feat(weavedrive): add l2 header access to weavedrive

extensions/weavedrive/client/main.lua

@@ -45,4 +45,18 @@ function drive.getData(txId)
   return contents
 end
 
+function drive.getDataItem(txId)
+  local file = io.open('/txDataItem/' .. txId)
+  if not file then
+    return nil, "File not found!"
+  end
+  if file == 'GQL Not Found!' then
+    return nil, 'GraphQL not Found!'
+  end
+  local contents = file:read(
+    file:seek('end')
+  )
+  file:close()
+  return contents
+end
 return drive

extensions/weavedrive/src/index.js

@@ -127,7 +127,79 @@ module.exports = function weaveDrive(mod, FS) {
       var stream = FS.open('/tx/' + id, 'r');
       return stream;
     },
+    async createDataItemTxHeader(id) {
+      const gqlQuery = this.gqlQuery
+      async function toAddress(owner) {
+        return Arweave.utils.bufferTob64Url(
+          await Arweave.crypto.hash(Arweave.utils.b64UrlToBuffer(owner))
+        );
+      }
+      async function retry(x) {
+        return new Promise(r => {
+          setTimeout(function () {
+            r(gqlQuery(`/tx/${id}`))
+          }, x * 10000)
+        })
+      }
 
+      const gqlExists = this.gqlExists()
+      if (!gqlExists) {
+        return 'GQL Not Found!'
+      }
+      var GET_TRANSACTION_QUERY = `
+        query GetTransactions ($transactionIds: [ID!]!) {
+          transactions(ids: $transactionIds) {
+            edges {
+              node {
+                id
+                owner {
+                  address
+                }
+                quantity {
+                  winston
+                  ar
+                }
+                signature
+                tags {
+                  name
+                  value
+                }
+                block {
+                  id
+                  height
+                  timestamp
+                }
+                data {
+                  size
+                  type
+                }
+                bundledIn {
+                  id
+                }
+                fee {
+                  winston
+                  ar
+                }
+              }
+            }
+          }
+        }`
+      var variables = { transactionIds: [id] }
+      // todo: add a bunch of retries
+      var result = await this.gqlQuery(GET_TRANSACTION_QUERY, variables)
+        .then(res => !res.ok ? retry(1) : res)
+        .then(res => !res.ok ? retry(2) : res)
+        .then(res => !res.ok ? retry(3) : res)
+        .then(res => !res.ok ? retry(4) : res)
+        .then(res => res.data.transactions.edges[0].node)
+        .then(async entry => ({ ...entry, ownerAddress: await toAddress(entry.owner.address) }))
+        .then(x => JSON.stringify(x));
+
+        var node = FS.createDataFile('/', 'txDataItem/' + id, result, true, false);
+        var stream = FS.open('/txDataItem/' + id, 'r');
+
+        return stream;
+    },
     async open(filename) {
       const pathCategory = filename.split('/')[1];
       const id = filename.split('/')[2];
@@ -147,6 +219,20 @@ module.exports = function weaveDrive(mod, FS) {
         }
 
       }
+      if (pathCategory === 'txDataItem') {
+        FS.createPath('/', 'txDataItem', true, false);
+        if (FS.analyzePath(filename).exists) {
+          for (var i = 0; i < FS.streams.length; i++) {
+            if (FS.streams[i].node.name === id) {
+              return FS.streams[i].fd;
+            }
+          }
+          return 0;
+        } else {
+          const stream = await this.createDataItemTxHeader(id);
+          return stream.fd;
+        }
+      }
       if (pathCategory === 'block') {
         FS.createPath('/', 'block', true, false);
         if (FS.analyzePath(filename).exists) {
@@ -189,7 +275,6 @@ module.exports = function weaveDrive(mod, FS) {
         return 0;
       }
     },
-
     async read(fd, raw_dst_ptr, raw_length) {
 
       // Note: The length and dst_ptr are 53 bit integers in JS, so this _should_ be ok into a large memspace.
@@ -468,6 +553,28 @@ module.exports = function weaveDrive(mod, FS) {
       const results = await mod.arweave.api.post('/graphql', query);
       const json = JSON.parse(results)
       return json.data.transactions.edges.length > 0
+    },
+
+    async gqlExists() {
+      const query = `query {
+        transactions(
+          first: 1
+        ) {
+          pageInfo {
+            hasNextPage
+          }
+        }
+      }
+      `
+
+      const gqlExists = await mod.arweave.api.post('/graphql', query).then((res) => res.ok)
+      return gqlExists
+    },
+
+    async gqlQuery(query, variables) {
+      const results = await mod.arweave.api.post('/graphql', JSON.stringify({ query, variables }))
+      const json = JSON.parse(results)
+      return json
     }
   }
-}
+}