Diploma Thesis Santiago GÃ³mez SÃ¡ez - IAAS

More documents

Recommendations

Info

6. Implementation the bundle activation process, the OSGi container creates one instance of the class which implements the BundleActivator interface, and executes its operations. The class OSGIHandler of the MySQL Proxy OSGi bundle implements those operations, and allows us to instantiate the classes which are used in the component, its properties, and the references to third party OSGi bundles. Furthermore, it loads the server properties file from the bundle package. The instantiation of Java classes packed in third party bundles can be done by looking up the associated bundle service in the OSGi registry. The lookup can be done either by accessing with Java code the BundleContext operations (see Listing 6.1), or using Spring functionalities. Spring enables the properties setting and the external bundle reference in XML format (see Listing 6.1), in the beans.xml file. We utilize this feature to reference to the following OSGi bundles: the NMR API shipped with ServiceMix, and the JBI ServiceMix Registry developed by Uralov [Ura12]. 1 -- Spring -- 2 3
6.1. SQL Support Implementation For each connection accepted in the server thread, an instance of a protocol handler is created. We highly recommend to utilize the MySQL client native driver MySQL Connector/J mysql-connector-java-5.1.22-bin.jar, as we follow the MySQL protocol it implements in this component. The ConnectionHandler is implemented as a Java interface, in order to allow future extensibility for different database server protocols. In this diploma thesis we provide support for the MySQL communication protocol. However, we do not recommend to implement a multiple protocol support in the component. The server thread listens to one specific port, and this fact may lead with conflicts between the protocols or the classes which implement the protocol support. Furthermore, a change or upgrade of a specific protocol would involve the redeployment of the component, and a service outage of all the protocols supported. The system resources consumption, e.g. Java heap memory or CPU, is limited for each bundle in the OSGi container, and may lead to scalability problems with the maximum number of concurrent threads in the pool. We recommend to implement the different database server communication protocols in independent OSGi components, but profiting from the resources sharing support for common resources, e.g. cache, in the OSGi container. Each Connection- Handler instance creates a ProtocolHandler. The ProtocolHandler class groups the support for the MySQL communication protocol phases: connection, authentication, command, and termination (see Section 2.9). The internal server states are defined as waiting, sent server greeting, and command processing. During the waiting phase, the server waits for the client’s MySQL packet to arrive. In the send server greeting phase, the MySQL server greeting is sent to the client, and the server waits for the authentication challenge response. When the authentication is successful, the server is in the command phase. The command phase groups the interpretation of the request, verification of the tenant and user information, message transfer to the CDASMixjdbc component, and the transmission of the MySQL response via the TCP socket created by the client. The logic of the query processing is located in the method processQuery. This method receives the SQL query contained in the MySQL packet, and processes it. The processing of the query is divided into the following activities: classification, meta-data retrieval, meta-data construction, and response transfer. The classification of queries is fundamental in a system which provides cashing functionalities. We differentiate the received queries as server configuration queries, data retrieval queries, and database modification queries. In the first group we classify the queries which are related to the specific server configuration that a MySQL client requires. This queries must be directly executed in the backend SQL Cloud data store. Therefore, they are forwarded directly to the CDASMixjdbc component. The data retrieval queries involve those that read the data stored in a database. The response to this queries is cached in order to read them directly from the cashing component in a close future. The database modification queries perform modification on the backend Cloud data stores, such as table creation, row update, or row insertion. These cannot be cached, but the entries in the cache which contain data related to the modified tables are invalidated. The meta-data of the user’s request is retrieved from the mysqlproxy.registry package, which includes information about the target database, access credentials, etc. Multi-querying processing is supported in the prototype, allowing users to include in one execution statement more than one query. For 65
Page 1:
Institute of Architecture of Applic
Page 5 and 6:
Contents 1. Introduction 1 1.1. Pro
Page 7 and 8:
Contents 7.3.3. Evaluation Analysis
Page 9 and 10:
List of Figures 1.1. Migration Scen
Page 11 and 12:
List of Tables 4.1. Description of
Page 13:
List of Listings 5.1. Tenant-aware
Page 16 and 17:
1. Introduction and multi-protocol
Page 18 and 19:
1. Introduction Definitions List of
Page 20 and 21:
1. Introduction • Implementation,
Page 22 and 23:
2. Fundamentals usage of it. PaaS p
Page 24 and 25:
2. Fundamentals 2.2.1. Enterprise S
Page 26 and 27:
2. Fundamentals through the network
Page 28 and 29: Management Framework Component Fram
Page 30 and 31: 2. Fundamentals corresponding works
Page 32 and 33: 2. Fundamentals the tenant level, b
Page 34 and 35: 2. Fundamentals 2.9. Structured Que
Page 36 and 37: 2. Fundamentals 2.9.2. PostgreSQL D
Page 38 and 39: 2. Fundamentals 2.10.1. Key-value D
Page 40 and 41: 2. Fundamentals User Interface Web
Page 42 and 43: 28 2. Fundamentals
Page 44 and 45: 3. Related Works and balancing the
Page 46 and 47: 3. Related Works store may contain
Page 48 and 49: 3. Related Works In the second plac
Page 50 and 51: 4. Concept and Specification VM0 or
Page 52 and 53: 4. Concept and Specification then f
Page 54 and 55: 4. Concept and Specification 4.3. D
Page 56 and 57: 4. Concept and Specification 4.6. U
Page 58 and 59: 4. Concept and Specification Name G
Page 60 and 61: 4. Concept and Specification Name G
Page 62 and 63: 4. Concept and Specification 4.8.3.
Page 64 and 65: 5. Design stores have two main stor
Page 66 and 67: 5. Design userId serviceName XMLNam
Page 68 and 69: 5. Design received in the vendor’
Page 70 and 71: 5. Design JBI SA into an OSGi conta
Page 72 and 73: 5. Design Apache Camel provides a s
Page 74 and 75: 5. Design External Application Lege
Page 76 and 77: 5. Design External Application Exte
Page 80 and 81: 6. Implementation each of the queri
Page 82 and 83: 6. Implementation multi-tenancy awa
Page 84 and 85: 6. Implementation The HTTP endpoint
Page 86 and 87: 6. Implementation stored. Both auth
Page 88 and 89: 74 6. Implementation
Page 90 and 91: 7. Validation and Evaluation We mus
Page 92 and 93: 7. Validation and Evaluation When t
Page 94 and 95: 7. Validation and Evaluation in the
Page 96 and 97: 1. Introduction 1. Introduction 7.
Page 98 and 99: 7. Validation and Evaluation proble
Page 100 and 101: 7. Validation and Evaluation access
Page 102 and 103: 8. Outcome and Future Work The func
Page 104 and 105: 90 8. Outcome and Future Work
Page 106 and 107: Appendix A. Components A.2. CDASMix
Page 108 and 109: 94 Appendix A. Components
Page 110 and 111: Appendix B. Messages 20 - target da
Page 112 and 113: Appendix B. Messages 110 111 - OK r
Page 114 and 115: Appendix B. Messages 1 interface: l
Page 116 and 117: 102 Appendix B. Messages
Page 118 and 119: Bibliography [CC06] F. Chong and G.
Page 120 and 121: Bibliography [SAS + 12] [SBK + 12]
Page 122 and 123: Acknowledgement I am heartily thank
show all

Diploma Thesis Santiago GÃ³mez SÃ¡ez - IAAS

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?