From b92c0ef80686bedf0aeda64271bf5e734fdce751 Mon Sep 17 00:00:00 2001
From: Alex Normand <alex.normand@datadoghq.com>
Date: Fri, 10 Jun 2022 12:10:59 -0700
Subject: [PATCH] Make SQLCommentInjection mode a string

---
 contrib/database/sql/option.go |  3 ++-
 contrib/database/sql/sql.go    |  4 ++--
 ddtrace/tracer/sqlcomment.go   | 12 ++++++++----
 3 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/contrib/database/sql/option.go b/contrib/database/sql/option.go
index 1861549c61..ca887772f1 100644
--- a/contrib/database/sql/option.go
+++ b/contrib/database/sql/option.go
@@ -7,6 +7,7 @@ package sql
 
 import (
 	"math"
+	"os"
 
 	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
 	"gopkg.in/DataDog/dd-trace-go.v1/internal"
@@ -36,7 +37,7 @@ func defaults(cfg *config) {
 	} else {
 		cfg.analyticsRate = math.NaN()
 	}
-	cfg.commentInjectionMode = tracer.SQLCommentInjectionMode(internal.IntEnv("DD_TRACE_SQL_COMMENT_INJECTION_MODE", int(tracer.SQLInjectionDisabled)))
+	cfg.commentInjectionMode = tracer.SQLCommentInjectionMode(os.Getenv("DD_TRACE_SQL_COMMENT_INJECTION_MODE"))
 }
 
 // WithServiceName sets the given service name when registering a driver,
diff --git a/contrib/database/sql/sql.go b/contrib/database/sql/sql.go
index 857d768093..1c23d22858 100644
--- a/contrib/database/sql/sql.go
+++ b/contrib/database/sql/sql.go
@@ -21,12 +21,12 @@ import (
 	"database/sql"
 	"database/sql/driver"
 	"errors"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
 	"math"
 	"reflect"
 	"time"
 
 	"gopkg.in/DataDog/dd-trace-go.v1/contrib/database/sql/internal"
-	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
 	"gopkg.in/DataDog/dd-trace-go.v1/internal/log"
 )
 
@@ -187,7 +187,7 @@ func OpenDB(c driver.Connector, opts ...Option) *sql.DB {
 	if math.IsNaN(cfg.analyticsRate) {
 		cfg.analyticsRate = rc.analyticsRate
 	}
-	if cfg.commentInjectionMode == tracer.SQLInjectionDisabled {
+	if cfg.commentInjectionMode == tracer.SQLInjectionUndefined {
 		cfg.commentInjectionMode = rc.commentInjectionMode
 	}
 	cfg.childSpansOnly = rc.childSpansOnly
diff --git a/ddtrace/tracer/sqlcomment.go b/ddtrace/tracer/sqlcomment.go
index 97cc7dc303..05cd0263da 100644
--- a/ddtrace/tracer/sqlcomment.go
+++ b/ddtrace/tracer/sqlcomment.go
@@ -15,15 +15,17 @@ import (
 )
 
 // SQLCommentInjectionMode represents the mode of SQL comment injection.
-type SQLCommentInjectionMode int
+type SQLCommentInjectionMode string
 
 const (
+	// SQLInjectionUndefined represents the comment injection mode is not set. This is the same as SQLInjectionDisabled.
+	SQLInjectionUndefined SQLCommentInjectionMode = ""
 	// SQLInjectionDisabled represents the comment injection mode where all injection is disabled.
-	SQLInjectionDisabled SQLCommentInjectionMode = 0
+	SQLInjectionDisabled SQLCommentInjectionMode = "disabled"
 	// SQLInjectionModeService represents the comment injection mode where only service tags (name, env, version) are injected.
-	SQLInjectionModeService SQLCommentInjectionMode = 1
+	SQLInjectionModeService SQLCommentInjectionMode = "service"
 	// SQLInjectionModeFull represents the comment injection mode where both service tags and tracing tags. Tracing tags include span id, trace id and sampling priority.
-	SQLInjectionModeFull SQLCommentInjectionMode = 2
+	SQLInjectionModeFull SQLCommentInjectionMode = "full"
 )
 
 // Key names for SQL comment tags.
@@ -50,6 +52,8 @@ func (c *SQLCommentCarrier) Inject(spanCtx ddtrace.SpanContext) error {
 	c.SpanID = random.Uint64()
 	tags := make(map[string]string)
 	switch c.Mode {
+	case SQLInjectionUndefined:
+		fallthrough
 	case SQLInjectionDisabled:
 		return nil
 	case SQLInjectionModeFull: