feat(chain): Arweave integration

chain/arweave.ts

@@ -0,0 +1,69 @@
+import '../common/eager_offset'
+import { Bytes } from '../common/collections'
+
+// Most types from this namespace are direct mappings or adaptations from:
+// https://github.com/ChainSafe/firehose-arweave/blob/master/proto/sf/arweave/type/v1/type.proto
+export namespace arweave {
+  /**
+   * A key-value pair for arbitrary metadata
+   */
+  export class Tag {
+    constructor(public name: Bytes, public value: Bytes) {}
+  }
+
+  export class ProofOfAccess {
+    constructor(
+      public option: string,
+      public txPath: Bytes,
+      public dataPath: Bytes,
+      public chunk: Bytes,
+    ) {}
+  }
+
+  /**
+   * An Arweave block.
+   */
+  export class Block {
+    constructor(
+      public indepHash: Bytes,
+      public nonce: Bytes,
+      public previousBlock: Bytes,
+      public timestamp: u64,
+      public lastRetarget: u64,
+      public diff: string,
+      public height: u64,
+      public hash: Bytes,
+      public txRoot: Bytes,
+      public walletList: Bytes,
+      public rewardAddr: Bytes,
+      public tags: Tag[],
+      public rewardPool: string,
+      public weaveSize: string,
+      public blockSize: string,
+      public cumulativeDiff: string,
+      public hashList: Bytes,
+      public hashListMerkle: Bytes,
+      public poa: ProofOfAccess,
+    ) {}
+  }
+
+  /**
+   * An Arweave transaction
+   */
+  export class Transaction {
+    constructor(
+      public format: u32,
+      public id: string,
+      public lastTx: Bytes,
+      public owner: Bytes,
+      public tags: Tag[],
+      public target: Bytes,
+      public quantity: string,
+      public data: Bytes,
+      public dataSize: string,
+      public dataRoot: string,
+      public signature: Bytes,
+      public reward: string,
+    ) {}
+  }
+}