feat(indexer): introduce indexer

.gitignore

@@ -13,3 +13,7 @@ out/
 ethereum/broadcast
 
 .env
+.DS_Store
+
+node_modules/
+indexer/lib/

indexer/.dockerignore

@@ -0,0 +1,8 @@
+/.git
+/node_modules
+/lib
+/*Versions.json
+npm-debug.log
+
+# OS Files
+.DS_Store

indexer/.squidignore

@@ -0,0 +1,7 @@
+node_modules
+builds
+lib
+Dockerfile
+.git
+.github
+.idea

indexer/README.md

@@ -0,0 +1,43 @@
+# Multichain transfers squid
+
+This [squid](https://docs.subsquid.io/) captures USDC Transfer events on ETH and BSC, stores them in the same database and serves the data over a common GraphQL API.
+
+The Ethereum processor is located in `src/eth` and similarly the Binance Chain processor can be found in `src/bsc`. The scripts file `commands.json` was updated with the commands `process:eth` and `process:bsc` to run the processors. 
+
+You can find some useful hints on developing multichain squids on the [dedicated documentation page](https://docs.subsquid.io/basics/multichain/).
+
+Dependencies: Node.js, Docker, Git.
+
+## Quickstart
+
+```bash
+# 0. Install @subsquid/cli a.k.a. the sqd command globally
+npm i -g @subsquid/cli
+
+# 1. Clone the repo
+git clone https://github.com/subsquid-labs/multichain-transfers-example
+cd multichain-transfers-example
+
+# 2. Install dependencies
+npm ci
+
+# 3. Start a Postgres database container and detach
+sqd up
+
+# 4. Apply the migration
+sqd migration:apply
+
+# 5. Build the squid
+sqd build
+
+# 6. Run all services at once
+sqd run .
+```
+A GraphiQL playground will be available at [localhost:4350/graphql](http://localhost:4350/graphql).
+
+You can also run individual services separately:
+```bash
+sqd process:eth # Ethereum processor
+sqd process:bsc # BSC processor
+sqd serve       # GraphQL server
+```

indexer/assets/IERC20Treasury.json

@@ -0,0 +1,78 @@
+[
+  {
+    "type": "event",
+    "name": "Deposit",
+    "inputs": [
+      {
+        "name": "from",
+        "type": "address",
+        "indexed": true,
+        "internalType": "address"
+      },
+      {
+        "name": "to",
+        "type": "bytes32",
+        "indexed": true,
+        "internalType": "bytes32"
+      },
+      {
+        "name": "token",
+        "type": "address",
+        "indexed": true,
+        "internalType": "address"
+      },
+      {
+        "name": "amount",
+        "type": "uint256",
+        "indexed": false,
+        "internalType": "uint256"
+      }
+    ],
+    "anonymous": false
+  },
+  {
+    "type": "event",
+    "name": "Withdraw",
+    "inputs": [
+      {
+        "name": "to",
+        "type": "address",
+        "indexed": true,
+        "internalType": "address"
+      },
+      {
+        "name": "token",
+        "type": "address",
+        "indexed": true,
+        "internalType": "address"
+      },
+      {
+        "name": "amount",
+        "type": "uint256",
+        "indexed": false,
+        "internalType": "uint256"
+      }
+    ],
+    "anonymous": false
+  },
+  {
+    "type": "error",
+    "name": "BadArguments",
+    "inputs": []
+  },
+  {
+    "type": "error",
+    "name": "BadEthAddress",
+    "inputs": []
+  },
+  {
+    "type": "error",
+    "name": "BadVaraAddress",
+    "inputs": []
+  },
+  {
+    "type": "error",
+    "name": "NotAuthorized",
+    "inputs": []
+  }
+]

indexer/assets/IMessageQueue.json

@@ -0,0 +1,179 @@
+[
+  {
+    "type": "function",
+    "name": "calculateMerkleRoot",
+    "inputs": [
+      {
+        "name": "proof",
+        "type": "bytes32[]",
+        "internalType": "bytes32[]"
+      },
+      {
+        "name": "hash",
+        "type": "bytes32",
+        "internalType": "bytes32"
+      },
+      {
+        "name": "width",
+        "type": "uint256",
+        "internalType": "uint256"
+      },
+      {
+        "name": "leaf_index",
+        "type": "uint256",
+        "internalType": "uint256"
+      }
+    ],
+    "outputs": [
+      {
+        "name": "",
+        "type": "bytes32",
+        "internalType": "bytes32"
+      }
+    ],
+    "stateMutability": "view"
+  },
+  {
+    "type": "function",
+    "name": "processMessage",
+    "inputs": [
+      {
+        "name": "block_number",
+        "type": "uint256",
+        "internalType": "uint256"
+      },
+      {
+        "name": "total_leaves",
+        "type": "uint256",
+        "internalType": "uint256"
+      },
+      {
+        "name": "leaf_index",
+        "type": "uint256",
+        "internalType": "uint256"
+      },
+      {
+        "name": "message",
+        "type": "tuple",
+        "internalType": "struct VaraMessage",
+        "components": [
+          {
+            "name": "nonce",
+            "type": "bytes32",
+            "internalType": "bytes32"
+          },
+          {
+            "name": "sender",
+            "type": "bytes32",
+            "internalType": "bytes32"
+          },
+          {
+            "name": "receiver",
+            "type": "address",
+            "internalType": "address"
+          },
+          {
+            "name": "data",
+            "type": "bytes",
+            "internalType": "bytes"
+          }
+        ]
+      },
+      {
+        "name": "proof",
+        "type": "bytes32[]",
+        "internalType": "bytes32[]"
+      }
+    ],
+    "outputs": [],
+    "stateMutability": "nonpayable"
+  },
+  {
+    "type": "event",
+    "name": "MessageProcessed",
+    "inputs": [
+      {
+        "name": "blockNumber",
+        "type": "uint256",
+        "indexed": true,
+        "internalType": "uint256"
+      },
+      {
+        "name": "messageHash",
+        "type": "bytes32",
+        "indexed": true,
+        "internalType": "bytes32"
+      },
+      {
+        "name": "messageNonce",
+        "type": "bytes32",
+        "indexed": true,
+        "internalType": "bytes32"
+      }
+    ],
+    "anonymous": false
+  },
+  {
+    "type": "event",
+    "name": "ProoverAddressUpdated",
+    "inputs": [
+      {
+        "name": "proover",
+        "type": "address",
+        "indexed": false,
+        "internalType": "address"
+      }
+    ],
+    "anonymous": false
+  },
+  {
+    "type": "event",
+    "name": "RelayerAddressUpdated",
+    "inputs": [
+      {
+        "name": "relayer",
+        "type": "address",
+        "indexed": false,
+        "internalType": "address"
+      }
+    ],
+    "anonymous": false
+  },
+  {
+    "type": "error",
+    "name": "AlreadyInitialized",
+    "inputs": []
+  },
+  {
+    "type": "error",
+    "name": "BadProof",
+    "inputs": []
+  },
+  {
+    "type": "error",
+    "name": "MerkleRootNotSet",
+    "inputs": [
+      {
+        "name": "blockNumber",
+        "type": "uint256",
+        "internalType": "uint256"
+      }
+    ]
+  },
+  {
+    "type": "error",
+    "name": "MessageAlreadyProcessed",
+    "inputs": [
+      {
+        "name": "messageNonce",
+        "type": "bytes32",
+        "internalType": "bytes32"
+      }
+    ]
+  },
+  {
+    "type": "error",
+    "name": "MessageNotProcessed",
+    "inputs": []
+  }
+]