From ca829a3a98bbe3a69064d1bbb230358aee4e0f51 Mon Sep 17 00:00:00 2001
From: Benjamin Sergeant <bsergean@gmail.com>
Date: Fri, 10 Jul 2020 16:07:51 -0700
Subject: [PATCH] implement very very simple stream sql support

---
 ixsnake/ixsnake/IXSnakeProtocol.cpp | 16 +++++++++-
 ixsnake/ixsnake/IXStreamSql.cpp     | 48 +++++++++++++++++++++++++++--
 ixsnake/ixsnake/IXStreamSql.h       |  9 ++++--
 test/IXCobraToStdoutBotTest.cpp     |  3 ++
 test/IXStreamSqlTest.cpp            | 22 +++++++++----
 5 files changed, 86 insertions(+), 12 deletions(-)

diff --git a/ixsnake/ixsnake/IXSnakeProtocol.cpp b/ixsnake/ixsnake/IXSnakeProtocol.cpp
index 8b85c136..99310546 100644
--- a/ixsnake/ixsnake/IXSnakeProtocol.cpp
+++ b/ixsnake/ixsnake/IXSnakeProtocol.cpp
@@ -8,6 +8,7 @@
 
 #include "IXAppConfig.h"
 #include "IXSnakeConnectionState.h"
+#include "IXStreamSql.h"
 #include "nlohmann/json.hpp"
 #include <iostream>
 #include <ixcore/utils/IXCoreLogger.h>
@@ -187,12 +188,25 @@ namespace snake
             }
         }
 
+        std::string filterStr;
+        if (pdu["body"].find("filter") != pdu["body"].end())
+        {
+            std::string filterStr = pdu["body"]["filter"];
+        }
+
+        std::unique_ptr<StreamSql> streamSql = std::make_unique<StreamSql>(filterStr);
+
         int id = 0;
-        auto callback = [ws, &id, &subscriptionId](const std::string& messageStr) {
+        auto callback = [ws, &id, &subscriptionId, &streamSql](const std::string& messageStr) {
             auto msg = nlohmann::json::parse(messageStr);
 
             msg = msg["body"]["message"];
 
+            if (streamSql->valid() && !streamSql->match(msg))
+            {
+                return;
+            }
+
             nlohmann::json response = {
                 {"action", "rtm/subscription/data"},
                 {"id", id++},
diff --git a/ixsnake/ixsnake/IXStreamSql.cpp b/ixsnake/ixsnake/IXStreamSql.cpp
index 49d4d24c..6431b34c 100644
--- a/ixsnake/ixsnake/IXStreamSql.cpp
+++ b/ixsnake/ixsnake/IXStreamSql.cpp
@@ -2,20 +2,62 @@
  *  IXStreamSql.cpp
  *  Author: Benjamin Sergeant
  *  Copyright (c) 2020 Machine Zone, Inc. All rights reserved.
+ *
+ *  Super simple hacked up version of a stream sql expression,
+ *  that only supports non nested field evaluation
  */
 
 #include "IXStreamSql.h"
+#include <sstream>
+#include <iostream>
 
 namespace snake
 {
     StreamSql::StreamSql(const std::string& sqlFilter)
+        : _valid(false)
     {
-        ;
+        std::string token;
+        std::stringstream tokenStream(sqlFilter);
+        std::vector<std::string> tokens;
+
+        // Split by ' '
+        while (std::getline(tokenStream, token, ' '))
+        {
+            tokens.push_back(token);
+        }
+
+        _valid = tokens.size() == 8;
+        if (!_valid) return;
+
+        _field = tokens[5];
+        _operator = tokens[6];
+        _value = tokens[7];
+
+        // remove single quotes
+        _value = _value.substr(1, _value.size() - 2);
+
+        if (_operator == "LIKE")
+        {
+            _value = _value.substr(1, _value.size() - 2);
+        }
     }
 
-    bool StreamSql::match(const nlohmann::json& pdu)
+    bool StreamSql::valid() const
     {
-        return true;
+        return _valid;
+    }
+
+    bool StreamSql::match(const nlohmann::json& msg)
+    {
+        if (!_valid) return false;
+
+        if (msg.find(_field) == msg.end())
+        {
+            return false;
+        }
+
+        std::string value = msg[_field];
+        return value == _value;
     }
 
 } // namespace snake
diff --git a/ixsnake/ixsnake/IXStreamSql.h b/ixsnake/ixsnake/IXStreamSql.h
index 961888fc..812a2ad8 100644
--- a/ixsnake/ixsnake/IXStreamSql.h
+++ b/ixsnake/ixsnake/IXStreamSql.h
@@ -14,11 +14,16 @@ namespace snake
     class StreamSql
     {
     public:
-        StreamSql(const std::string& sqlFilter);
+        StreamSql(const std::string& sqlFilter = std::string());
         ~StreamSql() = default;
 
-        bool match(const nlohmann::json& pdu);
+        bool match(const nlohmann::json& msg);
+        bool valid() const;
 
     private:
+        std::string _field;
+        std::string _operator;
+        std::string _value;
+        bool _valid;
     };
 }
diff --git a/test/IXCobraToStdoutBotTest.cpp b/test/IXCobraToStdoutBotTest.cpp
index a4c58304..4b864206 100644
--- a/test/IXCobraToStdoutBotTest.cpp
+++ b/test/IXCobraToStdoutBotTest.cpp
@@ -92,6 +92,9 @@ TEST_CASE("Cobra_to_stdout_bot", "[cobra_bots]")
         cobraBotConfig.enableHeartbeat = false;
         bool quiet = false;
 
+        cobraBotConfig.filter =
+            std::string("select * from `") + channel + "` where id = 'sms_metric_A_id'";
+
         // We could try to capture the output ... not sure how.
         bool fluentd = true;
 
diff --git a/test/IXStreamSqlTest.cpp b/test/IXStreamSqlTest.cpp
index 6fde65a2..e14c126d 100644
--- a/test/IXStreamSqlTest.cpp
+++ b/test/IXStreamSqlTest.cpp
@@ -18,14 +18,24 @@ namespace ix
     {
         SECTION("expression A")
         {
-            snake::StreamSql streamSql("select * from subscriber_republished_v1_neo where session LIKE '%{self.session_id}%'");
+            snake::StreamSql streamSql(
+                "select * from subscriber_republished_v1_neo where session LIKE '%123456%'");
 
-            nlohmann::json msg = {
-                {"action", "auth/authenticate/error"},
-                {"id", 1},
-                {"body", {{"error", "authentication_failed"}, {"reason", "invalid secret"}}}};
+            nlohmann::json msg = {{"session", "123456"}, {"id", "foo_id"}, {"timestamp", 12}};
 
-            REQUIRE(streamSql.match(msg));
+            CHECK(streamSql.match(msg));
+        }
+
+        SECTION("expression A")
+        {
+            snake::StreamSql streamSql("select * from `subscriber_republished_v1_neo` where "
+                                       "session = '30091320ed8d4e50b758f8409b83bed7'");
+
+            nlohmann::json msg = {{"session", "30091320ed8d4e50b758f8409b83bed7"},
+                                  {"id", "foo_id"},
+                                  {"timestamp", 12}};
+
+            CHECK(streamSql.match(msg));
         }
     }