added fallback sha1 function

Author: joe-seabound

src/streaming.test.ts

@@ -14,14 +14,19 @@ jest.mock('@grafana/runtime', () => ({
 
 // Mock crypto.subtle for consistent testing
 const mockDigest = jest.fn();
-Object.defineProperty(global, 'crypto', {
-  value: {
-    subtle: {
-      digest: mockDigest,
+
+function setupDigestMock() {
+  Object.defineProperty(global, 'crypto', {
+    value: {
+      subtle: {
+        digest: mockDigest,
+      },
     },
-  },
-  writable: true,
-});
+    writable: true,
+  });
+}
+
+setupDigestMock();
 
 describe('getLiveStreamKey', () => {
   beforeEach(() => {
@@ -191,4 +196,29 @@ describe('getLiveStreamKey', () => {
     // Should pad single digit hex values with leading zeros
     expect(key).toBe('mqtt-datasource-uid/0102030a0b0c0d0e/1');
   });
+
+  describe('removing definition of crypto.subtle', ()  => {
+    beforeAll(() => {
+      Object.defineProperty(global, 'crypto', {
+        value: {
+          subtle: undefined,
+        },
+        writable: true,
+      });
+    });
+
+    afterAll(() => {
+      setupDigestMock();
+    });
+
+    it('should work with crypto.subtle undefined', async () => {
+      const datasourceUid = 'mqtt-datasource-uid';
+      const topic = 'sensor/temperature';
+
+      const key = await getLiveStreamKey(datasourceUid, topic);
+
+      // 8885fa14e6baa4b6 are the first 8 bytes of the hash of '{"topic":"sensor/temperature"}'
+      expect(key).toBe('mqtt-datasource-uid/8885fa14e6baa4b6/1');
+    });
+  });
 });

src/streaming.ts

@@ -10,7 +10,104 @@ export async function getLiveStreamKey(datasourceUid: string, topic?: string): P
 
   const orgId = config.bootData.user.orgId;
   const msgUint8 = new TextEncoder().encode(str); // encode as (utf-8) Uint8Array
-  const hashBuffer = await crypto.subtle.digest('SHA-1', msgUint8); // hash the message
+  let hashBuffer;
+  if (crypto.subtle === undefined) {
+    // Fall back to our own sha1 if we don't have crypto.subtle (e.g. not on localhost or over https)
+    hashBuffer = sha1(msgUint8);
+  }
+  else {
+    hashBuffer = await crypto.subtle.digest('SHA-1', msgUint8); // hash the message
+  }
   const hashArray = Array.from(new Uint8Array(hashBuffer.slice(0, 8))); // first 8 bytes
   return `${datasourceUid}/${hashArray.map((b) => b.toString(16).padStart(2, '0')).join('')}/${orgId}`;
 }
+
+function sha1(message: Uint8Array): ArrayBuffer {
+  let h0 = 0x67452301;
+  let h1 = 0xEFCDAB89;
+  let h2 = 0x98BADCFE;
+  let h3 = 0x10325476;
+  let h4 = 0xC3D2E1F0;
+
+  const message_length = message.length * 8;
+
+  // We need to pad with 0x80, zeroes, and then the message length as a 64-bit integer, to take us up
+  // to a multiple of 64 bytes.
+  let buf = new Uint8Array(64 * Math.ceil((message.length + 9) / 64));
+  buf.set(message);
+  buf[message.length] = 0x80;
+
+
+  // Bitwise operators truncate to 32 bits, we need to explicitly take the high bits
+  const message_length_high = Math.floor(message_length / 0x100000000);
+  buf[buf.length - 8] = (message_length_high & 0xff000000) >>> 24;
+  buf[buf.length - 7] = (message_length_high & 0x00ff0000) >>> 16;
+  buf[buf.length - 6] = (message_length_high & 0x0000ff00) >>> 8;
+  buf[buf.length - 5] = (message_length_high & 0x000000ff);
+
+  buf[buf.length - 4] = (message_length & 0xff000000) >>> 24;
+  buf[buf.length - 3] = (message_length & 0x00ff0000) >>> 16;
+  buf[buf.length - 2] = (message_length & 0x0000ff00) >>> 8;
+  buf[buf.length - 1] = (message_length & 0x000000ff);
+
+  for (let chunkIdx = 0; chunkIdx < buf.length; chunkIdx += 64) {
+    let words = []
+    for (let wordIdx = 0; wordIdx < 80; wordIdx += 1) {
+      if (wordIdx < 16) {
+        words[wordIdx] = buf[chunkIdx + (wordIdx * 4)]     << 24 |
+                         buf[chunkIdx + (wordIdx * 4) + 1] << 16 |
+                         buf[chunkIdx + (wordIdx * 4) + 2] << 8  |
+                         buf[chunkIdx + (wordIdx * 4) + 3];
+      } else {
+        const withoutRotation: number = words[wordIdx - 3] ^ words[wordIdx - 8] ^ words[wordIdx - 14] ^ words[wordIdx - 16];
+        words[wordIdx] = (withoutRotation << 1) | (withoutRotation >>> 31);
+      }
+    }
+
+    let a = h0;
+    let b = h1;
+    let c = h2;
+    let d = h3;
+    let e = h4;
+
+    for (let i = 0; i < 80; i += 1) {
+      let f;
+      let k;
+      if (i < 20) {
+        f = (b & c) | ((~b) & d);
+        k = 0x5A827999;
+      } else if (i < 40) {
+        f = b ^ c ^ d;
+        k = 0x6ED9EBA1;
+      } else if (i < 60) {
+        f = (b & c) | (b & d) | (c & d);
+        k = 0x8F1BBCDC;
+      } else {
+        f = b ^ c ^ d;
+        k = 0xCA62C1D6;
+      }
+
+      const temp = ((a << 5) | (a >>> 27)) + f + e + k + words[i];
+      e = d;
+      d = c;
+      c = (b << 30) | (b >>> 2);
+      b = a;
+      a = temp;
+    }
+
+    h0 += a
+    h1 += b
+    h2 += c
+    h3 += d
+    h4 += e
+  }
+
+  const retBuffer = new ArrayBuffer(20);
+  const view = new DataView(retBuffer);
+  view.setUint32(0, h0, false);
+  view.setUint32(4, h1, false);
+  view.setUint32(8, h2, false);
+  view.setUint32(12, h3, false);
+  view.setUint32(16, h4, false);
+  return retBuffer;
+}