added comments

wait/sql.go

@@ -8,10 +8,11 @@ import (
 	"time"
 )
 
+//ForSQL constructs a new waitForSql strategy for the given driver
 func ForSQL(port nat.Port, driver string, url func(nat.Port) string) *waitForSql {
 	return &waitForSql{
-		Port: port,
-		URL: url,
+		Port:   port,
+		URL:    url,
 		Driver: driver,
 	}
 }
@@ -23,14 +24,17 @@ type waitForSql struct {
 	startupTimeout time.Duration
 }
 
+//Timeout sets the maximum waiting time for the strategy after which it'll give up and return an error
 func (w *waitForSql) Timeout(duration time.Duration) *waitForSql {
 	w.startupTimeout = duration
 	return w
 }
 
+//WaitUntilReady repeatedly tries to run "SELECT 1" query on the given port using sql and driver.
+// If the it doesn't succeed until the timeout value which defaults to 10 seconds, it will return an error
 func (w *waitForSql) WaitUntilReady(ctx context.Context, target StrategyTarget) (err error) {
 	if w.startupTimeout == 0 {
-		w.startupTimeout = time.Second*10
+		w.startupTimeout = time.Second * 10
 	}
 	ctx, cancel := context.WithTimeout(ctx, w.startupTimeout)
 	defer cancel()
@@ -60,4 +64,3 @@ func (w *waitForSql) WaitUntilReady(ctx context.Context, target StrategyTarget)
 		}
 	}
 }
-