AliceO2Group · Barthelemy · Sep 13, 2018 · Sep 10, 2018 · Sep 10, 2018 · Sep 10, 2018
@@ -21,6 +21,7 @@ set(SRCS
   src/ObjectHandler.cxx
   src/Storage.cxx
   src/XmlHandler.cxx
+  src/CcdbApi.cxx
 )
 
 set(HEADERS
@@ -91,7 +92,8 @@ install(
 
 set(TEST_SRCS
    test/testWriteReadAny.cxx
-)
+   test/testCcdbApi.cxx
+) 
 
 O2_GENERATE_TESTS(
   BUCKET_NAME ${BUCKET_NAME}

@@ -1,3 +1,22 @@
+## CCDB API
+
+The CCDB API class (`CcdbApi`) is implemented using libcurl and gives
+access to the CCDB via its REST api.
+
+Usage :
+```
+// init
+CcdbApi api;
+map<string, string> metadata; // can be empty
+api.init("http://ccdb-test.cern.ch:8080");
+// store
+auto h1 = new TH1F("object1", "object1", 100, 0, 99);
+api.store(h1, "Test/Detector", metadata);
+// retrieve
+auto h1back = api.retrieve("Test/Detector", metadata);
+
+```
+
 ## Conditions MQ
 
 Conditions MQ is a client/server CCDB implementation for O2. Currently the implementation supports two backends, an OCDB and a Riak one.

@@ -0,0 +1,175 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+///
+/// \file   CcdbApi.h
+/// \author Barthelemy von Haller
+///
+
+#ifndef PROJECT_CCDBAPI_H
+#define PROJECT_CCDBAPI_H
+
+#include <string>
+#include <memory>
+#include <iostream>
+#include <map>
+#include <curl/curl.h>
+#include <TObject.h>
+
+namespace o2
+{
+namespace ccdb
+{
+
+/**
+ * Interface to the CCDB.
+ * It uses Curl to talk to the REST api.
+ *
+ * @todo use smart pointers ?
+ * @todo handle errors and exceptions
+ * @todo extend code coverage
+ */
+class CcdbApi //: public DatabaseInterface
+{
+ public:
+  /// \brief Default constructor
+  CcdbApi();
+  /// \brief Default destructor
+  virtual ~CcdbApi();
+
+  /**
+   * Initialize connection to CCDB
+   *
+   * @param host The URL to the CCDB (e.g. "ccdb-test.cern.ch:8080")
+   */
+  void init(std::string host);
+
+  /**
+   * Stores an object in the CCDB
+   *
+   * @param rootObject Shared pointer to the object to store.
+   * @param path The path where the object is going to be stored.
+   * @param metadata Key-values representing the metadata for this object.
+   * @param startValidityTimestamp Start of validity. If omitted, current timestamp is used.
+   * @param endValidityTimestamp End of validity. If omitted, current timestamp + 1 year is used.
+   */
+  void store(TObject* rootObject, std::string path, std::map<std::string, std::string> metadata,
+             long startValidityTimestamp = -1, long endValidityTimestamp = -1);
+
+  /**
+   * Retrieve object at the given path for the given timestamp.
+   *
+   * @param path The path where the object is to be found.
+   * @param metadata Key-values representing the metadata to filter out objects.
+   * @param timestamp Timestamp of the object to retrieve. If omitted, current timestamp is used.
+   * @return the object, or nullptr if none were found.
+   */
+  TObject* retrieve(std::string path, std::map<std::string, std::string> metadata,
+                    long timestamp = -1);
+
+  //    std::vector<std::string> getListOfTasksWithPublications();
+  //    std::vector<std::string> getPublishedObjectNames(std::string taskName);
+
+  /**
+   * Delete all versions of the object at this path.
+   *
+   * @todo Raise an exception if no such object exist.
+   * @param path
+   */
+  void truncate(std::string path);
+
+  /**
+   * Delete the matching version of this object.
+   *
+   * @todo Raise an exception if no such object exist.
+   * @param path Path to the object to delete
+   * @param timestamp Timestamp of the object to delete.
+   */
+  void deleteObject(std::string path, long timestamp = -1);
+
+  /**
+   * Return the listing of objects, and in some cases subfolders, matching this path.
+   * The path can contain sql patterns (correctly encoded) or regexps.
+   *
+   * In the case where there is no pattern, the list of subfolders is returned along with all the objects at
+   * this path. It does not work recursively and objects from the subfolders are not returned.
+   *
+   * In the case where there is a pattern, subfolders are not returned and any object matching the pattern will
+   * be returned, including those in subfolders if they match.
+   *
+   * Example : Task/Detector will return objects and subfolders in /Task/Detector but not the object(s) in
+   * /Task/Detector/Sub.
+   * Example : Task/Detector/.* will return any object below Detector recursively.
+   * Example : Te*e* will return any object matching this pattern, including Test/detector and TestSecond/A/B.
+   *
+   * @todo accept should use an enum class.
+   * @param path The path to the folder we want to list the children of (default : top dir).
+   * @param latestOnly In case there are several versions of the same object, list only the latest one.
+   * @param returnFormat The format of the returned string -> one of "text/plain (default)", "application/json", "text/xml"
+   * @return The listing of folder and/or objects in the format requested
+   */
+  std::string list(std::string path = "", bool latestOnly = false, std::string returnFormat = "text/plain");
+
+ private:
+  /**
+   * Get the current timestamp.
+   *
+   * @return the current timestamp as a long
+   */
+  long getCurrentTimestamp();
+  /**
+   * Transform and return a string representation of the given timestamp.
+   *
+   * @param timestamp
+   * @return a string representation of the given timestamp.
+   */
+  std::string getTimestampString(long timestamp);
+  /**
+   * Compute and return a timestamp X seconds in the future.
+   *
+   * @param secondsInFuture The number of seconds in the future.
+   * @return the future timestamp
+   */
+  long getFutureTimestamp(int secondsInFuture);
+
+  /**
+   * Build the full url to store an object.
+   *
+   * @param path The path where the object is going to be stored.
+   * @param metadata Key-values representing the metadata for this object.
+   * @param startValidityTimestamp Start of validity. If omitted or negative, the current timestamp is used.
+   * @param endValidityTimestamp End of validity. If omitted or negative, current timestamp + 1 year is used.
+   * @return The full url to store an object (url / startValidity / endValidity / [metadata &]* )
+   */
+  std::string getFullUrlForStorage(const std::string& path, const std::map<std::string, std::string>& metadata,
+                                   long startValidityTimestamp = -1, long endValidityTimestamp = -1);
+
+  /**
+   * Build the full url to store an object.
+   * @param path The path where the object is going to be found.
+   * @param metadata Key-values representing the metadata for this object.
+   * @param timestamp When the object we retrieve must be valid. If omitted or negative, the current timestamp is used.
+   * @return The full url to store an object (url / startValidity / endValidity / [metadata &]* )
+   */
+  std::string getFullUrlForRetrieval(const std::string& path, const std::map<std::string, std::string>& metadata,
+                                     long timestamp = -1);
+
+  /**
+   * Initialization of CURL
+   */
+  void curlInit();
+
+  /// Base URL of the CCDB (with port)
+  std::string mUrl;
+};
+} // namespace ccdb
+} // namespace o2
+
+#endif //PROJECT_CCDBAPI_H