Configura)on Management Founda)ons. Leonardo Gresta Paulino Murta

Transcription

1 Configura)on Management Founda)ons Leonardo Gresta Paulino Murta

2 Configura)on Item Hardware or aggrega)on subject to configura)on management Examples: CM plan Requirement Engineering Process Requirements Models Source- code of component X Etc. Leonardo Murta Configura)on Management Founda)ons 2

3 Configura)on Item The selec)on of CI should take into considera)ons basic design principles such as coupling and cohesion High coupling introduces complexity to the building process Many dependencies among CI Low cohesion introduces complexity to the development process Many developers working over the same CI CM benefits from well defined architectures Leonardo Murta Configura)on Management Founda)ons 3

4 Configura)on Item Coarse Lower System Directory Program Procedure Module Document Sec)on File Granularity Tool Demand Command Paragraph Line Perspec)ve: Code Documenta)on Fine Higher Leonardo Murta Configura)on Management Founda)ons 4

5 Derived Item A CI may be derived from other CI (source items) Example: Executable files are derived from the source code DB Schema is derived from class models Etc. CM Strategies Version control the derived items Document and version control the deriva)on process (script, tools, environment, etc.) Leonardo Murta Configura)on Management Founda)ons 5

6 Building Process that generates derived items from source items considering a target configura)on Uses automated build scripts to describe the process Example: makefile, build.xml, pom.xml The build scripts are also subject to CM Leonardo Murta Configura)on Management Founda)ons 6

7 Version Different instances of the same CI Three types of Versions: Version Revision Variant Coopera)on (Conradi and Wes_echtel 1998) Leonardo Murta Configura)on Management Founda)ons 7

8 Revisions imac genera)ons ( ) Leonardo Murta Configura)on Management Founda)ons 8

9 Variants Honda Civic Hatchback Sedan Coupe Leonardo Murta Configura)on Management Founda)ons 9

10 Coopera)on versions) Base version Peter s workspace Mary s workspace John s workspace Leonardo Murta Configura)on Management Founda)ons 10

11 versions may be merged John s workspace Mary s workspace Peter s workspace Revisions Leonardo Murta Configura)on Management Founda)ons 11

12 Conflicts may happen during merge John workspace Fred workspace Revisions Leonardo Murta Configura)on Management Founda)ons 12

13 Two other important opera)ons Diff = Patch = for storing, transferring, and comprehending versions Leonardo Murta Configura)on Management Founda)ons 13

14 Versions in the wild Mul)tude of revisions and variants altogether (set aside versions) History of Git Leonardo Murta Configura)on Management Founda)ons 14

15 But, what are versions good for? Synchronizing teamwork Reproducing previous configura)ons Exploring possibili)es Segrega)ng developers Customizing products (SPL) Tracing bug introduc)on (bisect) Understanding evolu)on (MSR) Audi)ng changes (annotate) Etc. Leonardo Murta Configura)on Management Founda)ons 15

16 CM System Version 1 Version 2 Version 3 Version 4 Version 5 Leonardo Murta Configura)on Management Founda)ons 16

17 CM System Version 1 Version 2 Version 3 Version 4 Version 5 Leonardo Murta Configura)on Management Founda)ons 17

18 CM System Version 1 Version 2 Version 3 Version 4 Version 5 Leonardo Murta Configura)on Management Founda)ons 18

19 CM System Change Requests Issue Tracking CI Version Control Build and Release Leonardo Murta Configura)on Management Founda)ons 19

20 Version Control Topology? Storage? Collabora)on? Query? CI Repository Leonardo Murta Configura)on Management Founda)ons 20

21 Topology Workspace check- in / commit Repository Workspace check- out / update push check- in Repository Repository Workspace clone / pull check- out / update Centralized Distributed Leonardo Murta Configura)on Management Founda)ons 21

22 Storage v.3 v.2 delta 2à 3 delta 1à 2 v.3 v.1 v.2/3 v.1 v.1 delta 3à 2 delta 2à 1 v.1/2 v.3 Complete Forward Reverse In-line Leonardo Murta Configura)on Management Founda)ons 22

23 Collabora)on c.3 c.2 merge merge c.1 c.1 c.1 c.2 c.3 c.2 c.3 Pessimist Optimist Mixed Leonardo Murta Configura)on Management Founda)ons 23

24 Query Repository (version 0) 1st change Repository (version 1) Ar)fact1 (version 1) Ar)fact2 (version 1) Ar)fact3 (version 1) 2nd change Repository (version 2) Ar)fact1 (version 2) Ar)fact2 (version 1) Ar)fact3 (version 1) Repository (version 3) Ar)fact1 (version 2) Ar)fact2 (version 3) Ar)fact3 (version 1) Ar)fact4 (version 3) 3rd change 4th change Repository (version 4) Ar)fact1 (version 4) Ar)fact2 (version 3) Ar)fact3 (version 4) Ar)fact4 (version 3) Query by ar)fact Ar)fact1 Version 1 Version 2 Version 4 Ar)fact2 Version 1 Version 3 Ar)fact3 Version 1 Version 4 Ar)fact4 Version 3 Leonardo Murta Configura)on Management Founda)ons 24

25 Query Repository (version 0) 1st change Repository (version 1) Ar)fact1 (version 1) Ar)fact2 (version 1) Ar)fact3 (version 1) 2nd change Repository (version 2) Ar)fact1 (version 2) Ar)fact2 (version 1) Ar)fact3 (version 1) Repository (version 3) Ar)fact1 (version 2) Ar)fact2 (version 3) Ar)fact3 (version 1) Ar)fact4 (version 3) 3rd change 4th change Repository (version 4) Ar)fact1 (version 4) Ar)fact2 (version 3) Ar)fact3 (version 4) Ar)fact4 (version 3) Query by change 1st change Ar)fact1 added Ar)fact2 added Ar)fact3 added 2nd change Ar)fact1 changed 3rd change Ar)fact2 changed Ar)fact4 added 4th change Ar)fact1 changed Ar)fact3 changed Leonardo Murta Configura)on Management Founda)ons 25

26 Query CI Change 1 * Version * 1 Ar)fact1 Version 1 Version 2 Version 4 Change 4 Ar)fact1 Ar)fact3 Leonardo Murta Configura)on Management Founda)ons 26

27 Configura)on A set of CI versions where there is one and only one version per CI A configura)on can be seen as a CI composed by other CI Examples System configura)on Process configura)on Module X configura)on Requirements configura)on Source- code configura)on Leonardo Murta Configura)on Management Founda)ons 27

28 Configura)on vs. version Version CI Composite CI Atomic CI Configura)on Generically speaking The system S is composed by CI X, Y, and Z Concretely speaking The configura)on 5 of system S is composed by version 2 of CI X, version 4 of CI Y, and version 6 of CI Z Leonardo Murta Configura)on Management Founda)ons 28

29 Tag VCS usually register mul)ple configura)ons, but just few are of interest to the user Tags allow naming such configura)ons Names can be user to indicate versions, quality levels, etc. Tags HelloWorld.java Welcome.java build.xml User.java REJECTED ACCEPTED Leonardo Murta Configura)on Management Founda)ons 29

30 Configura)on vs. version Composite CI Atomic CI Atomic CI Atomic CI Conf. 1 V.1 V.1 V.1 Conf. 2 V.2 V.2 V.2 V.3 V.3 Conf. 3 V.4 Leonardo Murta Configura)on Management Founda)ons 30

31 Baseline A specifica)on or product that has been formally reviewed and agreed upon, that therea@er serves as the basis for further development, and that can be changed only through formal change control procedures (IEEE , 1990). Baselines are created at the end of each development phase: analysis (func)onal), design (allocated) and coding (product) When is the correct moment for crea)ng baselines? Control vs. Bureaucracy Leonardo Murta Configura)on Management Founda)ons 31

32 Baseline CI changed SE Tasks CI Change Control Formal techinical reviews CI checked-out CI approved CI stored [Pressman, 1997] Baseline update process Leonardo Murta Configura)on Management Founda)ons 32

33 Baseline (levels of control) Coordina)on and audi)ng Levels of control Control Pre baseline: Informal Without request Without evalua)on Without verifica)on Agile Ad- hoc Post baseline: Formal With request With evalua)on With verifica)on Bureaucra)c Planned Leonardo Murta Configura)on Management Founda)ons 33

34 Baseline (levels of control) Baseline 1: Requirement 1 Analysis Design An. Req. 1 Baseline 2: An. Req. 1 Ds. Req. 1 An. Req. 2 Requirement 2 Analysis Design Time Req. Analysis Design Analysis Design Analysis Design 1 Inform. - Formal Inform. Formal Formal Inform. - Formal Inform. Leonardo Murta Configura)on Management Founda)ons 34

35 Release Noun: Version provided for a specific purpose Verb: Formal no)fica)on and distribu)on of a version (usually baseline) All release are versions, but not all versions are released Some)mes, releases may be developed in parallel due to time to market Examples Test release Staging release Product release Leonardo Murta Configura)on Management Founda)ons 35

36 Tags naming releases Tags HelloWorld.java Welcome.java build.xml User.java HEAD Leonardo Murta Configura)on Management Founda)ons 36

37 Branches Versions that deviate from the main development line Allow isola)on to the development process Usually reintegrated to the main development line The reintegra)on some)mes is a difficult process Workspaces (CVCS) can be seen as a temporary branch Clones (DVCS) can be seen as repository forks that may lead to branches if parallel development occurs Leonardo Murta Configura)on Management Founda)ons 37

38 Branch example Tag HelloWorld.java Welcome.java build.xml Users.java Branch 1.0.x Leonardo Murta Configura)on Management Founda)ons 38

39 Merge Help on reintegra)ng Workspaces Branches It is necessary even when pessimis)c concurrency control (lock) is in place, due to branches Automa)c algorithms categories Generic (work with all programming languages) Language Specific (take into considera)on the syntax and seman)cs of the programming language) Leonardo Murta Configura)on Management Founda)ons 39

40 Merge Types of generic merge algorithms 2- way merge 3- way merge W Y Z X Y Z W Y X Y Z W Y X or W? Y Z or nothing? X Y Leonardo Murta Configura)on Management Founda)ons 40

41 Merge Merge occurs for each CI in the branch All changes since the common ancestor are taken into considera)on 1.6 = Δ 1 + Δ 2 Δ 1 HelloWorld.java Δ 2 Leonardo Murta Configura)on Management Founda)ons 41

42 Merge Merge can be done incrementally HelloWorld.java Δ 1 Δ Δ 2 Δ 4 Leonardo Murta Configura)on Management Founda)ons 42

43 Merge Merge can be done incrementally 1.9 = Δ 3 + Δ 4 HelloWorld.java Δ 1 Δ Δ 2 Δ 4 Leonardo Murta Configura)on Management Founda)ons 43

44 Conflicts Situa)ons where it is not possible to perform automa)c merge Types Physical (line of a file) Syntac)c (elements of the file grammar) Seman)c (dependencies among elements) Current tool support focus on the physical level! Examples of physical conflicts Parallel change in the same line Parallel change and dele)on of the same line Parallel addi)ons of lines in the same file region Leonardo Murta Configura)on Management Founda)ons 44

45 Raw conflict demarca)on Leonardo Murta Configura)on Management Founda)ons 45

46 IDE conflict resolu)on Leonardo Murta Configura)on Management Founda)ons 46

47 Configura)on Management Founda)ons Leonardo Gresta Paulino Murta