ft: S3C-4456 tiny version IDs

For some applications like OSE.

lib/versioning/VersionID.js

@@ -6,6 +6,10 @@
 // - rep_group_id           07 bytes        replication group identifier
 // - other_information      arbitrary       user input, such as a unique string
 
+const base62Integer = require('base62');
+const BASE62 = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
+const base62String = require('base-x')(BASE62);
+
 // the lengths of the components in bytes
 const LENGTH_TS = 14; // timestamp: epoch in ms
 const LENGTH_SEQ = 6; // position in ms slot
@@ -152,4 +156,61 @@ function decode(str) {
     }
 }
 
-module.exports = { generateVersionId, getInfVid, encode, decode };
+/* tiny version Ids constants:
+ *
+ * Note: base62Integer() cannot encode integers larger than 15 digits
+ * so we assume that TV_TOTAL <= 30 and we cut it in half. Please
+ * revisit if TV_TOTAL is greater than 30.
+ */
+const TV_TOTAL = LENGTH_TS + LENGTH_SEQ;
+const TV_HALF = TV_TOTAL / 2;
+const TV_EPAD = '0'.repeat(Math.ceil(TV_HALF * (Math.log(10) / Math.log(62))));
+const TV_DPAD = '0'.repeat(TV_HALF);
+
+/**
+ * Encode a versionId to obscure internal information contained
+ * in a version ID (less than 40 bytes).
+ *
+ * @param {string} str - the versionId to encode
+ * @return {string} - the encoded tinyVersionId
+ */
+function tinyEncode(str) {
+    const part1 = Number(str.substring(0, TV_HALF));
+    const part2 = Number(str.substring(TV_HALF, TV_TOTAL));
+    const part3 = Buffer.from(str.substring(TV_TOTAL));
+    const enc1 = base62Integer.encode(part1);
+    const enc2 = base62Integer.encode(part2);
+    const enc3 = base62String.encode(part3);
+    return (TV_EPAD + enc1).slice(-TV_EPAD.length) +
+        (TV_EPAD + enc2).slice(-TV_EPAD.length) +
+        enc3;
+}
+
+/**
+ * Decode a tinyVersionId. May return an error if the input string is
+ * invalid hex string or results in an invalid value.
+ *
+ * @param {string} str - the encoded tinyVersionId to decode
+ * @return {(string|Error)} - the decoded versionId or an error
+ */
+function tinyDecode(str) {
+    try {
+        let start = 0;
+        const enc1 = str.substring(start, start + TV_EPAD.length);
+        const orig1 = base62Integer.decode(enc1);
+        start += TV_EPAD.length;
+        const enc2 = str.substring(start, start + TV_EPAD.length);
+        const orig2 = base62Integer.decode(enc2);
+        start += TV_EPAD.length;
+        const enc3 = str.substring(start);
+        const orig3 = base62String.decode(enc3);
+        return (TV_DPAD + orig1.toString()).slice(-TV_DPAD.length) +
+            (TV_DPAD + orig2.toString()).slice(-TV_DPAD.length) +
+            orig3.toString();
+    } catch (err) {
+        // in case of exceptions caused by base62 libs
+        return err;
+    }
+}
+
+module.exports = { generateVersionId, getInfVid, encode, decode, tinyEncode, tinyDecode };

package.json

@@ -22,6 +22,8 @@
     "agentkeepalive": "^4.1.3",
     "ajv": "6.12.2",
     "async": "~2.1.5",
+    "base62": "2.0.1",
+    "base-x": "3.0.8",
     "debug": "~2.6.9",
     "diskusage": "^1.1.1",
     "ioredis": "4.9.5",

tests/unit/versioning/VersionID.js

@@ -39,4 +39,53 @@ describe('test generating versionIds', () => {
         assert.strictEqual(vids.length, count);
         assert.deepStrictEqual(vids, decoded);
     });
+
+    it('simple tiny version test', () => {
+        const vid = '98376906954349999999RG001  145.20.5';
+        const encoded = VID.tinyEncode(vid);
+        assert.strictEqual(encoded, 'aJLWKz4Ko9IjBBgXKj5KQT2G9UHv0g7P');
+        const decoded = VID.tinyDecode(encoded);
+        assert.strictEqual(vid, decoded);
+    });
+
+    it('tiny version test with smaller part1 number', () => {
+        const vid = '00000000054349999999RG001  145.20.5';
+        const encoded = VID.tinyEncode(vid);
+        const decoded = VID.tinyDecode(encoded);
+        assert.strictEqual(vid, decoded);
+    });
+
+    it('tiny version test with smaller part2 number', () => {
+        const vid = '98376906950000099999RG001  145.20.5';
+        const encoded = VID.tinyEncode(vid);
+        const decoded = VID.tinyDecode(encoded);
+        assert.strictEqual(vid, decoded);
+    });
+
+    it('tiny version test with smaller part3', () => {
+        const vid = '98376906950000099999R1  145.20.5';
+        const encoded = VID.tinyEncode(vid);
+        const decoded = VID.tinyDecode(encoded);
+        assert.strictEqual(vid, decoded);
+    });
+
+    it('tiny version test with smaller part3 - 2', () => {
+        const vid = '98376906950000099999R1x';
+        const encoded = VID.tinyEncode(vid);
+        const decoded = VID.tinyDecode(encoded);
+        assert.strictEqual(vid, decoded);
+    });
+
+    it('error case: when invalid tiny key part 3 has invalid base62 character', () => {
+        const invalidTinyVersionId = 'aJLWKz4Ko9IjBBgXKj5KQT.G9UHv0g7P';
+        const decoded = VID.tinyDecode(invalidTinyVersionId);
+        assert(decoded instanceof Error);
+    });
+
+    it('should encode and decode tiny versionIds', () => {
+        const encoded = vids.map(vid => VID.tinyEncode(vid));
+        const decoded = encoded.map(vid => VID.tinyDecode(vid));
+        assert.strictEqual(vids.length, count);
+        assert.deepStrictEqual(vids, decoded);
+    });
 });

yarn.lock

@@ -250,6 +250,18 @@ balanced-match@^1.0.0:
   resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-1.0.0.tgz#89b4d199ab2bee49de164ea02b89ce462d71b767"
   integrity sha1-ibTRmasr7kneFk6gK4nORi1xt2c=
 
+base-x@3.0.8:
+  version "3.0.8"
+  resolved "https://registry.yarnpkg.com/base-x/-/base-x-3.0.8.tgz#1e1106c2537f0162e8b52474a557ebb09000018d"
+  integrity sha512-Rl/1AWP4J/zRrk54hhlxH4drNxPJXYUaKffODVI53/dAsV4t9fBxyxYKAVPU1XBHxYwOWP9h9H0hM2MVw4YfJA==
+  dependencies:
+    safe-buffer "^5.0.1"
+
+base62@2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/base62/-/base62-2.0.1.tgz#729cfe179ed34c61e4a489490105b44ce4ea1197"
+  integrity sha512-4t4WQK7mdbcWzqEBiq6tfo2qDCeIZGXvjifJZyxHIVcjQkZJxpFtu/pa2Va69OouCkg6izZ08hKnPxroeDyzew==
+
 base64-arraybuffer@0.1.5:
   version "0.1.5"
   resolved "https://registry.yarnpkg.com/base64-arraybuffer/-/base64-arraybuffer-0.1.5.tgz#73926771923b5a19747ad666aa5cd4bf9c6e9ce8"
@@ -2191,6 +2203,11 @@ rx-lite@^3.1.2:
   resolved "https://registry.yarnpkg.com/rx-lite/-/rx-lite-3.1.2.tgz#19ce502ca572665f3b647b10939f97fd1615f102"
   integrity sha1-Gc5QLKVyZl87ZHsQk5+X/RYV8QI=
 
+safe-buffer@^5.0.1:
+  version "5.2.1"
+  resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.2.1.tgz#1eaf9fa9bdb1fdd4ec75f58f9cdb4e6b7827eec6"
+  integrity sha512-rp3So07KcdmmKbGvgaNxQSJr7bGVSVk5S9Eq1F+ppbRo70+YeaDxkw5Dd8NPN+GD6bjnYm2VuPuCXmpuYvmCXQ==
+
 safe-buffer@~5.1.0, safe-buffer@~5.1.1:
   version "5.1.2"
   resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.2.tgz#991ec69d296e0313747d59bdfd2b745c35f8828d"