Add doc to index blocks out of order using eth-statediff-service (#146)

* Add doc to index blocks using eth-statediff-service

* Add example commands and watcher queries

packages/mobymask-watcher/indexing.md

@@ -0,0 +1,218 @@
+# Index missing blocks with eth-statediff-service
+
+This readme can be followed to index required blocks out of order for a contract. This indexed data can then be used by the watcher further.
+
+* For indexing the required blocks the following core services will be used:
+
+  * [ipld-eth-db](https://github.com/vulcanize/ipld-eth-db)
+
+    * Run ipld-eth-db database using docker:
+
+      ```bash
+      docker-compose -f docker-compose.yml up
+      ```
+    
+  * [leveldb-ethdb-rpc](https://github.com/vulcanize/leveldb-ethdb-rpc)
+
+    It is an RPC wrapper around LevelDB. The endpoint can be used by eth-statediff-service to access LevelDB.
+
+  * [eth-statediff-service](https://github.com/vulcanize/eth-statediff-service)
+
+    * The [config file](https://github.com/vulcanize/eth-statediff-service/blob/sharding/environments/config.toml) can be updated with the following for running eth-statediff-service:
+
+      ```toml
+      [leveldb]
+        mode = "remote"
+        # leveldb-ethdb-rpc endpoint
+        url = "http://127.0.0.1:8082/"
+
+      [server]
+        httpPath = "0.0.0.0:8545"
+
+      [statediff]
+        prerun = false
+        serviceWorkers = 2
+        workerQueueSize = 1024
+        trieWorkers = 16
+
+      [log]
+        level = "info"
+
+      [database]
+        # Credentials for ipld-eth-db database
+        name     = "vulcanize_testing"
+        hostname = "localhost"
+        port     = 8077
+        user     = "vdbm"
+        password = "password"
+        type = "postgres"
+        driver = "sqlx"
+
+      [cache]
+        database = 1024
+        trie = 4096
+
+      [ethereum]
+        # Config for mainnet
+        nodeID = "1"
+        clientName = "eth-statediff-service"
+        networkID = 1
+        chainID = 1
+      ```
+
+    * Run eth-statediff-service:
+
+      ```bash
+      make build && ./eth-statediff-service serve --config environments/config.toml
+      ```
+  
+* Indexing required blocks can be done in the following way:
+
+  * Call `writeStateDiffAt` API with watched addresses for required blocks:
+
+    ```bash
+    # Replace $BLOCK_NUMBER with required block number to index and $CONTRACT_ADDRESS with the contract of interest.
+    curl -X POST -H 'Content-Type: application/json' --data '{"jsonrpc":"2.0","method":"statediff_writeStateDiffAt","params":[$BLOCK_NUMBER, {"intermediateStateNodes":true,"intermediateStorageNodes":true,"includeBlock":true,"includeReceipts":true,"includeTD":true,"includeCode":true,"watchedAddresses":["$CONTRACT_ADDRESS"]}],"id":1}' "127.0.0.1":"8545"
+    ```
+
+    Example for indexing [mainnet MobyMask blocks](https://etherscan.io/address/0xb06e6db9288324738f04fcaac910f5a60102c1f8):
+    - 14869713
+    - 14875233
+    - 14876405
+    - 14884873
+    - 14885755
+
+    ```bash
+    curl -X POST -H 'Content-Type: application/json' --data '{"jsonrpc":"2.0","method":"statediff_writeStateDiffAt","params":[14869713, {"intermediateStateNodes":true,"intermediateStorageNodes":true,"includeBlock":true,"includeReceipts":true,"includeTD":true,"includeCode":true,"watchedAddresses":["0xB06E6DB9288324738f04fCAAc910f5A60102C1F8"]}],"id":1}' "127.0.0.1":"8545"
+    ```
+
+    After successfully completing writeStateDiffAt for a block the returned response is:
+
+    ```bash
+    curl: (52) Empty reply from server
+    ```
+
+    **NOTE**: Using remote leveldb-ethdb-rpc takes long time (6-20 minutes).
+
+  * Stop the eth-statediff-service after all required blocks are indexed.
+
+* Start the [ipld-eth-server](https://github.com/vulcanize/eth-statediff-service) to query the indexed data from watcher.
+
+  * Create the following config.toml file for ipld-eth-server in [environments directory](https://github.com/vulcanize/ipld-eth-server/tree/sharding/environments):
+
+    ```toml
+    [database]
+      # Credentials for ipld-eth-db database
+      name     = "vulcanize_testing" # $DATABASE_NAME
+      hostname = "localhost" # $DATABASE_HOSTNAME
+      port     = 8077 # $DATABASE_PORT
+      user     = "vdbm" # $DATABASE_USER
+      password = "password" # $DATABASE_PASSWORD
+
+    [log]
+      level = "info" # $LOGRUS_LEVEL
+
+    [ethereum]
+      # Config for mainnet
+      chainID = "1" # $ETH_CHAIN_ID
+      nodeID = "arch1" # $ETH_NODE_ID
+      clientName = "Geth" # $ETH_CLIENT_NAME
+      networkID = "1" # $ETH_NETWORK_ID
+    ```
+  
+  * Run the server with the config above:
+
+    ```bash
+    make build && ./ipld-eth-server serve --config=./environments/config.toml --eth-server-graphql --log-level info
+    ```
+
+* The following steps are for indexing blocks out of order in the watcher:
+
+  * Follow [steps in the readme](./README.md#setup) to setup the watcher.
+
+  * Watch the contract:
+
+    ```bash
+    # Replace $CONTRACT_ADDRESS and $CONTRACT_NAME witch actual values
+    yarn watch:contract --address $CONTRACT_ADDRESS --kind $CONTRACT_NAME --checkpoint true
+    
+    # Example for mobymask-watcher
+    yarn watch:contract --address 0xB06E6DB9288324738f04fCAAc910f5A60102C1F8 --kind PhisherRegistry --checkpoint true
+    ```
+
+  * Index the required blocks. They should be the same blocks indexed by eth-statediff-service above.
+
+    ```bash
+    # Replace $BLOCK_NUMBER with required block number to index
+    yarn index-block --block $BLOCK_NUMBER
+    ```
+
+    Example for [mainnet MobyMask blocks](https://etherscan.io/address/0xb06e6db9288324738f04fcaac910f5a60102c1f8) indexed above:
+    ```bash
+    yarn index-block --block 14869713
+    ```
+  
+  * Check the `event` and `block_progress` table to confirm that the required blocks have been indexed properly.
+
+* The watcher can be started to perform queries on the indexed data:
+  
+  * The watcher can be started in lazy mode:
+
+    * Update `server.kind` in [config](./environments/local.toml):
+
+      ```toml
+      [server]
+        kind = "lazy"
+      ```
+
+    * Run server:
+
+      ```bash
+      yarn server
+      ```
+
+  * Run query in [GraphQL endpoint](http://127.0.0.1:3010/graphql) to get events in a range. Following query is for getting events in the range of mainnet blocks indexed for mobymask-watcher:
+
+    ```graphql
+    query {
+      eventsInRange(
+        # Range for mainnet data blocks
+        fromBlockNumber: 14869713
+        toBlockNumber: 14885755
+      ) {
+        block {
+          hash
+          number
+        }
+        tx {
+          hash
+        }
+        contract
+        eventIndex
+        event {
+          __typename
+        }
+        proof {
+          data
+        }
+      }
+    }
+    ```
+
+  * Run query to get contract storage variable values. The following query is for getting value of `isMember` variable in MobyMask contract:
+
+    ```graphql
+    query {
+      isMember(
+        # BlockHash of an indexed mainnet block that can be taken from the events returned above
+        blockHash: "0x28cb16e740cd5d7de869bee2957e7442790e9d774e6e71804a67933c7e628038"
+        contractAddress: "0xB06E6DB9288324738f04fCAAc910f5A60102C1F8"
+        key0: "TWT:danfinlay"
+      ) {
+        value
+        proof {
+          data
+        }
+      }
+    }
+    ```