Add sha512 checksum to OTA firmwares (#25)

* Add sha512 checksum to OTA firmwares

This hashes firmware during download and adds the hash to index.json.
Additionally, this PR adds `updateall.js` script which reads all
entries and runs `add.js` on each of them (for mass updates, such as the
hash algorithm or URL encoding etc).  To allow for this to happen, this
PR adds the ability to modify entries in-place via `add.js` (if called
on an existing path in the repo).

Lastly, this normalises the path for the Gledopto firmware to
lowercase its file extensions; they were previously `.OTA` in index.json
but `.ota` in the repository & in the `url` field -- something picked up
by the mass update.

* Update README.md

Co-authored-by: Koen Kanters <koenkanters94@gmail.com>

scripts/add.js

@@ -1,5 +1,6 @@
 const path = require('path');
 const fs = require('fs');
+const crypto = require('crypto');
 const ota = require('../lib/ota');
 const filenameOrURL = process.argv[2];
 const modelId = process.argv[3];
@@ -65,11 +66,15 @@ const main = async () => {
     const indexJSON = JSON.parse(fs.readFileSync('index.json'));
     const destination = path.join('images', manufacturerName, path.basename(file));
 
+    const hash = crypto.createHash('sha512');
+    hash.update(buffer);
+
     const entry = {
         fileVersion: parsed.header.fileVersion,
         fileSize: parsed.header.totalImageSize,
         manufacturerCode: parsed.header.manufacturerCode,
         imageType: parsed.header.imageType,
+        sha512: hash.digest('hex'),
     };
 
     if (modelId) {
@@ -92,7 +97,7 @@ const main = async () => {
         console.log(`Updated existing entry (${JSON.stringify(entry)})`);
         indexJSON[index] = entry;
 
-        if (entry.path) {
+        if (entry.path && entry.path !== destination) {
             fs.unlinkSync(entry.path);
         }
     } else {
@@ -100,7 +105,7 @@ const main = async () => {
         indexJSON.push(entry);
     }
 
-    if (!isURL) {
+    if (!isURL && file !== path.resolve(destination)) {
         if (!fs.existsSync(path.dirname(destination))) {
             fs.mkdirSync(path.dirname(destination));
         }

scripts/updateall.js

@@ -0,0 +1,15 @@
+const child_process = require('child_process');
+const fs = require('fs');
+const path = require('path');
+
+const main = async () => {
+    const indexJSON = JSON.parse(fs.readFileSync('index.json'));
+    indexJSON.forEach(entry => {
+        const result = child_process.execSync(`node ./scripts/add.js "${entry.path || entry.url}" "${entry.modelId || ''}"`, {
+            cwd: path.dirname(__dirname)
+        })
+        console.log(result.toString())
+    })
+}
+
+return main();