res) {
 				if (returned) return;
 				response = res;
+
+				// Check content-type before starting the download
+				let mimeType = new MIMEType(response.headers['content-type']);
+				if (!(
+					mimeType.isHTML() ||
+					mimeType.isXML() ||
+					options.fallbackToPDF && mimeType.essence === 'application/pdf'
+				)) {
+					req.abort();
+					returned = true;
+					return reject(new Zotero.HTTP.UnsupportedFormatError(
+						requestURL,
+						response.headers['content-type'] + ' is not supported'
+					));
+				}
+
 				// Content-length doesn't always exists or it can be a length of a gzipped content,
 				// but it's still worth to do the initial size check
 				if (
@@ -399,15 +421,13 @@ function customRequest(method, requestURL, options) {
 					returned = true;
 					reject(new Zotero.HTTP.ResponseSizeError(requestURL));
 				}
-
-				// TODO: Filter content-type too
 			})
 			.on('end', function () {
 				if (returned) return;
 				returned = true;
 				resolve({response, body: Buffer.concat(buffers, bufferLength)});
 			});
 	});
-};
+}
 
 module.exports = Zotero.HTTP;

src/lambda.js

@@ -35,13 +35,16 @@ var Translators; // Translators module is cashed
 const SearchEndpoint = require('./searchEndpoint');
 const WebEndpoint = require('./webEndpoint');
 const ExportEndpoint = require('./exportEndpoint');
+const Recognizer = require('./recognizer');
 
 const app = module.exports = new Koa();
 app.use(cors);
 app.use(bodyParser({enableTypes: ['text', 'json']}));
 app.use(_.post('/web', WebEndpoint.handle.bind(WebEndpoint)));
 app.use(_.post('/search', SearchEndpoint.handle.bind(SearchEndpoint)));
 app.use(_.post('/export', ExportEndpoint.handle.bind(ExportEndpoint)));
+app.use(_.get('/recognize/getUploadParams', Recognizer.handleUpload.bind(Recognizer)));
+app.use(_.post('/recognize/process', Recognizer.handleProcess.bind(Recognizer)));
 
 Debug.init(1);