SetRequestCallbacks not working

[joseph-reslv]

Expected Behavior

When using SetRequestCallbacks, i expected the callbacks should be set to the requestCallbacks in client.

client.SetRequestCallbacks(func(req *http.Request) {
    fmt.Println("client callback")
})

Current Behavior

The requestCallbacks in client is still empty.

I think the reason the requestCallbacks not being copy is due to the copy function.

vault-client-go/request_modifiers.go

Line 173 in fd98162

func (c *Client) SetRequestCallbacks(callbacks ...RequestCallback) error {

// SetRequestCallbacks sets callbacks which will be invoked before each request.
func (c *Client) SetRequestCallbacks(callbacks ...RequestCallback) error {
	c.clientRequestModifiersLock.Lock()
	copy(c.clientRequestModifiers.requestCallbacks, callbacks)
	c.clientRequestModifiersLock.Unlock()

	return nil
}

As mentioned in the Copy,

Copy returns the number of elements copied, which will be the minimum of len(src) and len(dst).

So, when the client is initialized as no requestCallbacks, the copy function will always copy nothing to the requestCallbacks.

To solve the bug, I think you can change to use append to fix it.

c.clientRequestModifiers.requestCallbacks = append(c.clientRequestModifiers.requestCallbacks, callbacks...)

Failure Information

vault-client-go: 0.4.1

Please include the version of Vault binary and the version of vault-client-go you're using.

Steps to Reproduce

Please provide detailed steps for reproducing the issue.

client, _ := vault.New()

client.SetRequestCallbacks(func(req *http.Request) {
    fmt.Println("client callback")
})

Additional Information

I think the SetResponseCallbacks having same issue.

vault-client-go/request_modifiers.go

Line 190 in fd98162

func (c *Client) SetResponseCallbacks(callbacks ...ResponseCallback) error {

[averche]

Thanks for reporting this, @joseph-reslv! This is indeed an issue that somehow got overlooked, I'm fixing it in #242.