Add API files endpoint.

Used to download files. It relies on `imports.paths` being set
appropriately in `etc/config.yaml` to indicate which parts of
the filesystem are accessible to users via Dougal.

lib/www/server/api/index.js

@@ -252,6 +252,12 @@ app.map({
 // // 		post: [ mw.permissions.post ],
 // // 		delete: [ mw.permissions.delete ]
 // 	},
+	'/project/:project/files/:path(*)': {
+		get: [ mw.auth.access.write, mw.files.get ]
+	},
+	'/files/?:path(*)': {
+		get: [ mw.auth.access.write, mw.files.get ]
+	},
 	'/navdata/': {
 		get: [ mw.navdata.get ],
 		'gis/:featuretype(line|point)': {

lib/www/server/api/middleware/files/get.js

@@ -0,0 +1,29 @@
+const files = require('../../../lib/files');
+
+module.exports = async function (req, res, next) {
+
+	try {
+		const entity = await files.get(req.params.path, req.params.project, req.query);
+		if (entity) {
+			if (entity.download) {
+				res.download(...entity.download, (err) => next(err));
+			} else {
+				// Directory listing
+				res.status(203).json(entity);
+				next();
+			}
+		} else {
+			throw {
+				status: 404,
+				code: "ENOENT"
+			};
+		}
+	} catch (err) {
+		if (err.code == 'ENOENT') {
+			res.status(404).json({message: err.code});
+		} else {
+			next(err);
+		}
+	}
+
+};

lib/www/server/api/middleware/files/index.js

@@ -0,0 +1,7 @@
+
+module.exports = {
+	get: require('./get'),
+	post: require('./post'),
+	put: require('./put'),
+	delete: require('./delete')
+}

lib/www/server/api/middleware/index.js

@@ -1,5 +1,6 @@
 module.exports = {
 	event: require('./event'),
+	files: require('./files'),
 	plan: require('./plan'),
 	line: require('./line'),
 	project: require('./project'),