Downloadable list of checkpoints (#91)

* (feat) Auto-generate checkpoints

* (fix) Fix URL for checkpoints

* (fix) Lint

* (fix) Fix message when there are no checkpoints.

* (feat) Prototestnet and protomainnet checkpoint download tables

MAGIC.md

@@ -0,0 +1,19 @@
+# Magic extra javascript stuff
+
+There is some javascript specified in the mkdocs control file
+and stored in `zq2/docs/js` which provides some extra facilities:
+
+## Checkpoints
+
+If you write:
+
+```html
+<div
+ class="zq2_checkpoints"
+ list="<somewhere_to_get_a_list_from>"
+ api="API entrypoint"
+ number=<nr>
+/>
+```
+
+Then `checkpoints.js` will generate a table inside your div of the last `nr` checkpoints.

zq2/docs/js/checkpoints.js

@@ -0,0 +1,96 @@
+function humanSize(inBytes) {
+  const NAMES = [ "KiB", "MiB", "GiB", "TiB" ];
+  let minSize = 1000;
+  let bestYet = null;
+  for (let i = 0;i < NAMES.length; ++i) {
+    let reportAs = inBytes / minSize;
+    // The replace is horrid - sorry!
+    bestYet = reportAs.toFixed(2).replace(".00", "") + " " + NAMES[i];
+    minSize = minSize * 1000;
+    if (reportAs < 1000) {
+      return bestYet;
+    }
+  }
+  return reportAs;
+}
+
+async function getBlockHash(apiUrl, block) {
+  const hexBlock = `0x${block.toString(16)}`;
+  var data = {
+    id: "1",
+    jsonrpc: "2.0",
+    method: "eth_getBlockByNumber",
+    params: [ hexBlock, false ]
+  };
+  return fetch(apiUrl, {
+    method: "POST",
+    headers: { "Content-Type": "application/json", },
+    body: JSON.stringify(data) })
+    .then((response) => response.json())
+    .then((data) => {
+      return data.result.hash
+    });
+}
+
+async function generateTableRow(apiUrl, baseUrl, value) {
+  // Find the block hash
+  return getBlockHash(apiUrl, value.block).then(
+    (h) => {
+      return `<tr><td><a href="${baseUrl}/${value.key}">${value.block}</a></td><td>${h}</td><td>${humanSize(value.size)}</td></tr>`;
+    });
+}
+
+async function fillCheckpointTableFromElem(elem) {
+  const listUrl = elem.getAttribute("list");
+  const apiUrl = elem.getAttribute("api");
+  const nrCheckpoints = elem.getAttribute("number");
+  // Get the list of checkpoints.
+  let inner = fetch(listUrl).then((data) =>
+    {
+      parser = new DOMParser();
+      data.text().then((docText) => {
+        xmlDoc = parser.parseFromString(docText, "text/xml");
+        sortedCheckpoints = []
+        var checkpoints = xmlDoc.getElementsByTagName("Contents");
+        for (let i = 0;i < checkpoints.length; ++i) {
+          let c = checkpoints[i];
+          let key = c.getElementsByTagName("Key")[0].textContent;
+          let size = c.getElementsByTagName("Size")[0].textContent;
+          // Now we need the block number.
+          let block = null;
+          if (key.startsWith("previous/")) {
+            block = parseInt(key.substring(10))
+          } else {
+            block = parseInt(key)
+          }
+          sortedCheckpoints.push({ key, block, size })
+        }
+        sortedCheckpoints.sort( (a,b) => b.block - a.block );
+        const sliced = sortedCheckpoints.slice(0, nrCheckpoints);
+        if (sliced.length > 0) {
+          const promises = sliced.map( (v) => generateTableRow(apiUrl, listUrl, v) );
+          Promise.all(promises).then((values) => {
+            const tableContents = values.reduce( (acc,v) => acc + v, "")
+            const tableHeader = "<tr>" +
+                  "<th>Checkpoint</th>" +
+                  "<th>Hash</th>" +
+                  "<th>Size</th>" +
+                  "</tr>";
+            elem.innerHTML = "<table>" + tableHeader + tableContents + "</table>";
+          });
+        } else {
+          elem.innerHTML = '<p><i>There are no checkpoints currently stored for this network</i></p>';
+        } })
+    }
+  );
+}
+
+
+function fillInCheckpoints() {
+  var ids = document.getElementsByClassName("zq2_checkpoints");
+  for (let i =0 ; i < ids.length; ++i) {
+    fillCheckpointTableFromElem(ids[i])
+  }
+}
+
+document$.subscribe( () => fillInCheckpoints() );

zq2/docs/nodes/checkpoints/download.md

@@ -0,0 +1,20 @@
+---
+id: nodes/checkpoints/download
+title: Download checkpoints
+---
+
+# Prototestnet checkpoints
+
+<div class="zq2_checkpoints" list="https://checkpoints.zq2-prototestnet.zilliqa.com/" api="https://api.zq2-prototestnet.zilliqa.com" number=4 >
+Loading; please wait ..
+</div>
+<p></p>
+
+# Protomainnet checkpoints
+
+<div class="zq2_checkpoints" list="https://checkpoints.zq2-protomainnet.zilliqa.com/" api="https://api.zq2-protomainnet.zilliqa.com" number=4 >
+Loading; please wait ..
+</div>
+
+
+

zq2/docs/nodes/checkpoint.md → zq2/docs/nodes/checkpoints/index.md

@@ -7,6 +7,8 @@ title: Checkpoint
 
 Checkpoints in nodes serve as specific reference points within the blockchain, allowing nodes to synchronize more efficiently when joining or rejoining the network. Instead of processing the entire blockchain from the genesis block, nodes can start from a known, validated state. Below is a detailed guide on how to set up checkpoints.
 
+You can find a list of checkpoints and hashes to download in the menu bar.
+
 ## Syncing a Node from a Checkpoint
 
 Before proceeding, ensure you have completed the [Node Setup](../nodes/node.md#setting-up-your-node) section.

zq2/mkdocs.in.yaml

@@ -6,7 +6,9 @@ nav:
   - Nodes & Validators:
       - Overview: nodes/index.md
       - Nodes: nodes/node.md
-      - Checkpoints: nodes/checkpoint.md
+      - Checkpoints:
+          - nodes/checkpoints/index.md
+          - Downloads: nodes/checkpoints/download.md
       - Node FAQ: nodes/nodefaq.md
       - Validator Monitoring: nodes/validatormonitoring.md
   - Tools and SDKs: sdk.md

zq2/parent.yaml

@@ -9,13 +9,13 @@ extra_css:
 
 extra_javascript:
   - js/versions.js
+  - js/checkpoints.js
   - js/connect.js
   - js/chain.js
   - js/buffer.js
   - js/add-zilliqa-PM-chain.js
   - js/add-zilliqa-PT-chain.js
 
-
 theme:
   name: material
   logo: assets/zilliqa.svg