CLI: add new -header option to be able to add headers to all cli requ…

…ests #8754

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

@@ -57,6 +57,8 @@ type BaseCommand struct {
 
 	flagMFA []string
 
+	flagHeader map[string]string
+
 	tokenHelper token.TokenHelper
 
 	client *api.Client
@@ -153,6 +155,12 @@ func (c *BaseCommand) Client() (*api.Client, error) {
 		client.SetPolicyOverride(c.flagPolicyOverride)
 	}
 
+	if c.flagHeader != nil {
+		for key, val := range c.flagHeader {
+			client.AddHeader(key, val)
+		}
+	}
+
 	c.client = client
 
 	return client, nil
@@ -356,6 +364,14 @@ func (c *BaseCommand) flagSet(bit FlagSetBit) *FlagSets {
 					"command string and exit.",
 			})
 
+			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. " +
+					"This can be specified multiple times.",
+			})
+
 		}
 
 		if bit&(FlagSetOutputField|FlagSetOutputFormat) != 0 {