added docs and comments

db.go

@@ -2,6 +2,8 @@ package kvrepl
 
 import "fmt"
 
+// DB is struct defining two maps, pkv (points to kv) and nest, which
+// aids figuring out how nested the commits are for current transaction
 type DB struct {
 	KV1  map[string]string
 	KV2  map[string]string
@@ -9,6 +11,7 @@ type DB struct {
 	nest int
 }
 
+// read reads a key out of a map and checks for parsing errors
 func read(args []string, kv map[string]string) (string, error) {
 	if len(args) != 1 {
 		return "", fmt.Errorf("incorrect usage: READ <key>")
@@ -20,6 +23,7 @@ func read(args []string, kv map[string]string) (string, error) {
 	return i, nil
 }
 
+// write writes key/value to map and checks for parsing errors
 func write(args []string, kv map[string]string) error {
 	if len(args) != 2 {
 		return fmt.Errorf("incorrect usage: WRITE <key> <value>")
@@ -28,6 +32,7 @@ func write(args []string, kv map[string]string) error {
 	return nil
 }
 
+// del deletes a key from map and checks for parsing errors
 func del(args []string, kv map[string]string) error {
 	if len(args) != 1 {
 		return fmt.Errorf("incorrect usage: DELETE <key>")
@@ -40,6 +45,7 @@ func del(args []string, kv map[string]string) error {
 	return nil
 }
 
+// whichDB returns which db is currently being written to
 func whichDB(d *DB) map[string]string {
 	if d.PKV {
 		return d.KV1