Add API Key parsing for experimental APIs

content/browser/experiments/api_key.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_EXPERIMENTS_API_KEY_H_
+#define CONTENT_BROWSER_EXPERIMENTS_API_KEY_H_
+
+#include <string>
+
+#include "base/time/time.h"
+#include "content/common/content_export.h"
+#include "url/gurl.h"
+
+namespace content {
+
+class ApiKeyTest;

[chasej, 2015/12/15 19:43:41]

It doesn't look like this is needed. I'm guessing it's left over from a friend
declaration, since removed?

[iclelland, 2015/12/15 21:22:24]

Yep. Done.

+
+// The Experimental Framework (EF) provides limited access to experimental APIs,
+// on a per-origin basis.  This class defines the API key data structure, used
+// to securely provide access to an experimental API.
+//
+// Experimental APIs are defined by string names, provided by the implementers.
+// The EF code does not maintain an enum or constant list for experiment names.
+// Instead, the EF validates the name provided by the API implementation against
+// any provided API keys.
+// TODO(chasej): Link to documentation, or provide more detail on keys, .etc
+class CONTENT_EXPORT ApiKey {
+ public:
+  ~ApiKey();
+
+  // Returns a key object if the string represents a well-formed key, or
+  // nullptr otherwise.
+  static scoped_ptr<ApiKey> Parse(const std::string&);
+
+  // Returns true if this API key has a valid signature, and has not expired.
+  bool IsValidNow(const base::Time& now) const;
+
+  std::string signature() { return signature_; }
+  std::string data() { return data_; }
+  GURL origin() { return origin_; }
+  std::string api_name() { return api_name_; }
+  uint64_t expiry() { return expiry_; }

[chasej, 2015/12/15 19:43:41]

Should this have a comment to indicate the date format (i.e. UTC timestamp)?

[iclelland, 2015/12/15 21:22:24]

Done. Added explanatory comments to all member variables. Also renamed this to
expiry_timestamp_ to be extra clear.

+
+ private:
+  ApiKey();
+  ApiKey(const std::string& signature,
+         const std::string& data,
+         const GURL& origin,
+         const std::string& api_name,
+         uint64_t expiry);
+
+  std::string signature_;
+  std::string data_;
+  GURL origin_;
+  std::string api_name_;
+  uint64_t expiry_;
+};
+
+}  // namespace
+#endif  // CONTENT_BROWSER_EXPERIMENTS_API_KEY_H_