Lord of the Base Image - Things every Library Supervisor should know

Transcription

1 Lord of the Base Image - Things every Library Supervisor should know Smalltalk Solutions Europe 1998 Joseph Pelrine Daedalos Consulting Group jpelrine@daedalos.de

2 About this Tutorial 16:30-18:00 PM Coffee break Beer afterwards Intermediate/Advanced Assumes you know Smalltalk and ENVY Not all answers are supplied You should want to (and be able to) figure out the implementation yourself 2

3 What We re Gonna Talk About Basic Principles Everyday Tasks Packaging and Delivery Tasks 3

4 You ll love it, it s a way of life - Frank Zappa 4

5 Basic Principles Library Architecture Image Management Tools Library Specs 5

6 Library Architecture App Views & Controllers Tools Domain Model Framework Base Support Kernel 6

7 Kernel What does it contain? The kernel contains all of the classes supplied by the vendor, together with all bug fixes and small enhancements. Who maintains it? The kernel is the responsibility of the Library Manager. This could be the mentor, local guru, or a senior smalltalker. 7

8 Base Support What does it contain? Base Support consists of all third-party base systems (run-time support, e.g. WindowBuilder runtime, add-ons for database access, etc), as well as internal system extensions and tools. Who maintains it? Either your toolsmith or your library supervisor. 8

9 Tools What does it contain? Tools consists of all internal and third-party tools which will not included in the run-time application (WindowBuilder, RDB mapping tools, etc). Who maintains it? Same as Base Support. If you have your own tools, you have someone writing them, and it's his responsibility. Otherwise the job ends up being done by the library manager. 9

10 Framework What does it contain? Internal application frameworks. Vendor-supplied or third-party frameworks (ApplicationModel or HotDraw, for example), belong in the Kernel or BaseSupport groupings. Who maintains it? If you have a large team, you probably already have a framework group. It's their responsibility. Otherwise, your best application developers, who have enough experience to keep abstracting, generalizing and refactoring these classes to make them really reuseable. 10

11 Domain Model What does it contain? Domain Objects contains all the business objects used in developing applications for a particular business.. Who maintains it? Same as Framework. Your best application developers, who have enough experience to keep abstracting, generalizing and refactoring these classes to make them really reuseable. 11

12 Application Views & Controllers What does it contain? This grouping contains all the logic necessary for a specific application, divided into smaller modules. These modules typically contain a controller and one or more views working with it. Other optional modules contains model objects needed only in the specific application, and model objects which have not yet been abstracted enough to end up in the Domain Model layer. Who maintains it? Your application developers. 12

13 Image Management Tools Make baselining easy Consistent development environment Useful in a multiple project/multiple developer environment Harmonize third-party tools Aid packaging and delivery 13

14 Image Management Tools Load All Maps Show Defined Configuration Check Defined Configuration Export Project Maps Open Editions Bad Prerequisites... 14

15 Loading ConfigMaps JPImageBuilder class>>#load: "Load an OrderedCollection of ConfigMaps" Transcript bringtofront. acollection isnil iftrue: [^false]. acollection do: [:each each notnil iftrue: [ Transcript cr; show: -> Loading ConfigurationMap: ; show: each signature; show:.... each beenloaded: false. each load. (self beenloaded: each) iffalse: [^false]. Transcript show: LOADED ]]. Transcript cr; show: DONE. ^true 15

16 Loading ConfigMaps The ConfigMaps for each layer are defined in a method Definitions could be stuffed into User Fields, but you have no version history Usable for multiple projects "Coffee Break" tool What do you save in the methods? 16

17 LibrarySpecs Thanks to Jan Steinmann ConfigMaps Applications/SubApplications Classes Methods 17

18 Library Spec #(rootname appname) #(rootname appname {timestamp classname}) #(rootname appname classname {timestamp selector}) #(rootname appname classname selector timestamp) 18

19 EmConfigurationMap class>>fromlibraryspec: alibraryspecarray "Return the ConfigMap edition described by this library spec, or nil. Note - this is not the complete implementation!" ^(self editionsdictionaryfor: (alibraryspecarray at: 2)) detect: [:shdw shdw timestamp = (alibraryspecarray at: 3)] ifnone: [^nil] EmConfigurationMap>>librarySpec ^Array with: self class name with: self name with: self timestamp libraryspec EmTimeStamp>>librarySpec "Answer my second count." ^seconds 19

20 I hated it until I loved it????? 20

21 Everyday Tasks Writing Scripts Changing defaults Customizing browsers Tools 21

22 Writing Scripts Useful for everyday tasks Can be easily packed into methods Require prompters knowledge of ENVY protocol 22

23 Prompter Utility #chooseauser #chooseanappandedition #chooseanconfigmapandedition #choosesomeapps #choosesomeappsandeditions #choosesomeconfigmapsandeditions 23

24 A Sample Script Adding a User Defining a new user is easy But then, you have to include him/her as a group member in all Applications the he/she will be working on A script takes away the grunt work 24

25 #chooseauser chooseauser "self chooseauser" ^EtTools promptforuser: Choose a User 25

26 #choosesomeapps choosesomeapps "self choosesomeapps" ^EtBrowser new prompt: Select some Apps choosemultiplefrom: (Application currentlyloaded assortedcollection: Class sortblock) initialselection: nil printblock: nil statusindicatorblock: nil 26

27 Script Example "Add a user to an bunch of apps" user apps user := JPPrompterUtility chooseauser. apps := JPPrompterUtility choosesomeapps. apps do: [ :app JPPrompterUtility changeuserto: app manager while: [app addgroupmember: user]] 27

28 #choosesomeconfigmapsandeditions choosesomeconfigmapsandeditions "self choosesomeconfigmapsandeditions" ^EtConfigurationMapsBrowser new prompt: Select the configuration map versions choosemultiplefrom: EmConfigurationMap configurationmapnames assortedcollection label: Names printblock: [:mapname mapname] dependentlistblock: [:mapname (EmConfigurationMap editionsfor: mapname) asarray select: [:edition edition isversion]] dependentlabel: Versions dependentprintblock: [:map map timestamp signature] selectedlabel: Selected Versions selectedprintblock: [:map map signature] statusindicatorblock: nil 28

29 Changing Defaults Error Reporter Manager Interface Browsers 29

30 Error Reporter Central interface for all error reporting EmImageSupport errorreporter: EmErrorReporter new initialize Interesting messages to override: #logerror:withparms:severity: #reporterror:withparms:severity: You could also substitute the log device and the report device in the current error reporter 30

31 Manager Interface Supplies version names EmInterface current 31

32 Manager Interface - 2 Application subclass: #JPManagerInterfaceApp instancevariablenames: classvariablenames: OldLibraryInterface pooldictionaries: EmInterface subclass: #JPManagerInterface instancevariablenames: classvariablenames: pooldictionaries: install "install the customized Manager Interface when loaded" self istoolinstalled iffalse: [ OldLibraryInterface := JPManagerInterface current. JPManagerInterface current: JPManagerInterface new] deinstall "reinstal the default (or previous) Manager Interface when removing" self istoolinstalled iftrue: [JPManagerInterface current: (OldLibraryInterface == nil iftrue: [JPManagerInterface superclass new] iffalse: [OldLibraryInterface])] istoolinstalled "answer true, if the new interface is installed" ^JPManagerInterface current class == JPManagerInterface 32

33 Version Name Protocol Use a different incrementing algorithm Enforce company standards Add User initials V [JP ] Do you really want initials? Version name templates (StS) 33

34 User Initials EmUser>>initials initials (initials := self record inheriteduserfieldat: #Initials) isempty iftrue: [self initials: self createinitials]. ^initials EmUser>>initials: astring self updaterecordwith: [:record record inheriteduserfieldat: #Initials put: astring]. ^astring EmUser>>createInitials ^self fullname select: [:c c isuppercase] 34

35 Browsers Image Application Manager Repository Application Configurations Configuration Maps 35

36 Browsers Default browser mappings are stored in EtTools browsermappings You can subclass existing browsers and install them as default mappings Each user can store custom changes either in extension Applications or in User Fields EtWindow class>>#defaultwindowsize: 36

37 EtToolsVendorExtensionApp Allows extensions to menus without changing existing code Simple Protocol #addtoapplicationsmenu:browser: #addtoclassesmenu:browser: #addtomethodsmenu:browser: #addtotextmenu:browser: Public domain Existing tools easily adaptable 37

38 Browsers -Extension or Subclass? Changes made through extensions are available to all normal browser subclasses, but are trickier to implement Changes made in subclasses can be more extreme, but must be reimplemented in all browsers wanting them Extend when possible 38

39 Stupid Mistakes I Have Made Not allowing compilation when Warning 49 occurs Forcing Application comments upon versioning Forcing Class versioning ("Junk") when reloading current Application and many others 39

40 Library Supervisor Is God Mode Saves a lot of time!! Shouldn't be available to all A lot of work to implement It's better to subclass EtApplicationManager for this than to extend it 40

41 Changing Users changeuserto: newuser while: ablock olduser (olduser := EmUser current) = newuser iftrue: [^ablock value]. (EmUser classpool declarevariable: CurrentUser ) value: newuser. ^ablock ensure: [ (EmUser classpool declarevariable: CurrentUser ) value: olduser] 41

42 Package early, package often 42

43 Packaging & Delivery Tasks Renaming Versions Sorting Out Prerequisites Refactoring Prerequisites Moving SubApps 43

44 Renaming Versions Thanks to Eric Clayberg Murphy's law of software versioning Especially useful for toolsmiths Kids, don't try this at home!! 44

45 Renaming Application Versions hods: EtApplicationManager>>renameApplicationVersions Rename the selected application versions newname newname := self prompt: 'Enter new version name' answer: self selectedapplication newname. (newname isnil or: [newname isempty]) iftrue: [^self]. self execshortoperation: [ self selectedapplications do: [:application application timestamp newname = newname iffalse: [ application updateedition: [:editionrecord editionrecord setnewname: newname; insert]]]. self redrawapplications] 45

46 Renaming Class Versions EtApplicationManager>>renameClassVersions application timestamp newname application := self selectedapplication. timestamp := self selectedclass timestampin: application. newname := self prompt: Enter new version name answer: timestamp newname. (newname isnil or: [newname isempty]) iftrue: [^self]. self execshortoperation: [ self selectedclasses do: [:class class ismetaclass iffalse: [ timestamp := class timestampin: application. timestamp newname = newname iffalse: [ timestamp newname: newname. class updatein: application with: [:editionsrecord entry oldlength entry := editionsrecord currententry. oldlength := entry newname size. entry replaceelement: 2 with: newname; length: entry length - oldlength + newname size; yourself]]]]. self redrawclasses] 46

47 Renaming Configuration Map Versions EtConfigurationMapBrowser>>renameConfigMapVersions edition versionname self changerequest iffalse: [^self]. edition := self selectededition. versionname := self prompt: Enter new version name for, edition signature answer: edition versionname. (versionname isnil or: [versionname isempty]) iftrue: [^nil]. self execshortoperation: [ self selectededition relocaterecordwith: [:editionrecord editionrecord replaceelement: 2 with: versionname; insert]. self updateeditions: self selectededitions restoretotop: true] 47

48 Run-time dependencies - just say no! 48

49 Sorting Out Prerequisites Don t ignore Warning 49 The method which has just been compiled references a class which it shouldn't. This is because the class referenced is not "visible" in the prerequisite chain of the application containing the method. This can be corrected in two ways: You can move the method to another application which has the class in its prerequisite chain. You can move the class to make it visible, by including the class's defining application into the prerequisite chain for the method's application First you have to find out where something's wrong 49

50 Prerequisites Browser Thanks to Glenn Jones 50

51 SubApplication class>>#badprerequisiteclasses Transcript bringtofront; cr; show: Looking for missing prerequisite classes in, self symbol. self badprerequisiteclassesdictionary associationsdo: [:each Transcript cr; show: each key printstring, ( ; show: each key methodclass controller name, ) references:. (each value assortedcollection: Class sortblock) do: [ :class Transcript cr; show:, class name, ( ; show: class controller name, ) ]]. Transcript cr; show: done ; cr. 51

52 SubApplication class>>#badprerequisiteclassesdictionary "Returns a dictionary of methods that reference classes not defined in prerequisite applications" nonprereq visibleclasses collection allapplications nonprereq := IdentityDictionary new. allapplications := self withallsubapplications. visibleclasses := app allvisibleclasses. allapplications do: [ :app app visiblepublicclasses do: [ :class (class methodsin: app) do: [ :method method do: [ :literal ((literal isassociation) and: [literal value isclass]) iftrue: [ (literal value = app) iffalse: [ (visibleclasses includes: literal value controller) iffalse: [ (nonprereq at: method ifabsentput: [OrderedCollection new]) add: literal value]]]]]]]. ^nonprereq 52

53 Refactoring Prerequisites Although it is not needed by a specific application, a prerequisite can not be removed if it is required by a dependent of the application 53

54 How to do it Version and release any open class editions You re going to reload the current (released) lineup Browse Application Editions Remove the prereq Add the prereq From the AppMan, choose both, then reload current 54

55 Moving SubApps on the fly Most times it's not possible to unload and reload Applications independently because of 'prerequisite gridlock' This is another manipulation which must be done in the repository and not in the image 55

56 How to do it Version and release any open class editions You re going to reload the current (released) lineup Browse Application Editions Remove the SubApp Add the SubApp From the AppMan, choose both, then reload current 56

57 Resources st- Smalltalk Report VisualAge Magazine comp.lang.smalltalk 57

58 Thanks OTI, for the tool Kent Beck, Stefan Bosshard, Eric Clayberg, Glenn Jones, Alan Knight, Jan Steinman, all the guys at Daedalos, Peter Misch and Renate Schirmer 58