更新

vendor/alibabacloud/credentials/src/Providers/SessionCredentialsProvider.php

@@ -0,0 +1,161 @@
+<?php
+
+namespace AlibabaCloud\Credentials\Providers;
+
+use AlibabaCloud\Credentials\Credential\RefreshResult;
+
+abstract class SessionCredentialsProvider implements CredentialsProvider
+{
+    /**
+     * @var array
+     */
+    protected static $credentialsCache = [];
+
+    /**
+     * Expiration time slot for temporary security credentials.
+     *
+     * @var int
+     */
+    protected $expirationSlot = 180;
+
+    /**
+     * @var string
+     */
+    protected $error = 'Result contains no credentials';
+
+    /**
+     * Get the credentials from the cache in the validity period.
+     *
+     * @return RefreshResult|null
+     */
+    protected function getCredentialsInCache()
+    {
+        if (isset(self::$credentialsCache[$this->key()])) {
+            $result = self::$credentialsCache[$this->key()];
+            return $result;
+        }
+        return null;
+    }
+
+    /**
+     * Cache credentials.
+     *
+     * @param RefreshResult $credential
+     */
+    protected function cache(RefreshResult $credential)
+    {
+        self::$credentialsCache[$this->key()] = $credential;
+    }
+
+    /**
+     * Get credential.
+     *
+     * @return Credentials
+     */
+    public function getCredentials()
+    {
+        if ($this->cacheIsStale() || $this->shouldInitiateCachePrefetch()) {
+            $result = $this->refreshCache();
+            $this->cache($result);
+        }
+
+        $result = $this->getCredentialsInCache();
+
+        return $result->credentials();
+    }
+
+    /**
+     * @return RefreshResult
+     */
+    protected function refreshCache()
+    {
+        try {
+            return $this->handleFetchedSuccess($this->refreshCredentials());
+        } catch (\Exception $e) {
+            return $this->handleFetchedFailure($e);
+        }
+    }
+
+    /**
+     * @return RefreshResult
+     * @throws \Exception
+     */
+    protected function handleFetchedFailure(\Exception $e)
+    {
+        $currentCachedValue = $this->getCredentialsInCache();
+        if (is_null($currentCachedValue)) {
+            throw $e;
+        }
+
+        if (time() < $currentCachedValue->staleTime()) {
+            return $currentCachedValue;
+        }
+
+        throw $e;
+    }
+    /**
+     * @return RefreshResult
+     */
+    protected function handleFetchedSuccess(RefreshResult $value)
+    {
+        $now = time();
+        // 过期时间大于15分钟，不用管
+        if ($now < $value->staleTime()) {
+            return $value;
+        }
+        // 不足或等于15分钟，但未过期，下次会再次刷新
+        if ($now < $value->staleTime() + 15 * 60) {
+            $value->staleTime = $now;
+            return $value;
+        }
+        // 已过期，看缓存，缓存若大于15分钟，返回缓存，若小于15分钟，则稍后重试
+        if (is_null($this->getCredentialsInCache())) {
+            throw new \Exception("The fetched credentials have expired and no cache is available.");
+        } else if ($now < $this->getCredentialsInCache()->staleTime()) {
+            return $this->getCredentialsInCache();
+        } else {
+            // 返回成功，延长有效期 1 分钟
+            $expectation = mt_rand(50, 70);
+            $value->staleTime = time() + $expectation;
+            return $value;
+        }
+    }
+
+    /**
+     * @return bool
+     */
+    protected function cacheIsStale()
+    {
+        return is_null($this->getCredentialsInCache()) || time() >= $this->getCredentialsInCache()->staleTime();
+    }
+
+    /**
+     * @return bool
+     */
+    protected function shouldInitiateCachePrefetch()
+    {
+        return is_null($this->getCredentialsInCache()) || time() >= $this->getCredentialsInCache()->prefetchTime();
+    }
+
+    /**
+     * @return int
+     */
+    public function getStaleTime($expiration)
+    {
+        return $expiration <= 0 ?
+            time() + (60 * 60) :
+            $expiration - (15 * 60);
+    }
+
+    /**
+     * @return RefreshResult
+     */
+    abstract function refreshCredentials();
+
+    /**
+     * Get the toString of the credentials provider as the key.
+     *
+     * @return string
+     */
+    abstract function key();
+}