refactor buffer-processing logic into its own method

so you don't have to write a temp file if you've got the PDF in memory

example/example-buffer.js

@@ -0,0 +1,13 @@
+var fs = require('fs');
+var assert = require('assert');
+var PDFExtract = require('../lib').PDFExtract;
+var pdfExtract = new PDFExtract();
+var buffer = fs.readFileSync('./example.pdf');
+pdfExtract.extractBuffer(buffer, {}, function(err, data) {
+  if (err) {
+    return console.log(err);
+  }
+  var expected = require('./example-output.json');
+  assert.deepEqual(data.meta, expected.meta);
+  assert.deepEqual(data.pages, expected.pages);
+});

example/example-output.json

@@ -1,5 +1,4 @@
 {
-	"filename": "./example.pdf",
 	"meta": {
 		"info": {
 			"PDFFormatVersion": "1.3",
@@ -335,5 +334,6 @@
 		"numPages": 1,
 		"fingerprint": "4dc91a1875a6d707aec203bb021c93a0",
 		"encrypted": false
-	}
+	},
+	"filename": "./example.pdf"
 }

lib/index.js

@@ -16,76 +16,87 @@ PDFExtract.prototype.extract = function (filename, options, cb) {
 	 *
 	 * Any copyright is dedicated to the Public Domain.
 	 * http://creativecommons.org/publicdomain/zero/1.0/ */
+  var _this = this;
+  fs.readFile(filename, function(err, buffer) {
+    if (err) {
+      return cb(err);
+    }
+    return _this.extractBuffer(buffer, options, function(err, pdf) {
+      if (err) {
+        cb(err);
+      }
+      pdf.filename = filename;
+      cb(null, pdf);
+    });
+  });
+};
 
-	fs.readFile(filename, function (err, buffer) {
-		if (err) return cb(err);
-		// Loading file from file system into typed array
-		var data = new Uint8Array(buffer);
-		var pdf = {
-			filename: filename,
-			meta: {},
-			pages: []
-		};
-		// Will be using promises to load document, pages and misc data instead of callback.
-		pdfjsLib.getDocument({data: data}).then(function (doc) {
-			var numPages = doc.numPages;
-			pdf.pdfInfo = doc.pdfInfo;
-			var lastPromise; // will be used to chain promises
-			lastPromise = doc.getMetadata().then(function (data) {
-				pdf.meta = data;
-			});
-			var loadPage = function (pageNum) {
-				return doc.getPage(pageNum).then(function (page) {
-					var viewport = page.getViewport(1.0 /* scale */);
-					var pag = {
-						pageInfo: {
-							num: pageNum,
-							scale: viewport.scale,
-							rotation: viewport.rotation,
-							offsetX: viewport.offsetX,
-							offsetY: viewport.offsetY,
-							width: viewport.width,
-							height: viewport.height,
-							fontScale: viewport.fontScale
-						}
-					};
-					pdf.pages.push(pag);
-					return page.getTextContent().then(function (content) {
-						// Content contains lots of information about the text layout and styles, but we need only strings at the moment
-						pag.content = content.items.map(function (item) {
-							var x = item.transform[4];
-							var y = pag.pageInfo.height - item.transform[5];
-							if (viewport.rotation == 90) {
-								x = item.transform[5]
-								y = item.transform[4];
-							}
-							return {
-								x: x,
-								y: y,
-								str: item.str,
-								dir: item.dir,
-								width: item.width,
-								height: item.height,
-								fontName: item.fontName
-							};
-						});
-					}).then(function () {
-						// console.log('done page parsing');
-					});
-				})
-			};
-			// Loading of the first page will wait on metadata and subsequent loadings
-			// will wait on the previous pages.
-			for (var i = 1; i <= numPages; i++) {
-				lastPromise = lastPromise.then(loadPage.bind(null, i));
-			}
-			return lastPromise;
-		}).then(function () {
-			cb(null, pdf);
-		}, function (err) {
-			cb(err);
-		});
-	});
+PDFExtract.prototype.extractBuffer = function(buffer, options, cb) {
+  // Loading file from file system into typed array
+  var data = new Uint8Array(buffer);
+  var pdf = {
+    meta: {},
+    pages: []
+  };
+  // Will be using promises to load document, pages and misc data instead of callback.
+  pdfjsLib.getDocument({ data }).then(function(doc) {
+    var numPages = doc.numPages;
+    pdf.pdfInfo = doc.pdfInfo;
+    var lastPromise; // will be used to chain promises
+    lastPromise = doc.getMetadata().then(function(data) {
+      pdf.meta = data;
+    });
+    var loadPage = function(pageNum) {
+      return doc.getPage(pageNum).then(function(page) {
+        var viewport = page.getViewport(1.0 /* scale */);
+        var pag = {
+          pageInfo: {
+            num: pageNum,
+            scale: viewport.scale,
+            rotation: viewport.rotation,
+            offsetX: viewport.offsetX,
+            offsetY: viewport.offsetY,
+            width: viewport.width,
+            height: viewport.height,
+            fontScale: viewport.fontScale
+          }
+        };
+        pdf.pages.push(pag);
+        return page.getTextContent().then(function(content) {
+          // Content contains lots of information about the text layout and styles, but we need only strings at the moment
+          pag.content = content.items.map(function(item) {
+            var x = item.transform[4];
+            var y = pag.pageInfo.height - item.transform[5];
+            if (viewport.rotation == 90) {
+              x = item.transform[5];
+              y = item.transform[4];
+            }
+            return {
+              x,
+              y,
+              str: item.str,
+              dir: item.dir,
+              width: item.width,
+              height: item.height,
+              fontName: item.fontName
+            };
+          });
+        }).then(function() {
+          // console.log('done page parsing');
+        });
+      });
+    };
+    // Loading of the first page will wait on metadata and subsequent loadings
+    // will wait on the previous pages.
+    for (var i = 1; i <= numPages; i++) {
+      lastPromise = lastPromise.then(loadPage.bind(null, i));
+    }
+    return lastPromise;
+  }).then(function() {
+    cb(null, pdf);
+  }, function(err) {
+    cb(err);
+  });
 };
 
 PDFExtract.utils = utils;