Base64 improvements (#1635)

lib/inc/drogon/HttpClient.h

@@ -151,7 +151,7 @@ class DROGON_EXPORT HttpClient : public trantor::NonCopyable
      *
      * @param req
      * @param timeout In seconds. If the response is not received within the
-     * timeout, A `std::runtime_error` with the message "Timeout" is thrown.
+     * timeout, A `drogon::HttpException` with `ReqResult::Timeout` is thrown.
      * The zero value by default disables the timeout.
      *
      * @return internal::HttpRespAwaiter. Await on it to get the response
@@ -346,6 +346,29 @@ class DROGON_EXPORT HttpClient : public trantor::NonCopyable
 };
 
 #ifdef __cpp_impl_coroutine
+
+class HttpException : public std::exception
+{
+  public:
+    HttpException() = delete;
+    explicit HttpException(ReqResult res)
+        : resultCode_(res), message_(to_string_view(res))
+    {
+    }
+    const char *what() const noexcept override
+    {
+        return message_.data();
+    }
+    ReqResult code() const
+    {
+        return resultCode_;
+    }
+
+  private:
+    ReqResult resultCode_;
+    std::string_view message_;
+};
+
 inline void internal::HttpRespAwaiter::await_suspend(
     std::coroutine_handle<> handle)
 {
@@ -353,17 +376,11 @@ inline void internal::HttpRespAwaiter::await_suspend(
     assert(req_ != nullptr);
     client_->sendRequest(
         req_,
-        [handle = std::move(handle), this](ReqResult result,
-                                           const HttpResponsePtr &resp) {
+        [handle, this](ReqResult result, const HttpResponsePtr &resp) {
             if (result == ReqResult::Ok)
                 setValue(resp);
             else
-            {
-                std::stringstream ss;
-                ss << result;
-                setException(
-                    std::make_exception_ptr(std::runtime_error(ss.str())));
-            }
+                setException(std::make_exception_ptr(HttpException(result)));
             handle.resume();
         },
         timeout_);

lib/inc/drogon/HttpResponse.h

@@ -353,6 +353,9 @@ class DROGON_EXPORT HttpResponse
     /// Create a normal response with a status code of 200ok and a content type
     /// of text/html.
     static HttpResponsePtr newHttpResponse();
+    /// Create a response with a status code and a content type
+    static HttpResponsePtr newHttpResponse(HttpStatusCode code,
+                                           ContentType type);
     /// Create a response which returns a 404 page.
     static HttpResponsePtr newNotFoundResponse();
     /// Create a response which returns a json object. Its content type is set

lib/inc/drogon/utils/Utilities.h

@@ -60,6 +60,9 @@ namespace utils
 /// Determine if the string is an integer
 DROGON_EXPORT bool isInteger(const std::string &str);
 
+/// Determine if the string is base64 encoded
+DROGON_EXPORT bool isBase64(const std::string &str);
+
 /// Generate random a string
 /**
  * @param length The string length
@@ -98,15 +101,46 @@ DROGON_EXPORT std::set<std::string> splitStringToSet(
 /// Get UUID string.
 DROGON_EXPORT std::string getUuid();
 
+/// Get the encoded length of base64.
+DROGON_EXPORT size_t base64EncodedLength(unsigned int in_len,
+                                         bool padded = true);
+
 /// Encode the string to base64 format.
 DROGON_EXPORT std::string base64Encode(const unsigned char *bytes_to_encode,
                                        unsigned int in_len,
-                                       bool url_safe = false);
+                                       bool url_safe = false,
+                                       bool padded = true);
+
+/// Encode the string to base64 format.
+inline std::string base64Encode(string_view data,
+                                bool url_safe = false,
+                                bool padded = true)
+{
+    return base64Encode((unsigned char *)data.data(),
+                        data.size(),
+                        url_safe,
+                        padded);
+}
+
+/// Encode the string to base64 format with no padding.
+DROGON_EXPORT std::string base64EncodeUnpadded(
+    const unsigned char *bytes_to_encode,
+    unsigned int in_len,
+    bool url_safe = false);
+
+/// Encode the string to base64 format with no padding.
+inline std::string base64EncodeUnpadded(string_view data, bool url_safe = false)
+{
+    return base64Encode(data, url_safe, false);
+}
+
+/// Get the decoded length of base64.
+DROGON_EXPORT size_t base64DecodedLength(unsigned int in_len);
 
 /// Decode the base64 format string.
-DROGON_EXPORT std::string base64Decode(const std::string &encoded_string);
+DROGON_EXPORT std::string base64Decode(string_view encoded_string);
 DROGON_EXPORT std::vector<char> base64DecodeToVector(
-    const std::string &encoded_string);
+    string_view encoded_string);
 
 /// Check if the string need decoding
 DROGON_EXPORT bool needUrlDecoding(const char *begin, const char *end);

lib/src/HttpResponseImpl.cc

@@ -71,6 +71,14 @@ HttpResponsePtr HttpResponse::newHttpResponse()
     return res;
 }
 
+HttpResponsePtr HttpResponse::newHttpResponse(HttpStatusCode code,
+                                              ContentType type)
+{
+    auto res = std::make_shared<HttpResponseImpl>(code, type);
+    doResponseCreateAdvices(res);
+    return res;
+}
+
 HttpResponsePtr HttpResponse::newHttpJsonResponse(const Json::Value &data)
 {
     auto res = std::make_shared<HttpResponseImpl>(k200OK, CT_APPLICATION_JSON);

lib/src/Utilities.cc

@@ -149,6 +149,14 @@ bool isInteger(const std::string &str)
     return true;
 }
 
+bool isBase64(const std::string &str)
+{
+    for (auto c : str)
+        if (!isBase64(c))
+            return false;
+    return true;
+}
+
 std::string genRandomString(int length)
 {
     static const char char_space[] =
@@ -387,11 +395,18 @@ std::string getUuid()
 #endif
 }
 
+size_t base64EncodedLength(unsigned int in_len, bool padded)
+{
+    return padded ? ((in_len + 3 - 1) / 3) * 4 : (in_len * 8 + 6 - 1) / 6;
+}
+
 std::string base64Encode(const unsigned char *bytes_to_encode,
                          unsigned int in_len,
-                         bool url_safe)
+                         bool url_safe,
+                         bool padded)
 {
     std::string ret;
+    ret.reserve(base64EncodedLength(in_len, padded));
     int i = 0;
     unsigned char char_array_3[3];
     unsigned char char_array_4[4];
@@ -428,27 +443,45 @@ std::string base64Encode(const unsigned char *bytes_to_encode,
             ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
         char_array_4[3] = char_array_3[2] & 0x3f;
 
-        for (int j = 0; (j < i + 1); ++j)
+        for (int j = 0; (j <= i); ++j)
             ret += charSet[char_array_4[j]];
 
-        while ((i++ < 3))
-            ret += '=';
+        if (padded)
+            while ((++i < 4))
+                ret += '=';
     }
     return ret;
 }
 
-std::vector<char> base64DecodeToVector(const std::string &encoded_string)
+std::string base64EncodeUnpadded(const unsigned char *bytes_to_encode,
+                                 unsigned int in_len,
+                                 bool url_safe)
+{
+    return base64Encode(bytes_to_encode, in_len, url_safe, false);
+}
+
+size_t base64DecodedLength(unsigned int in_len)
+{
+    return (in_len * 3) / 4;
+}
+
+std::vector<char> base64DecodeToVector(string_view encoded_string)
 {
     auto in_len = encoded_string.size();
     int i = 0;
     int in_{0};
     char char_array_4[4], char_array_3[3];
     std::vector<char> ret;
-    ret.reserve(in_len);
+    ret.reserve(base64DecodedLength(in_len));
 
-    while (in_len-- && (encoded_string[in_] != '=') &&
-           isBase64(encoded_string[in_]))
+    while (in_len-- && (encoded_string[in_] != '='))
     {
+        if (!isBase64(encoded_string[in_]))
+        {
+            ++in_;
+            continue;
+        }
+
         char_array_4[i++] = encoded_string[in_];
         ++in_;
         if (i == 4)
@@ -486,24 +519,31 @@ std::vector<char> base64DecodeToVector(const std::string &encoded_string)
             ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
         char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
 
-        for (int j = 0; (j < i - 1); ++j)
+        --i;
+        for (int j = 0; (j < i); ++j)
             ret.push_back(char_array_3[j]);
     }
 
     return ret;
 }
 
-std::string base64Decode(const std::string &encoded_string)
+std::string base64Decode(string_view encoded_string)
 {
     auto in_len = encoded_string.size();
     int i = 0;
     int in_{0};
     unsigned char char_array_4[4], char_array_3[3];
     std::string ret;
+    ret.reserve(base64DecodedLength(in_len));
 
-    while (in_len-- && (encoded_string[in_] != '=') &&
-           isBase64(encoded_string[in_]))
+    while (in_len-- && (encoded_string[in_] != '='))
     {
+        if (!isBase64(encoded_string[in_]))
+        {
+            ++in_;
+            continue;
+        }
+
         char_array_4[i++] = encoded_string[in_];
         ++in_;
         if (i == 4)
@@ -540,7 +580,8 @@ std::string base64Decode(const std::string &encoded_string)
             ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
         char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
 
-        for (int j = 0; (j < i - 1); ++j)
+        --i;
+        for (int j = 0; (j < i); ++j)
             ret += char_array_3[j];
     }
 

lib/tests/unittests/Base64Test.cc

@@ -5,12 +5,34 @@
 DROGON_TEST(Base64)
 {
     std::string in{"drogon framework"};
-    auto encoded = drogon::utils::base64Encode((const unsigned char *)in.data(),
-                                               (unsigned int)in.length());
+    auto encoded = drogon::utils::base64Encode(in);
     auto decoded = drogon::utils::base64Decode(encoded);
     CHECK(encoded == "ZHJvZ29uIGZyYW1ld29yaw==");
     CHECK(decoded == in);
 
+    SUBSECTION(InvalidChars)
+    {
+        auto decoded =
+            drogon::utils::base64Decode("ZHJvZ2*9uIGZy**YW1ld2***9yaw*=*=");
+        CHECK(decoded == in);
+    }
+
+    SUBSECTION(InvalidCharsNoPadding)
+    {
+        auto decoded =
+            drogon::utils::base64Decode("ZHJvZ2*9uIGZy**YW1ld2***9yaw**");
+        CHECK(decoded == in);
+    }
+
+    SUBSECTION(Unpadded)
+    {
+        std::string in{"drogon framework"};
+        auto encoded = drogon::utils::base64EncodeUnpadded(in);
+        auto decoded = drogon::utils::base64Decode(encoded);
+        CHECK(encoded == "ZHJvZ29uIGZyYW1ld29yaw");
+        CHECK(decoded == in);
+    }
+
     SUBSECTION(LongString)
     {
         std::string in;
@@ -19,12 +41,9 @@ DROGON_TEST(Base64)
         {
             in.append(1, char(i));
         }
-        auto out = drogon::utils::base64Encode((const unsigned char *)in.data(),
-                                               (unsigned int)in.length());
+        auto out = drogon::utils::base64Encode(in);
         auto out2 = drogon::utils::base64Decode(out);
-        auto encoded =
-            drogon::utils::base64Encode((const unsigned char *)in.data(),
-                                        (unsigned int)in.length());
+        auto encoded = drogon::utils::base64Encode(in);
         auto decoded = drogon::utils::base64Decode(encoded);
         CHECK(decoded == in);
     }
@@ -32,15 +51,21 @@ DROGON_TEST(Base64)
     SUBSECTION(URLSafe)
     {
         std::string in{"drogon framework"};
-        auto encoded =
-            drogon::utils::base64Encode((const unsigned char *)in.data(),
-                                        (unsigned int)in.length(),
-                                        true);
+        auto encoded = drogon::utils::base64Encode(in, true);
         auto decoded = drogon::utils::base64Decode(encoded);
         CHECK(encoded == "ZHJvZ29uIGZyYW1ld29yaw==");
         CHECK(decoded == in);
     }
 
+    SUBSECTION(UnpaddedURLSafe)
+    {
+        std::string in{"drogon framework"};
+        auto encoded = drogon::utils::base64EncodeUnpadded(in, true);
+        auto decoded = drogon::utils::base64Decode(encoded);
+        CHECK(encoded == "ZHJvZ29uIGZyYW1ld29yaw");
+        CHECK(decoded == in);
+    }
+
     SUBSECTION(LongURLSafe)
     {
         std::string in;
@@ -49,10 +74,7 @@ DROGON_TEST(Base64)
         {
             in.append(1, char(i));
         }
-        auto encoded =
-            drogon::utils::base64Encode((const unsigned char *)in.data(),
-                                        (unsigned int)in.length(),
-                                        true);
+        auto encoded = drogon::utils::base64Encode(in, true);
         auto decoded = drogon::utils::base64Decode(encoded);
         CHECK(decoded == in);
     }