Merge pull request #218 from kiwix/downloadPauseResume

Add pause and unpause functions for aria2

include/downloader.h

@@ -54,6 +54,9 @@ class Download {
       m_status(K_UNKNOWN),
       m_did(did) {};
   void updateStatus(bool follow=false);
+  void pauseDownload();
+  void resumeDownload();
+  void cancelDownload();
   StatusResult getStatus()          { return m_status; }
   std::string  getDid()             { return m_did; }
   std::string  getFollowedBy()      { return m_followedBy; }

src/aria2.cpp

@@ -171,7 +171,6 @@ std::vector<std::string> Aria2::tellActive()
   MethodCall methodCall("aria2.tellActive", m_secret);
   auto statusArray = methodCall.newParamValue().getArray();
   statusArray.addValue().set(std::string("gid"));
-  statusArray.addValue().set(std::string("following"));
   auto responseContent = doRequest(methodCall);
   MethodResponse response(responseContent);
   std::vector<std::string> activeGID;
@@ -186,6 +185,27 @@ std::vector<std::string> Aria2::tellActive()
   return activeGID;
 }
 
+std::vector<std::string> Aria2::tellWaiting()
+{
+  MethodCall methodCall("aria2.tellWaiting", m_secret);
+  methodCall.newParamValue().set(0);
+  methodCall.newParamValue().set(99); // max number of downloads to be returned, don't know how to set this properly assumed that there will not be more than 99 paused downloads.
+  auto statusArray = methodCall.newParamValue().getArray();
+  statusArray.addValue().set(std::string("gid"));
+  auto responseContent = doRequest(methodCall);
+  MethodResponse response(responseContent);
+  std::vector<std::string> waitingGID;
+  int index = 0;
+  while(true) {
+    try {
+      auto structNode = response.getParamValue(0).getArray().getValue(index++).getStruct();
+      auto gidNode = structNode.getMember("gid");
+      waitingGID.push_back(gidNode.getValue().getAsS());
+    } catch (InvalidRPCNode& e) { break; }
+  }
+  return waitingGID;
+}
+
 void Aria2::saveSession()
 {
   MethodCall methodCall("aria2.saveSession", m_secret);
@@ -199,5 +219,25 @@ void Aria2::shutdown()
   doRequest(methodCall);
 }
 
+void Aria2::pause(const std::string& gid)
+{
+    MethodCall methodCall("aria2.pause", m_secret);
+    methodCall.newParamValue().set(gid);
+    doRequest(methodCall);
+}
+
+void Aria2::unpause(const std::string& gid)
+{
+    MethodCall methodCall("aria2.unpause", m_secret);
+    methodCall.newParamValue().set(gid);
+    doRequest(methodCall);
+}
+
+void Aria2::remove(const std::string& gid)
+{
+    MethodCall methodCall("aria2.remove", m_secret);
+    methodCall.newParamValue().set(gid);
+    doRequest(methodCall);
+}
 
 } // end namespace kiwix

src/aria2.h

@@ -37,8 +37,12 @@ class Aria2
     std::string addUri(const std::vector<std::string>& uri);
     std::string tellStatus(const std::string& gid, const std::vector<std::string>& statusKey);
     std::vector<std::string> tellActive();
+    std::vector<std::string> tellWaiting();
     void saveSession();
     void shutdown();
+    void pause(const std::string& gid);
+    void unpause(const std::string& gid);
+    void remove(const std::string& gid);
 };
 
 }; //end namespace kiwix

src/downloader.cpp

@@ -36,6 +36,8 @@ namespace kiwix
 
 void Download::updateStatus(bool follow)
 {
+  if (m_status == Download::K_REMOVED)
+    return;
   static std::vector<std::string> statusKey = {"status", "files", "totalLength",
                                                "completedLength", "followedBy",
                                                "downloadSpeed", "verifiedLength"};
@@ -93,6 +95,33 @@ void Download::updateStatus(bool follow)
   }
 }
 
+void Download::resumeDownload()
+{
+    if (!m_followedBy.empty())
+        mp_aria->unpause(m_followedBy);
+    else
+        mp_aria->unpause(m_did);
+    updateStatus(true);
+}
+
+void Download::pauseDownload()
+{
+    if (!m_followedBy.empty())
+        mp_aria->pause(m_followedBy);
+    else
+        mp_aria->pause(m_did);
+    updateStatus(true);
+}
+
+void Download::cancelDownload()
+{
+    if (!m_followedBy.empty())
+        mp_aria->remove(m_followedBy);
+    else
+        mp_aria->remove(m_did);
+    m_status = Download::K_REMOVED;
+}
+
 /* Constructor */
 Downloader::Downloader() :
   mp_aria(new Aria2())
@@ -101,6 +130,10 @@ Downloader::Downloader() :
     m_knownDownloads[gid] = std::unique_ptr<Download>(new Download(mp_aria, gid));
     m_knownDownloads[gid]->updateStatus();
   }
+  for (auto gid : mp_aria->tellWaiting()) {
+    m_knownDownloads[gid] = std::unique_ptr<Download>(new Download(mp_aria, gid));
+    m_knownDownloads[gid]->updateStatus();
+  }
 }
 
 
@@ -139,14 +172,23 @@ Download* Downloader::startDownload(const std::string& uri)
 Download* Downloader::getDownload(const std::string& did)
 {
   try {
+    m_knownDownloads.at(did).get()->updateStatus(true);
     return m_knownDownloads.at(did).get();
   } catch(exception& e) {
     for (auto gid : mp_aria->tellActive()) {
       if (gid == did) {
         m_knownDownloads[gid] = std::unique_ptr<Download>(new Download(mp_aria, gid));
+        m_knownDownloads.at(gid).get()->updateStatus(true);
         return m_knownDownloads[gid].get();
       }
     }
+    for (auto gid : mp_aria->tellWaiting()) {
+      if (gid == did) {
+        m_knownDownloads[gid] = std::unique_ptr<Download>(new Download(mp_aria, gid));
+        m_knownDownloads.at(gid).get()->updateStatus(true);
+        return m_knownDownloads[gid].get();
+      }
+  }
     throw e;
   }
 }