Implement RsGxsForums link import/export

libretroshare/src/retroshare/rsgxsforums.h

@@ -241,6 +241,62 @@ public:
 	virtual bool subscribeToForum( const RsGxsGroupId& forumId,
 	                               bool subscribe ) = 0;
 
+	/// default base URL used for forums links @see exportForumLink
+	static const std::string DEFAULT_FORUM_BASE_URL;
+
+	/// Link query field used to store forum name @see exportForumLink
+	static const std::string FORUM_URL_NAME_FIELD;
+
+	/// Link query field used to store forum id @see exportForumLink
+	static const std::string FORUM_URL_ID_FIELD;
+
+	/// Link query field used to store forum data @see exportForumLink
+	static const std::string FORUM_URL_DATA_FIELD;
+
+	/** Link query field used to store forum message title
+	 * @see exportChannelLink */
+	static const std::string FORUM_URL_MSG_TITLE_FIELD;
+
+	/// Link query field used to store forum message id @see exportChannelLink
+	static const std::string FORUM_URL_MSG_ID_FIELD;
+
+	/**
+	 * @brief Get link to a forum
+	 * @jsonapi{development}
+	 * @param[out] link storage for the generated link
+	 * @param[in] forumId Id of the forum of which we want to generate a link
+	 * @param[in] includeGxsData if true include the forum GXS group data so
+	 *	the receiver can subscribe to the forum even if she hasn't received it
+	 *	through GXS yet
+	 * @param[in] baseUrl URL into which to sneak in the RetroShare link
+	 *	radix, this is primarly useful to induce applications into making the
+	 *	link clickable, or to disguise the RetroShare link into a
+	 *	"normal" looking web link. If empty the GXS data link will be outputted
+	 *	in plain base64 format.
+	 * @param[out] errMsg optional storage for error message, meaningful only in
+	 *	case of failure
+	 * @return false if something failed, true otherwhise
+	 */
+	virtual bool exportForumLink(
+	        std::string& link, const RsGxsGroupId& forumId,
+	        bool includeGxsData = true,
+	        const std::string& baseUrl = RsGxsForums::DEFAULT_FORUM_BASE_URL,
+	        std::string& errMsg = RS_DEFAULT_STORAGE_PARAM(std::string) ) = 0;
+
+	/**
+	 * @brief Import forum from full link
+	 * @param[in] link forum link either in radix or URL format
+	 * @param[out] forumId optional storage for parsed forum id
+	 * @param[out] errMsg optional storage for error message, meaningful only in
+	 *	case of failure
+	 * @return false if some error occurred, true otherwise
+	 */
+	virtual bool importForumLink(
+	        const std::string& link,
+	        RsGxsGroupId& forumId = RS_DEFAULT_STORAGE_PARAM(RsGxsGroupId),
+	        std::string& errMsg = RS_DEFAULT_STORAGE_PARAM(std::string) ) = 0;
+
+
 	/**
 	 * @brief Create forum. Blocking API.
 	 * @jsonapi{development}

libretroshare/src/services/p3gxsforums.cc

@@ -676,6 +676,72 @@ bool p3GxsForums::subscribeToForum(
 	return true;
 }
 
+bool p3GxsForums::exportForumLink(
+        std::string& link, const RsGxsGroupId& forumId, bool includeGxsData,
+        const std::string& baseUrl, std::string& errMsg )
+{
+	constexpr auto fname = __PRETTY_FUNCTION__;
+	const auto failure = [&](const std::string& err)
+	{
+		errMsg = err;
+		RsErr() << fname << " " << err << std::endl;
+		return false;
+	};
+
+	if(forumId.isNull()) return failure("forumId cannot be null");
+
+	const bool outputRadix = baseUrl.empty();
+	if(outputRadix && !includeGxsData) return
+	        failure("includeGxsData must be true if format requested is base64");
+
+	if( includeGxsData &&
+	        !RsGenExchange::exportGroupBase64(link, forumId, errMsg) )
+		return failure(errMsg);
+
+	if(outputRadix) return true;
+
+	std::vector<RsGxsForumGroup> forumsInfo;
+	if( !getForumsInfo(std::list<RsGxsGroupId>({forumId}), forumsInfo)
+	        || forumsInfo.empty() )
+		return failure("failure retrieving forum information");
+
+	RsUrl inviteUrl(baseUrl);
+	inviteUrl.setQueryKV(FORUM_URL_ID_FIELD, forumId.toStdString());
+	inviteUrl.setQueryKV(FORUM_URL_NAME_FIELD, forumsInfo[0].mMeta.mGroupName);
+	if(includeGxsData) inviteUrl.setQueryKV(FORUM_URL_DATA_FIELD, link);
+
+	link = inviteUrl.toString();
+	return true;
+}
+
+bool p3GxsForums::importForumLink(
+        const std::string& link, RsGxsGroupId& forumId, std::string& errMsg )
+{
+	constexpr auto fname = __PRETTY_FUNCTION__;
+	const auto failure = [&](const std::string& err)
+	{
+		errMsg = err;
+		RsErr() << fname << " " << err << std::endl;
+		return false;
+	};
+
+	if(link.empty()) return failure("link is empty");
+
+	const std::string* radixPtr(&link);
+
+	RsUrl url(link);
+	const auto& query = url.query();
+	const auto qIt = query.find(FORUM_URL_DATA_FIELD);
+	if(qIt != query.end()) radixPtr = &qIt->second;
+
+	if(radixPtr->empty()) return failure(FORUM_URL_DATA_FIELD + " is empty");
+
+	if(!RsGenExchange::importGroupBase64(*radixPtr, forumId, errMsg))
+		return failure(errMsg);
+
+	return true;
+}
+
 bool p3GxsForums::createGroup(uint32_t &token, RsGxsForumGroup &group)
 {
 	std::cerr << "p3GxsForums::createGroup()" << std::endl;
@@ -1005,6 +1071,19 @@ bool RsGxsForumGroup::canEditPosts(const RsGxsId& id) const
 	        id == mMeta.mAuthorId;
 }
 
+/*static*/ const std::string RsGxsForums::DEFAULT_FORUM_BASE_URL =
+        "retroshare:///forums";
+/*static*/ const std::string RsGxsForums::FORUM_URL_NAME_FIELD =
+        "forumName";
+/*static*/ const std::string RsGxsForums::FORUM_URL_ID_FIELD =
+        "forumId";
+/*static*/ const std::string RsGxsForums::FORUM_URL_DATA_FIELD =
+        "forumData";
+/*static*/ const std::string RsGxsForums::FORUM_URL_MSG_TITLE_FIELD =
+        "forumMsgTitle";
+/*static*/ const std::string RsGxsForums::FORUM_URL_MSG_ID_FIELD =
+        "forumMsgId";
+
 RsGxsForumGroup::~RsGxsForumGroup() = default;
 RsGxsForumMsg::~RsGxsForumMsg() = default;
 RsGxsForums::~RsGxsForums() = default;

libretroshare/src/services/p3gxsforums.h

@@ -110,6 +110,21 @@ public:
 	virtual bool subscribeToForum( const RsGxsGroupId& forumId,
 	                               bool subscribe );
 
+	/// @see RsGxsForums
+	bool exportForumLink(
+	        std::string& link, const RsGxsGroupId& forumId,
+	        bool includeGxsData = true,
+	        const std::string& baseUrl = DEFAULT_FORUM_BASE_URL,
+	        std::string& errMsg = RS_DEFAULT_STORAGE_PARAM(std::string)
+	        ) override;
+
+	/// @see RsGxsForums
+	bool importForumLink(
+	        const std::string& link,
+	        RsGxsGroupId& forumId = RS_DEFAULT_STORAGE_PARAM(RsGxsGroupId),
+	        std::string& errMsg = RS_DEFAULT_STORAGE_PARAM(std::string)
+	        ) override;
+
 	virtual bool getGroupData(const uint32_t &token, std::vector<RsGxsForumGroup> &groups);
 	virtual bool getMsgData(const uint32_t &token, std::vector<RsGxsForumMsg> &msgs);
 	virtual bool getMsgMetaData(const uint32_t &token, GxsMsgMetaMap& msg_metas);