Refactor to remove nested .then calls

diff --git a/index.html b/index.html
index 69010a16b9398fde5f2079a092251a7b19c88dc4..e8abd88bd697f020d81a91568df7bc2ea1696c4c 100644 (file)
--- a/index.html
+++ b/index.html
@@ -75,23 +75,18 @@
   </main>
 
   <script type="module">
-    document.querySelector('form').addEventListener('submit', async e => {
-      e.preventDefault();
-      const contract = e.target.elements['contract'].value;
-      const rpc = e.target.elements['rpc'].value;
-      const slotOutput = e.target.elements['slot-output'];
-      const eventOutput = e.target.elements['event-output'];
-
-      const slotPayload = [];
+    async function slotLookup(rpc, contract) {
       const slots = {
         // ERC-1967
         'Logic contract address': '0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc', // keccak256('eip1967.proxy.implementation') - 1
         'Beacon contract address': '0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50', // keccak256('eip1967.proxy.beacon') - 1
         'Admin address': '0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103', // keccak256('eip1967.proxy.admin') - 1
         // ZeppelinOS (used in OpenZeppelin contracts v2 and below, predecessor to ERC-1967)
-        'Admin address (ZeppelinOS)': '0x10d6a54a4754c8869d6886b5f5d7fbfa5b4522237ea5c60d11bc4e7a1ff9390b', // keccak256('org.zeppelinos.proxy.admin')
         'Implementation address (ZeppelinOS)': '0x7050c9e0f4ca769c69bd3a8ef740bc37934f8e2c036e5a723fd8ee048ed3f8c3', // keccak256('org.zeppelinos.proxy.implementation')
+        'Admin address (ZeppelinOS)': '0x10d6a54a4754c8869d6886b5f5d7fbfa5b4522237ea5c60d11bc4e7a1ff9390b' // keccak256('org.zeppelinos.proxy.admin')
       }
+
+      const slotPayload = [];
       for (const [key, value] of Object.entries(slots)) {
         slotPayload.push({
           jsonrpc: '2.0',
@@ -101,12 +96,30 @@
         });
       }
 
-      const eventPayload = [];
+      const response = await fetch(rpc, {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify(slotPayload)
+      }).then(r => r.json());
+
+      const output = [];
+      for (const item of response) {
+        if (item?.result === undefined || Number(item.result) === 0) {
+          continue;
+        }
+        output.push({ id: item.id, data: `0x${item.result.substring(26)}` });
+      }
+      return output;
+    }
+
+    async function eventLookup(rpc, contract) {
       const events = {
         'Upgraded(address)': '0xbc7cd75a20ee27fd9adebab32041f755214dbc6bffa90cc0225b39da2e5c2d3b',
         'BeaconUpgraded(address)': '0x1cf3b03a6cf19fa2baba4df148e9dcabedea7f8a5c07840e207e5c089be95d3e',
         'AdminChanged(address,address)': '0x7e644d79422f17c01e4894b5f4f588d331ebfa28653d42ae832dc59e38c9798f'
       }
+
+      const eventPayload = [];
       for (const [key, value] of Object.entries(events)) {
         eventPayload.push({
           jsonrpc: '2.0',
@@ -121,40 +134,41 @@
         });
       }
 
-      slotOutput.innerHTML = '';
-      eventOutput.innerHTML = '';
-
-      // Storage slot lookup
-      fetch(rpc, {
-        method: 'POST',
-        headers: { 'Content-Type': 'application/json' },
-        body: JSON.stringify(slotPayload)
-      })
-        .then(r => r.json())
-        .then(r => r.forEach(i => { Number(i.result) === 0 || slotOutput.insertAdjacentHTML('beforeend', `<p>${i.id}: 0x${i.result.substring(26)}</p>`) }));
-
-      // Event lookup
-      fetch(rpc, {
+      const response = await fetch(rpc, {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify(eventPayload)
-      })
-        .then(r => r.json())
-        .then(r => {
-          r.forEach(item => {
-            if (item?.result === undefined) {
-              return;
-            }
-            for (const log of item.result) {
-              if (log.data === '0x') { // Upgraded event (new address is indexed)
-                eventOutput.insertAdjacentHTML('beforeend', `<p>${item.id} (block ${Number(log.blockNumber)}): 0x${log.topics[1].substring(26)}</p>`);
-              }
-              else { // Admin changed event (new address is not indexed)
-                eventOutput.insertAdjacentHTML('beforeend', `<p>${item.id} (block ${Number(log.blockNumber)}): 0x${log.data.slice(-40)}</p>`);
-              }
-            }
-          });
-        });
+      }).then(r => r.json());
+
+      const output = [];
+      for (const item of response) {
+        if (item?.result === undefined) {
+          continue;
+        }
+        for (const log of item.result) {
+          if (log.data === '0x') { // Upgraded event (new address is indexed)
+            output.push({ id: item.id, blockNumber: Number(log.blockNumber), data: `0x${log.topics[1].substring(26)}` });
+          }
+          else { // Admin changed event (new address is not indexed)
+            output.push({ id: item.id, blockNumber: Number(log.blockNumber), data: `0x${log.data.slice(-40)}` });
+          }
+        }
+      }
+      return output;
+    };
+
+    document.querySelector('form').addEventListener('submit', e => {
+      e.preventDefault();
+      const contract = e.target.elements['contract'].value;
+      const rpc = e.target.elements['rpc'].value;
+      const slotOutput = e.target.elements['slot-output'];
+      const eventOutput = e.target.elements['event-output'];
+
+      slotOutput.innerHTML = '';
+      eventOutput.innerHTML = '';
+
+      slotLookup(rpc, contract).then(arr => arr.forEach(i => slotOutput.insertAdjacentHTML('beforeend', `<p>${i.id}: ${i.data}</p>`)));
+      eventLookup(rpc, contract).then(arr => arr.forEach(i => eventOutput.insertAdjacentHTML('beforeend', `<p>${i.id} (block ${i.blockNumber}): ${i.data}</p>`)));
     });
   </script>
 </body>