CLI: add new -header option to be able to add headers to all cli http request

changelog/12508.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+cli: add new http option : -header which enable sending arbitrary headers with the cli
+```

command/base.go

@@ -58,6 +58,8 @@ type BaseCommand struct {
 
 	flagMFA []string
 
+	flagHeader map[string]string
+
 	tokenHelper token.TokenHelper
 
 	client *api.Client
@@ -154,6 +156,23 @@ func (c *BaseCommand) Client() (*api.Client, error) {
 		client.SetPolicyOverride(c.flagPolicyOverride)
 	}
 
+	if c.flagHeader != nil {
+
+		var forbiddenHeaders []string
+		for key, val := range c.flagHeader {
+
+			if strings.HasPrefix(key, "X-Vault-") {
+				forbiddenHeaders = append(forbiddenHeaders, key)
+				continue
+			}
+			client.AddHeader(key, val)
+		}
+
+		if len(forbiddenHeaders) > 0 {
+			return nil, fmt.Errorf("failed to setup Headers[%s]: Header starting by 'X-Vault-' are for internal usage only", strings.Join(forbiddenHeaders, ", "))
+		}
+	}
+
 	c.client = client
 
 	return client, nil
@@ -365,6 +384,15 @@ func (c *BaseCommand) flagSet(bit FlagSetBit) *FlagSets {
 				Usage:      "Key to unlock a namespace API lock.",
 			})
 
+			f.StringMapVar(&StringMapVar{
+				Name:       "header",
+				Target:     &c.flagHeader,
+				Completion: complete.PredictAnything,
+				Usage: "Key-value pair provided as key=value to provide http header added to any request done by the CLI." +
+					"Trying to add headers starting with 'X-Vault-' is forbidden and will make the command fail " +
+					"This can be specified multiple times.",
+			})
+
 		}
 
 		if bit&(FlagSetOutputField|FlagSetOutputFormat) != 0 {

command/base_test.go

@@ -0,0 +1,69 @@
+package command
+
+import (
+	"net/http"
+	"reflect"
+	"testing"
+)
+
+func getDefaultCliHeaders(t *testing.T) http.Header {
+	bc := &BaseCommand{}
+	cli, err := bc.Client()
+	if err != nil {
+		t.Fatal(err)
+	}
+	return cli.Headers()
+}
+
+func TestClient_FlagHeader(t *testing.T) {
+	defaultHeaders := getDefaultCliHeaders(t)
+
+	cases := []struct {
+		Input map[string]string
+		Valid bool
+	}{
+		{
+			map[string]string{},
+			true,
+		},
+		{
+			map[string]string{"foo": "bar", "header2": "value2"},
+			true,
+		},
+		{
+			map[string]string{"X-Vault-foo": "bar", "header2": "value2"},
+			false,
+		},
+	}
+
+	for _, tc := range cases {
+		expectedHeaders := defaultHeaders.Clone()
+		for key, val := range tc.Input {
+			expectedHeaders.Add(key, val)
+		}
+
+		bc := &BaseCommand{flagHeader: tc.Input}
+		cli, err := bc.Client()
+
+		if err == nil && !tc.Valid {
+			t.Errorf("No error for input[%#v], but not valid", tc.Input)
+			continue
+		}
+
+		if err != nil {
+			if tc.Valid {
+				t.Errorf("Error[%v] with input[%#v], but valid", err, tc.Input)
+			}
+			continue
+		}
+
+		if cli == nil {
+			t.Error("client should not be nil")
+		}
+
+		actualHeaders := cli.Headers()
+		if !reflect.DeepEqual(expectedHeaders, actualHeaders) {
+			t.Errorf("expected [%#v] but got [%#v]", expectedHeaders, actualHeaders)
+		}
+	}
+}