From 72f6cf24852eb81796ec2e24df74a97b6d8793c4 Mon Sep 17 00:00:00 2001
From: Jannis R <mail@jannisr.de>
Date: Tue, 9 Jan 2018 16:51:42 +0100
Subject: [PATCH] /stations/:id route

---
 index.js       |  2 ++
 lib/station.js | 40 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+)
 create mode 100644 lib/station.js

diff --git a/index.js b/index.js
index d01ce21..ddc90f5 100644
--- a/index.js
+++ b/index.js
@@ -7,6 +7,7 @@ const hsts = require('hsts')
 const pkg = require('./package.json')
 const stations = require('./lib/stations')
 const allStations = require('./lib/all-stations')
+const station = require('./lib/station')
 
 const config = {
 	hostname: process.env.HOSTNAME || '2.db.transport.rest',
@@ -19,6 +20,7 @@ const config = {
 const api = createApi(hafas, config, (api) => {
 	api.get('/stations', stations)
 	api.get('/stations/all', allStations)
+	api.get('/stations/:id', station)
 })
 
 api.listen(config.port, (err) => {
diff --git a/lib/station.js b/lib/station.js
new file mode 100644
index 0000000..38fb82d
--- /dev/null
+++ b/lib/station.js
@@ -0,0 +1,40 @@
+'use strict'
+
+const stations = require('db-stations')
+
+const err400 = (msg) => {
+	const err = new Error(msg)
+	err.statusCode = 400
+	return err
+}
+
+// This is terribly inefficient, because we read all stations for every request.
+// todo: optimize it
+const route = (req, res, next) => {
+	const id = req.params.id.trim()
+	const stream = stations.full()
+
+	let found = false
+	const onStation = (station) => {
+		if (station.id !== id) return
+		found = true
+		stream.removeListener('data', onStation)
+
+		res.json(station)
+		next()
+	}
+	stream.on('data', onStation)
+
+	const onEnd = () => {
+		if (!found) return next(err400('Station not found.'))
+	}
+	stream.once('end', onEnd)
+
+	stream.once('error', (err) => {
+		stream.removeListener('data', onStation)
+		stream.removeListener('end', onEnd)
+		next(nerr)
+	})
+}
+
+module.exports = route