From 77bd30901db638833feca646fdb34f9434171462 Mon Sep 17 00:00:00 2001
From: Ian Norden <iannordenn@gmail.com>
Date: Wed, 17 Jun 2020 11:33:19 -0500
Subject: [PATCH] golint, add go report card

---
 README.md   | 9 ++++++++-
 batch.go    | 2 ++
 database.go | 5 ++++-
 iterator.go | 6 +++++-
 4 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index d0d9d9a..7a9dcf3 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,6 @@
 ## pg-ipfs-ethdb
 
+[![Go Report Card](https://goreportcard.com/badge/github.com/vulcanize/pg-ipfs-ethdb)](https://goreportcard.com/report/github.com/vulcanize/pg-ipfs-ethdb)
 
 > go-ethereum ethdb interfaces for Ethereum state data stored in Postgres-backed IPFS
 
@@ -29,6 +30,8 @@ with a few exceptions:
 package main
 
 import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/trie"
 	"github.com/jmoiron/sqlx"
 	"github.com/vulcanize/pg-ipfs-ethdb"
@@ -40,8 +43,12 @@ func main() {
 
     kvs := ipfsethdb.NewKeyValueStore(db)
     trieDB := trie.NewDatabase(kvs)
+    trie, _ := trie.New(common.Hash{}, trieDB)
+    // do stuff with trie or trieDB
 
-    // do stuff
+    database := ipfsethdb.NewDatabase(db)
+    statedb := state.NewDatabase(database)
+    // do stuff with the state database
 }
 ```
 
diff --git a/batch.go b/batch.go
index f90f52a..de7f14d 100644
--- a/batch.go
+++ b/batch.go
@@ -21,12 +21,14 @@ import (
 	"github.com/jmoiron/sqlx"
 )
 
+// Batch is the type that satisfies the ethdb.Batch interface for PG-IPFS Ethereum data
 type Batch struct {
 	db   *sqlx.DB
 	tx   *sqlx.Tx
 	size int
 }
 
+// NewBatch returns a ethdb.Batch interface for PG-IPFS
 func NewBatch(db *sqlx.DB) ethdb.Batch {
 	return &Batch{
 		db: db,
diff --git a/database.go b/database.go
index e8d9028..4ee318a 100644
--- a/database.go
+++ b/database.go
@@ -35,16 +35,19 @@ var (
 	dbSizePgStr = "SELECT pg_database_size(current_database())"
 )
 
+// Database is the type that satisfies the ethdb.Database and ethdb.KeyValueStore interfaces for PG-IPFS Ethereum data
 type Database struct {
 	db *sqlx.DB
 }
 
+// NewKeyValueStore returns a ethdb.KeyValueStore interface for PG-IPFS
 func NewKeyValueStore(db *sqlx.DB) ethdb.KeyValueStore {
 	return &Database{
 		db: db,
 	}
 }
 
+// NewDatabase returns a ethdb.Database interface for PG-IPFS
 func NewDatabase(db *sqlx.DB) ethdb.Database {
 	return &Database{
 		db: db,
@@ -190,7 +193,7 @@ func (d *Database) NewBatch() ethdb.Batch {
 // Note: This method assumes that the prefix is NOT part of the start, so there's
 // no need for the caller to prepend the prefix to the start
 func (d *Database) NewIterator(prefix []byte, start []byte) ethdb.Iterator {
-	return NewIterator([]byte{}, []byte{}, d.db)
+	return NewIterator(start, prefix, d.db)
 }
 
 // Close satisfies the io.Closer interface
diff --git a/iterator.go b/iterator.go
index 3336eeb..a1e45dd 100644
--- a/iterator.go
+++ b/iterator.go
@@ -21,14 +21,18 @@ import (
 	"github.com/jmoiron/sqlx"
 )
 
-// We don't need these iterator interfaces right now
+// Iterator is the type that satisfies the ethdb.Iterator interface for PG-IPFS Ethereum data
 // Iteratee interface is only used in Geth for various tests, trie/sync_bloom.go (for fast sync), and rawdb.InspectDatabase
+// Don't need this interface for the majority of state operations
+// This should not be confused with trie.NodeIterator or state.NodeIteraor (which can be constructed from the ethdb.KeyValueStore and ethdb.Database interfaces)
+// ethdb.KeyValueStore => trie.Database => trie.Trie => trie.NodeIterator
 type Iterator struct {
 	db                 *sqlx.DB
 	currentKey, prefix []byte
 	err                error
 }
 
+// NewIterator returns a ethdb.Iterator interface for PG-IPFS
 func NewIterator(start, prefix []byte, db *sqlx.DB) ethdb.Iterator {
 	return &Iterator{
 		db:         db,