Throw custom exceptions (awegrzyn#52)

* init work on exception handling

* use internal except class

* Cover factory failures

* Improv query test

* throw when db not specified

* Use make test

* Provide basic docs

Author: awegrzyn

.travis.yml

@@ -28,10 +28,7 @@ script:
   - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then cmake ..;
     else cmake .. -DCMAKE_C_COMPILER=/usr/bin/gcc-7 -DCMAKE_CXX_COMPILER=/usr/bin/g++-7 -DCMAKE_BUILD_TYPE=Debug; fi;
   - make -j
-  - influx -database "test" -execute "select * from test"
-  - ./bin/testHttp
-  - influx -database "test" -execute "select * from test"
-  - ./bin/testQuery
+  - make test
 after_success:
   - |
     if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then

CMakeLists.txt

@@ -115,6 +115,7 @@ if (Boost_FOUND)
     test/testPoint.cxx
     test/testHttp.cxx
     test/testQuery.cxx
+    test/testFactory.cxx
   )
 
   foreach (test ${TEST_SRCS})

README.md

@@ -5,7 +5,6 @@
 
 
 InfluxDB C++ client library
- - Writing points
  - Batch write
  - Data exploration
  - Supported transports

include/InfluxDBFactory.h

@@ -22,6 +22,9 @@ class InfluxDBFactory
    InfluxDBFactory(const InfluxDBFactory&) = delete;
 
    /// InfluxDB factory
+   /// Provides InfluxDB instance with given transport
+   /// \param url 	URL defining transport details
+   /// \throw InfluxDBException 	if unrecognised backend or missing protocol
    static std::unique_ptr<InfluxDB> Get(std::string url) noexcept(false);
 
  private:

src/HTTP.cxx

@@ -3,6 +3,7 @@
 ///
 
 #include "HTTP.h"
+#include "InfluxDBException.h"
 #include <iostream>
 
 namespace influxdb
@@ -20,11 +21,14 @@ void HTTP::initCurl(const std::string& url)
 {
   CURLcode globalInitResult = curl_global_init(CURL_GLOBAL_ALL);
   if (globalInitResult != CURLE_OK) {
-    throw std::runtime_error(std::string("cURL init") + curl_easy_strerror(globalInitResult));
+    throw InfluxDBException("HTTP::initCurl", curl_easy_strerror(globalInitResult));
   }
 
   std::string writeUrl = url;
   auto position = writeUrl.find("?");
+  if (position == std::string::npos) {
+     throw InfluxDBException("HTTP::initCurl", "Database not specified");
+  }
   if (writeUrl.at(position - 1) != '/') {
     writeUrl.insert(position, "/write");
   } else {
@@ -71,7 +75,7 @@ std::string HTTP::query(const std::string& query)
   curl_easy_setopt(readHandle, CURLOPT_WRITEDATA, &buffer);
   response = curl_easy_perform(readHandle);
   if (response != CURLE_OK) {
-    throw std::runtime_error(curl_easy_strerror(response));
+    throw InfluxDBException("HTTP::query", curl_easy_strerror(response));
   }
   return buffer;
 }
@@ -106,10 +110,10 @@ void HTTP::send(std::string&& post)
   response = curl_easy_perform(writeHandle);
   curl_easy_getinfo(writeHandle, CURLINFO_RESPONSE_CODE, &responseCode);
   if (response != CURLE_OK) {
-    throw std::runtime_error(curl_easy_strerror(response));
+    throw InfluxDBException("HTTP::send", curl_easy_strerror(response));
   }
   if (responseCode < 200 || responseCode > 206) {
-    throw std::runtime_error("Response code : " + std::to_string(responseCode));
+    throw InfluxDBException("HTTP::send", "Response code: " + std::to_string(responseCode));
   }
 }
 

src/HTTP.h

@@ -26,9 +26,11 @@ class HTTP : public Transport
     ~HTTP();
 
     /// Sends point via HTTP POST
+    ///  \throw InfluxDBException	when CURL fails on POSTing or response code != 200
     void send(std::string&& post) override;
 
     /// Queries database
+    /// \throw InfluxDBException	when CURL GET fails
     std::string query(const std::string& query) override;
 
     /// Enable Basic Auth
@@ -39,8 +41,11 @@ class HTTP : public Transport
     void enableSsl();
   private:
 
-    /// Initilizes CURL and all common options
+    /// Initilizes CURL for writting and common options
+    /// \throw InfluxDBException	if database (?db=) not specified
     void initCurl(const std::string& url);
+
+    /// Initializes CURL for reading
     void initCurlRead(const std::string& url);
 
     /// CURL pointer configured for writting points

src/InfluxDB.cxx

@@ -3,6 +3,7 @@
 ///
 
 #include "InfluxDB.h"
+#include "InfluxDBException.h"
 
 #include <iostream>
 #include <memory>
@@ -119,7 +120,7 @@ std::vector<Point> InfluxDB::query(const std::string&  query)
 #else
 std::vector<Point> InfluxDB::query(const std::string& /*query*/)
 {
-  throw std::runtime_error("InfluxDB query() requires boost");
+  throw InfluxDBException("InfluxDB::query", "Boost is required");
 }
 #endif
 

src/InfluxDBException.h

@@ -0,0 +1,24 @@
+///
+/// \author Adam Wegrzynek <adam.wegrzynek@cern.ch>
+///
+
+#ifndef INFLUXDATA_EXCEPTION_H
+#define INFLUXDATA_EXCEPTION_H
+
+#include <stdexcept>
+#include <string>
+
+namespace influxdb
+{
+
+class  InfluxDBException: public std::runtime_error
+{
+
+public:
+  InfluxDBException(const std::string& source, const std::string& message)
+    : std::runtime_error::runtime_error("influx-cxx [" + source + "]: " + message) {}
+};
+
+} // namespace influxdb
+
+#endif // INFLUXDATA_EXCEPTION_H

src/InfluxDBFactory.cxx

@@ -6,16 +6,17 @@
 #include <functional>
 #include <string>
 #include <memory>
+#include <map>
 #include "UriParser.h"
 #include "HTTP.h"
-#include <map>
+#include "InfluxDBException.h"
 
 #ifdef INFLUXDB_WITH_BOOST
 #include "UDP.h"
 #include "UnixSocket.h"
 #endif
 
-namespace influxdb 
+namespace influxdb
 {
 
 #ifdef INFLUXDB_WITH_BOOST
@@ -28,11 +29,11 @@ std::unique_ptr<Transport> withUnixSocketTransport(const http::url& uri) {
 }
 #else
 std::unique_ptr<Transport> withUdpTransport(const http::url& /*uri*/) {
-  throw std::runtime_error("UDP transport requires Boost");
+  throw InfluxDBException("InfluxDBFactory", "UDP transport requires Boost");
 }
 
 std::unique_ptr<Transport> withUnixSocketTransport(const http::url& /*uri*/) {
-  throw std::runtime_error("Unix socket transport requires Boost");
+  throw InfluxDBException("InfluxDBFactory", "Unix socket transport requires Boost");
 }
 #endif
 
@@ -58,12 +59,12 @@ std::unique_ptr<Transport> InfluxDBFactory::GetTransport(std::string url) {
 
   http::url parsedUrl = http::ParseHttpUrl(url);
   if (parsedUrl.protocol.empty()) {
-    throw std::runtime_error("Ill-formed URI");
-  }   
+    throw InfluxDBException("InfluxDBFactory::GetTransport", "Ill-formed URI");
+  }
 
   auto iterator = map.find(parsedUrl.protocol);
   if (iterator == map.end()) {
-    throw std::runtime_error("Unrecognized backend " + parsedUrl.protocol);
+    throw InfluxDBException("InfluxDBFactory::GetTransport", "Unrecognized backend " + parsedUrl.protocol);
   }
 
   return iterator->second(parsedUrl);

src/UDP.cxx

@@ -3,6 +3,7 @@
 ///
 
 #include "UDP.h"
+#include "InfluxDBException.h"
 #include <string>
 
 namespace influxdb
@@ -21,7 +22,11 @@ UDP::UDP(const std::string &hostname, int port) :
 
 void UDP::send(std::string&& message)
 {
-  mSocket.send_to(boost::asio::buffer(message, message.size()), mEndpoint);
+  try {
+    mSocket.send_to(boost::asio::buffer(message, message.size()), mEndpoint);
+  } catch(const boost::system::system_error& e) {
+    throw InfluxDBException("UDP::send", e.what());
+  }
 }
 
 } // namespace transports

src/UnixSocket.cxx

@@ -3,6 +3,7 @@
 ///
 
 #include "UnixSocket.h"
+#include "InfluxDBException.h"
 #include <string>
 
 namespace influxdb
@@ -19,7 +20,11 @@ UnixSocket::UnixSocket(const std::string &socketPath) :
 
 void UnixSocket::send(std::string&& message)
 {
-  mSocket.send_to(boost::asio::buffer(message, message.size()), mEndpoint);
+  try {
+    mSocket.send_to(boost::asio::buffer(message, message.size()), mEndpoint);
+  } catch(const boost::system::system_error& e) {
+    throw InfluxDBException("UnixSocket::send", e.what());
+  }
 }
 #endif // defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)
 

test/testFactory.cxx

@@ -0,0 +1,23 @@
+#define BOOST_TEST_MODULE Test InfluxDB Factory
+#define BOOST_TEST_DYN_LINK
+#include <boost/test/unit_test.hpp>
+
+#include "../include/InfluxDBFactory.h"
+#include "../src/InfluxDBException.h"
+
+namespace influxdb {
+namespace test {
+
+
+BOOST_AUTO_TEST_CASE(unrecognisedBackend)
+{
+  BOOST_CHECK_THROW(influxdb::InfluxDBFactory::Get("httpz://localhost:8086?db=test"), InfluxDBException);
+}
+
+BOOST_AUTO_TEST_CASE(missformatedUrl)
+{
+  BOOST_CHECK_THROW(influxdb::InfluxDBFactory::Get("localhost:8086?db=test"), InfluxDBException);
+}
+
+} // namespace test
+} // namespace influxdb

test/testHttp.cxx

@@ -3,6 +3,7 @@
 #include <boost/test/unit_test.hpp>
 
 #include "../include/InfluxDBFactory.h"
+#include "../src/InfluxDBException.h"
 
 namespace influxdb {
 namespace test {
@@ -27,5 +28,16 @@ BOOST_AUTO_TEST_CASE(write1)
     .addTag("host", "localhost"));
 }
 
+BOOST_AUTO_TEST_CASE(writeWrongHost)
+{
+  auto influxdb = influxdb::InfluxDBFactory::Get("http://localhost2:8086?db=test");
+  BOOST_CHECK_THROW(influxdb->write(Point{"test"}.addField("value", 10)), InfluxDBException);
+}
+
+BOOST_AUTO_TEST_CASE(writeNoDb)
+{
+  BOOST_CHECK_THROW(influxdb::InfluxDBFactory::Get("http://localhost:8086"), InfluxDBException);
+}
+
 } // namespace test
 } // namespace influxdb

test/testQuery.cxx

@@ -12,7 +12,7 @@ namespace test {
 BOOST_AUTO_TEST_CASE(query1)
 {
   auto influxdb = influxdb::InfluxDBFactory::Get("http://localhost:8086?db=test");
-  auto points = influxdb->query("SELECT * from test LIMIT 3");
+  auto points = influxdb->query("SELECT * from test WHERE host = 'localhost' LIMIT 3");
   BOOST_CHECK_EQUAL(points[0].getName(), "test");
   BOOST_CHECK_EQUAL(points[1].getName(), "test");
   BOOST_CHECK_EQUAL(points[2].getName(), "test");