libs/common: refactor libs/common 2 (#4231)

* libs/common: refactor libs/common 2

- move random function to there own pkg

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

* change imports and usage throughout repo

* fix goimports

* add changelog entry

rpc/client/event_test.go

@@ -9,7 +9,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	abci "github.com/tendermint/tendermint/abci/types"
-	cmn "github.com/tendermint/tendermint/libs/common"
+	"github.com/tendermint/tendermint/libs/rand"
 	"github.com/tendermint/tendermint/rpc/client"
 	ctypes "github.com/tendermint/tendermint/rpc/core/types"
 	"github.com/tendermint/tendermint/types"
@@ -19,8 +19,8 @@ var waitForEventTimeout = 5 * time.Second
 
 // MakeTxKV returns a text transaction, allong with expected key, value pair
 func MakeTxKV() ([]byte, []byte, []byte) {
-	k := []byte(cmn.RandStr(8))
-	v := []byte(cmn.RandStr(8))
+	k := []byte(rand.RandStr(8))
+	v := []byte(rand.RandStr(8))
 	return k, v, append(k, append([]byte("="), v...)...)
 }
 

rpc/lib/client/ws_client.go

@@ -15,6 +15,7 @@ import (
 
 	amino "github.com/tendermint/go-amino"
 	cmn "github.com/tendermint/tendermint/libs/common"
+	"github.com/tendermint/tendermint/libs/rand"
 	types "github.com/tendermint/tendermint/rpc/lib/types"
 )
 
@@ -288,7 +289,7 @@ func (c *WSClient) reconnect() error {
 	}()
 
 	for {
-		jitterSeconds := time.Duration(cmn.RandFloat64() * float64(time.Second)) // 1s == (1e9 ns)
+		jitterSeconds := time.Duration(rand.RandFloat64() * float64(time.Second)) // 1s == (1e9 ns)
 		backoffDuration := jitterSeconds + ((1 << uint(attempt)) * time.Second)
 
 		c.Logger.Info("reconnecting", "attempt", attempt+1, "backoff_duration", backoffDuration)

rpc/lib/rpc_test.go

@@ -19,6 +19,7 @@ import (
 	amino "github.com/tendermint/go-amino"
 	cmn "github.com/tendermint/tendermint/libs/common"
 	"github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/libs/rand"
 
 	client "github.com/tendermint/tendermint/rpc/lib/client"
 	server "github.com/tendermint/tendermint/rpc/lib/server"
@@ -206,7 +207,7 @@ func testWithHTTPClient(t *testing.T, cl client.HTTPClient) {
 	require.Nil(t, err)
 	assert.Equal(t, got3, val3)
 
-	val4 := cmn.RandIntn(10000)
+	val4 := rand.RandIntn(10000)
 	got4, err := echoIntViaHTTP(cl, val4)
 	require.Nil(t, err)
 	assert.Equal(t, got4, val4)
@@ -370,7 +371,7 @@ func TestWSClientPingPong(t *testing.T) {
 }
 
 func randBytes(t *testing.T) []byte {
-	n := cmn.RandIntn(10) + 2
+	n := rand.RandIntn(10) + 2
 	buf := make([]byte, n)
 	_, err := crand.Read(buf)
 	require.Nil(t, err)