我找到了解決方案。我們可以通過刷新令牌來檢查令牌是否有效。如果刷新導致錯誤，則令牌不再有效。如果刷新成功，令牌將再有效一個小時。
因此，我們向后端添加了（可重用的）函數以使用https://directline.botframework.com/v3/directline/tokens/refresh. 我們更改了前端代碼以調用我們新的刷新功能。
前端代碼：
// Gets a new token from the cloud.
async function requestToken() {
if (!sessionStorage['webchatToken']) {
const res = await fetch('https://' + serviceName + '.azurewebsites.net/api/token');
// If the request was succesfull, store the token and userId.
if (res.status == 200) {
const jsonResult = await res.json();
sessionStorage['webchatToken'] = jsonResult.token;
sessionStorage['webchatUserId'] = jsonResult.userId;
console.log(`Got token from cloud`);
// refresh the token every 15 minutes.
setTimeout(() => {
refreshToken();
}, 60000 * 15); // 15 minutes
}
// If the request was not succesfull, retry.
else {
console.log(`Tried to get token, but goterror ` + res.status + `. Retrying.`);
await requestToken();
}
}
// If there is already a token in storage, refresh the existing one instead of requesting a new one.
else {
console.log(`Got token from sessionStorage`);
await refreshToken();
}
}
// Refreshes an existing token so it doesn't expire.
async function refreshToken() {
// Refresh the token if it exists in storage.
if (sessionStorage['webchatToken']) {
const res = await fetch('https://' + serviceName + '.azurewebsites.net/api/token/refresh?token=' + sessionStorage['webchatToken'],
{
method: 'POST'
});
// If refresh was succesfull we are done.
if (res.status == 200) {
console.log(`Refreshed token`);
}
// If refresh was not succesfull, clear the token from storage and request a new one. The token is probably expired.
else {
console.log(`Tried to refresh token, but got error ` + res.status + `. Requesting new token.`);
sessionStorage.clear();
await requestToken();
}
}
// If there is no token in storage, request a new token.
else {
console.log(`Tried to refresh token, but token is not defined. Requesting new token.`);
sessionStorage.clear();
await requestToken();
}
}
后端代碼：
[HttpGet]
[Route("api/token")]
public async Task<ObjectResult> GetToken()
{
HttpClient client = new HttpClient();
HttpRequestMessage request = new HttpRequestMessage(
HttpMethod.Post,
$"https://directline.botframework.com/v3/directline/tokens/generate");
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", _configuration.DirectLineKey);
var userId = $"dl_{Guid.NewGuid()}";
request.Content = new StringContent(
JsonConvert.SerializeObject(new { User = new { Id = userId } }),
Encoding.UTF8,
"application/json");
var response = await client.SendAsync(request);
string token = String.Empty;
int expiresIn = 0;
if (response.IsSuccessStatusCode)
{
var body = await response.Content.ReadAsStringAsync();
token = JsonConvert.DeserializeObject<DirectLineToken>(body).token;
expiresIn = JsonConvert.DeserializeObject<DirectLineToken>(body).expires_in;
}
return Ok(new { token, userId, expiresIn });
}
[HttpPost]
[Route("api/token/refresh/")]
public async Task<ObjectResult> RefreshToken(string token)
{
HttpClient client = new HttpClient();
HttpRequestMessage request = new HttpRequestMessage(
HttpMethod.Post,
$"https://directline.botframework.com/v3/directline/tokens/refresh");
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
var response = await client.SendAsync(request);
token = String.Empty;
int expiresIn = 0;
if (response.IsSuccessStatusCode)
{
var body = await response.Content.ReadAsStringAsync();
token = JsonConvert.DeserializeObject<DirectLineToken>(body).token;
expiresIn = JsonConvert.DeserializeObject<DirectLineToken>(body).expires_in;
}
if (string.IsNullOrEmpty(token))
return Problem("Token incorrect");
return Ok(new { token, expiresIn });
}
我希望發布這個可能對某人有用。
