Add method to download data through matrix content URIs

include/mtxclient/http/client.hpp

@@ -172,6 +172,11 @@ public:
                     const std::string &filename,
                     Callback<mtx::responses::ContentURI> cb);
         //! Retrieve data from the content repository.
+        void download(const std::string &mxc_url,
+                      std::function<void(const std::string &data,
+                                         const std::string &content_type,
+                                         const std::string &original_filename,
+                                         RequestErr err)> cb);
         void download(const std::string &server,
                       const std::string &media_id,
                       std::function<void(const std::string &data,

include/mtxclient/utils.hpp

@@ -10,6 +10,19 @@ namespace mtx {
 namespace client {
 namespace utils {
 
+//! Representation of Matrix Content (MXC) URIs.
+struct MxcUrl
+{
+        //! The name of the homeserver where the content originated.
+        std::string server;
+        //! An opaque ID which identifies the content.
+        std::string media_id;
+};
+
+//! Parse a matrix content URI into its server & media_id components.
+MxcUrl
+parse_mxc_url(const std::string &url);
+
 //! Check if the given string represents a number.
 bool
 is_number(const std::string &s);

lib/http/client.cpp

@@ -231,6 +231,17 @@ Client::upload(const std::string &data,
         post<std::string, mtx::responses::ContentURI>(api_path, data, cb, true, content_type);
 }
 
+void
+Client::download(const std::string &mxc_url,
+                 std::function<void(const std::string &res,
+                                    const std::string &content_type,
+                                    const std::string &original_filename,
+                                    RequestErr err)> callback)
+{
+        auto url = mtx::client::utils::parse_mxc_url(mxc_url);
+        download(url.server, url.media_id, std::move(callback));
+}
+
 void
 Client::download(const std::string &server,
                  const std::string &media_id,

lib/utils.cpp

@@ -4,6 +4,7 @@
 #include <string>
 #include <utility>
 
+#include <boost/algorithm/string.hpp>
 #include <boost/iostreams/copy.hpp>
 #include <boost/iostreams/detail/error.hpp>
 #include <boost/iostreams/detail/forward.hpp>
@@ -14,6 +15,31 @@
 #include <boost/random/random_device.hpp>
 #include <boost/random/uniform_int_distribution.hpp>
 
+mtx::client::utils::MxcUrl
+mtx::client::utils::parse_mxc_url(const std::string &url)
+{
+        constexpr auto mxc_uri_protocol = "mxc://";
+        MxcUrl res;
+
+        if (url.find(mxc_uri_protocol) != 0)
+                return res;
+
+        auto str_left = url.substr(6);
+
+        std::vector<std::string> parts;
+        boost::split(parts, str_left, [](char c) { return c == '/'; });
+
+        if (parts.size() != 2) {
+                res.server = parts.at(0);
+                return res;
+        }
+
+        res.server   = parts.at(0);
+        res.media_id = parts.at(1);
+
+        return res;
+}
+
 bool
 mtx::client::utils::is_number(const std::string &s)
 {

tests/media_api.cpp

@@ -16,15 +16,6 @@ using namespace mtx::identifiers;
 
 using namespace std;
 
-string
-get_media_id(const mtx::responses::ContentURI &res)
-{
-        vector<string> results;
-        boost::split(results, res.content_uri, [](char c) { return c == '/'; });
-
-        return results.back();
-}
-
 string
 read_file(const string &file_path)
 {
@@ -56,8 +47,7 @@ TEST(MediaAPI, UploadTextFile)
                               [alice, text](const mtx::responses::ContentURI &res, RequestErr err) {
                                       validate_upload(res, err);
 
-                                      alice->download("localhost",
-                                                      get_media_id(res),
+                                      alice->download(res.content_uri,
                                                       [text](const string &data,
                                                              const string &content_type,
                                                              const string &original_filename,
@@ -89,8 +79,7 @@ TEST(MediaAPI, UploadAudio)
                             [bob, audio](const mtx::responses::ContentURI &res, RequestErr err) {
                                     validate_upload(res, err);
 
-                                    bob->download("localhost",
-                                                  get_media_id(res),
+                                    bob->download(res.content_uri,
                                                   [audio](const string &data,
                                                           const string &content_type,
                                                           const string &original_filename,
@@ -121,8 +110,7 @@ TEST(MediaAPI, UploadImage)
                              [carl, img](const mtx::responses::ContentURI &res, RequestErr err) {
                                      validate_upload(res, err);
 
-                                     carl->download("localhost",
-                                                    get_media_id(res),
+                                     carl->download(res.content_uri,
                                                     [img](const string &data,
                                                           const string &content_type,
                                                           const string &original_filename,