Prevent newlines in JSONL

If a set of 100 ids are hydrated and not one of them is still available
the Hydrator was writing a blank line to the jsonl file. This could
cause problems for downstream users of the jsonl that are expecting each
line to contain a JSON object.

Refs #48

app/utils/twitter.js

@@ -56,8 +56,10 @@ export async function getUserSettings(auth) {
 export async function hydrateToStream(ids, out, auth, event, datasetId, tries=0) {
   try {
     const tweets = await fetchTweets(ids, auth)
-    const text = tweets.map(t => JSON.stringify(t)).join('\n')
-    out.write(text + "\n")
+    if (tweets.length > 0) {
+      const text = tweets.map(t => JSON.stringify(t)).join('\n')
+      out.write(text + "\n")
+    }
     event.sender.send(UPDATE_PROGRESS, {
       datasetId: datasetId,
       idsRead: ids.length, 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "hydrator",
-  "version": "0.0.11",
+  "version": "0.0.12",
   "description": "A desktop utility to hydrate Twitter ID datasets.",
   "main": "init.js",
   "author": {