Add authorization code credential flow to get token

sdk/azidentity/authorization_code_credential.go

@@ -0,0 +1,68 @@
+package azidentity
+
+import (
+	"context"
+	"github.com/Azure/azure-sdk-for-go/sdk/azcore"
+	"github.com/Azure/azure-sdk-for-go/sdk/azcore/policy"
+	"github.com/AzureAD/microsoft-authentication-library-for-go/apps/confidential"
+)
+
+const credNameAuthCode = "AuthorizationCodeCredential"
+
+type AuthorizationCodeCredentialOptions struct {
+	azcore.ClientOptions
+
+	TenantID     string
+	ClientID     string
+	ClientSecret string
+	AuthCode     string
+	RedirectURI  string
+}
+
+type AuthorizationCodeCredential struct {
+	options AuthorizationCodeCredentialOptions
+	client  confidentialClient
+	account confidential.Account
+	syncer  *syncer
+}
+
+func NewAuthorizationCodeCredential(options *AuthorizationCodeCredentialOptions) (*AuthorizationCodeCredential, error) {
+	if options == nil {
+		options = &AuthorizationCodeCredentialOptions{}
+	}
+
+	cred, err := confidential.NewCredFromSecret(options.ClientSecret)
+	if err != nil {
+		return nil, err
+	}
+
+	client, err := getConfidentialClient(options.ClientID, options.TenantID, cred, &options.ClientOptions)
+	if err != nil {
+		return nil, err
+	}
+
+	credential := &AuthorizationCodeCredential{
+		options: *options,
+		client:  client,
+	}
+	credential.syncer = newSyncer(credNameAuthCode, options.TenantID, []string{}, credential.requestToken, credential.silentAuth)
+
+	return credential, nil
+}
+
+func (c *AuthorizationCodeCredential) GetToken(ctx context.Context, opts policy.TokenRequestOptions) (azcore.AccessToken, error) {
+	return c.syncer.GetToken(ctx, opts)
+}
+
+func (c *AuthorizationCodeCredential) silentAuth(ctx context.Context, opts policy.TokenRequestOptions) (azcore.AccessToken, error) {
+	res, err := c.client.AcquireTokenSilent(ctx, opts.Scopes, confidential.WithSilentAccount(c.account))
+	return azcore.AccessToken{Token: res.AccessToken, ExpiresOn: res.ExpiresOn.UTC()}, err
+}
+
+func (c *AuthorizationCodeCredential) requestToken(ctx context.Context, opts policy.TokenRequestOptions) (azcore.AccessToken, error) {
+	res, err := c.client.AcquireTokenByAuthCode(ctx, c.options.AuthCode, c.options.RedirectURI, opts.Scopes)
+	c.account = res.Account
+	return azcore.AccessToken{Token: res.AccessToken, ExpiresOn: res.ExpiresOn.UTC()}, err
+}
+
+var _ azcore.TokenCredential = (*AuthorizationCodeCredential)(nil)