Move content-disposition setting into a method on `res`

services/web/app/coffee/Features/Compile/CompileController.coffee

@@ -85,12 +85,10 @@ module.exports = CompileController =
 			res.contentType("application/pdf")
 			if !!req.query.popupDownload
 				logger.log project_id: project_id, "download pdf as popup download"
-				res.header(
-					'Content-Disposition', "attachment; filename=#{encodeURIComponent(project.getSafeProjectName())}.pdf"
-				)
+				res.setContentDisposition('attachment', {filename: "#{project.getSafeProjectName()}.pdf"})
 			else
 				logger.log project_id: project_id, "download pdf to embed in browser"
-				res.header('Content-Disposition', "filename=#{project.getSafeProjectName()}.pdf")
+				res.setContentDisposition('', {filename: "#{project.getSafeProjectName()}.pdf"})
 
 			rateLimit (err, canContinue)->
 				if err?

services/web/app/coffee/Features/Downloads/ProjectDownloadsController.coffee

@@ -15,9 +15,9 @@ module.exports = ProjectDownloadsController =
 				return next(error) if error?
 				ProjectZipStreamManager.createZipStreamForProject project_id, (error, stream) ->
 					return next(error) if error?
-					res.header(
-						"Content-Disposition",
-						"attachment; filename=#{encodeURIComponent(project.name)}.zip"
+					res.setContentDisposition(
+						'attachment',
+						{filename: "#{project.name}.zip"}
 					)
 					res.contentType('application/zip')
 					stream.pipe(res)
@@ -30,9 +30,9 @@ module.exports = ProjectDownloadsController =
 			return next(error) if error?
 			ProjectZipStreamManager.createZipStreamForMultipleProjects project_ids, (error, stream) ->
 				return next(error) if error?
-				res.header(
-					"Content-Disposition",
-					"attachment; filename=ShareLaTeX Projects (#{project_ids.length} items).zip"
+				res.setContentDisposition(
+					'attachment',
+					{filename: "ShareLaTeX Projects (#{project_ids.length} items).zip"}
 				)
 				res.contentType('application/zip')
 				stream.pipe(res)

services/web/app/coffee/Features/FileStore/FileStoreController.coffee

@@ -35,5 +35,5 @@ module.exports =
 				if (is_mobile_safari(user_agent) and is_html(file))
 					logger.log filename: file.name, user_agent: user_agent, "sending html file to mobile-safari as plain text"
 					res.setHeader('Content-Type', 'text/plain')
-				res.setHeader("Content-Disposition", "attachment; filename=#{encodeURIComponent(file.name)}")
+				res.setContentDisposition('attachment', {filename: file.name})
 				stream.pipe res

services/web/app/coffee/infrastructure/ExpressLocals.coffee

@@ -71,6 +71,19 @@ module.exports = (app, webRouter, apiRouter)->
 		res.locals.session = req.session
 		next()
 
+	addSetContentDisposition = (req, res, next) ->
+		res.setContentDisposition = (type, opts) ->
+			directives = for k, v of opts
+				"#{k}=\"#{encodeURIComponent(v)}\""
+			contentDispositionValue = "#{type}; #{directives.join('; ')}"
+			res.setHeader(
+				'Content-Disposition',
+				contentDispositionValue
+			)
+		next()
+	webRouter.use addSetContentDisposition
+	apiRouter.use addSetContentDisposition
+
 	webRouter.use (req, res, next)->
 
 		cdnBlocked = req.query.nocdn == 'true' or req.session.cdnBlocked

services/web/test/UnitTests/coffee/Compile/CompileControllerTests.coffee

@@ -136,8 +136,8 @@ describe "CompileController", ->
 					.should.equal true
 
 			it "should set the content-disposition header with the project name", ->
-				@res.header
-					.calledWith("Content-Disposition", "filename=#{encodeURIComponent(@safe_name)}.pdf")
+				@res.setContentDisposition
+					.calledWith('', {filename: "#{@safe_name}.pdf"})
 					.should.equal true
 
 			it "should increment the pdf-downloads metric", ->

services/web/test/UnitTests/coffee/Downloads/ProjectDownloadsControllerTests.coffee

@@ -59,10 +59,10 @@ describe "ProjectDownloadsController", ->
 			@Project.findById.calledWith(@project_id, "name").should.equal(true)
 
 		it "should name the downloaded file after the project", ->
-			@res.header
+			@res.setContentDisposition
 				.calledWith(
-					"Content-Disposition",
-					"attachment; filename=#{encodeURIComponent(@project_name)}.zip")
+					'attachment',
+					{filename: "#{@project_name}.zip"})
 				.should.equal true
 
 		it "should record the action via Metrics", ->
@@ -107,10 +107,10 @@ describe "ProjectDownloadsController", ->
 				.should.equal true
 
 		it "should name the downloaded file after the project", ->
-			@res.header
+			@res.setContentDisposition
 				.calledWith(
-					"Content-Disposition",
-					"attachment; filename=ShareLaTeX Projects (2 items).zip")
+					'attachment',
+					{filename: "ShareLaTeX Projects (2 items).zip"})
 				.should.equal true
 
 		it "should record the action via Metrics", ->

services/web/test/UnitTests/coffee/FileStore/FileStoreControllerTests.coffee

@@ -29,6 +29,7 @@ describe "FileStoreController", ->
 			get: (key) -> undefined
 		@res =
 			setHeader: sinon.stub()
+			setContentDisposition: sinon.stub()
 		@file =
 			name: "myfile.png"
 
@@ -62,8 +63,8 @@ describe "FileStoreController", ->
 
 		it "should set the Content-Disposition header", (done)->
 			@stream.pipe = (des)=>
-				@res.setHeader.calledWith(
-					"Content-Disposition", "attachment; filename=#{encodeURIComponent(@file.name)}"
+				@res.setContentDisposition.calledWith(
+					"attachment", {filename: @file.name}
 				).should.equal true
 				done()
 			@controller.getFile @req, @res

services/web/test/UnitTests/coffee/helpers/MockResponse.coffee

@@ -70,6 +70,8 @@ class MockResponse
 	setHeader: (header, value) ->
 		@headers[header] = value
 
+	setContentDisposition: sinon.stub()
+
 	setTimeout: (@timout)->
 
 	header: sinon.stub()