WIP: Support for streaming multipart form data to the file system

plugins/tiddlywiki/multiwikiserver/modules/init.js

@@ -34,14 +34,19 @@ exports.startup = function() {
 		logger.alert("The plugin 'tiddlywiki/multiwikiserver' requires the better-sqlite3 npm package to be installed. Run 'npm install' in the root of the TiddlyWiki repository");
 		return;
 	}
-	// Compute the database path
-	var databasePath = path.resolve($tw.boot.wikiPath,"store/database.sqlite");
-	// Create and initialise the tiddler store
-	var SqlTiddlerStore = require("$:/plugins/tiddlywiki/multiwikiserver/sql-tiddler-store.js").SqlTiddlerStore;
+	// Create and initialise the tiddler store and upload manager
+	var SqlTiddlerStore = require("$:/plugins/tiddlywiki/multiwikiserver/sql-tiddler-store.js").SqlTiddlerStore,
+		store = new SqlTiddlerStore({
+			databasePath: path.resolve($tw.boot.wikiPath,"store/database.sqlite")
+		}),
+		UploadManager = require("$:/plugins/tiddlywiki/multiwikiserver/upload-manager.js").UploadManager,
+		uploadManager = new UploadManager({
+			inboxPath: path.resolve($tw.boot.wikiPath,"store/inbox"),
+			store: store
+		});
 	$tw.mws = {
-		store: new SqlTiddlerStore({
-			databasePath: databasePath
-		})
+		store: store,
+		uploadManager: uploadManager
 	};
 	// Create docs bag and recipe
 	$tw.mws.store.createBag("docs","TiddlyWiki Documentation from https://tiddlywiki.com/");

plugins/tiddlywiki/multiwikiserver/modules/upload-manager.js

@@ -0,0 +1,95 @@
+/*\
+title: $:/plugins/tiddlywiki/multiwikiserver/upload-manager.js
+type: application/javascript
+module-type: library
+
+A class that handles an incoming multipart/form-data stream, streaming the data to temporary files
+in the store/inbox folder. It invokes a callback when all the data is available. The callback can explicitly
+claim some or all of the files, otherwise they are deleted on return from the callback. Claimed files should
+be moved out of the store/inbox folder.
+
+\*/
+
+(function() {
+
+/*
+Create an instance of the upload manager. Options include:
+
+inboxPath - path to the inbox folder
+store - sqlTiddlerStore to use for saving tiddlers
+*/
+function UploadManager(options) {
+	const path = require("path");
+	options = options || {};
+	this.inboxPath = path.resolve(options.inboxPath,);
+	this.store = options.store;
+}
+
+/*
+Process a new multipart/form-data stream. Options include:
+
+state - provided by server.js
+recipe - optional name of recipe to write to (one of recipe or bag must be specified)
+bag - optional name of bag to write to (one of recipe or bag must be specified)
+callback - invoked as callback(err,results). Results is an array of {title:,bag_name:}
+
+formData is:
+{
+	parts: [
+		{
+			name: "fieldname",
+			filename: "filename",
+			filePath: "/users/home/mywiki/store/inbox/09cabc74-8163-4ead-a35b-4ca768f02d62/64131628-cbff-4677-b146-d85c42c232dc",
+			headers: {
+				name: "value",
+				...
+			}
+		},
+		...
+	]
+}
+*/
+UploadManager.prototype.processNewStream = function(options) {
+	let fileStream = null;
+	let fieldValue = "";
+	state.streamMultipartData({
+		cbPartStart: function(headers,name,filename) {
+			console.log(`Received file ${name} and ${filename} with ${JSON.stringify(headers)}`)
+			if(filename) {
+				fileStream = fs.createWriteStream(filename);
+			} else {
+				fieldValue = "";
+			}
+		},
+		cbPartChunk: function(chunk) {
+			if(fileStream) {
+				fileStream.write(chunk);
+			} else {
+				fieldValue = fieldValue + chunk;
+			}
+		},
+		cbPartEnd: function() {
+			if(fileStream) {
+				fileStream.end();
+				fileStream = null;
+			} else {
+				console.log("Data was " + fieldValue);
+				fieldValue = "";
+			}
+		},
+		cbFinished: function(err) {
+			if(err) {
+				state.sendResponse(400,{"Content-Type": "text/plain"},"Bad Request: " + err);
+			} else {
+				state.sendResponse(200, {"Content-Type": "text/plain"},"Multipart data processed");
+			}
+		}
+	});
+}
+
+UploadManager.prototype.close = function() {
+};
+
+exports.UploadManager = UploadManager;
+
+})();