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Posted to commits@tapestry.apache.org by hl...@apache.org on 2007/01/17 04:38:17 UTC
svn commit: r496924 - in
/tapestry/tapestry5/tapestry-project/trunk/src/site/resources:
tap5devwiki.html tap5devwiki.xml
Author: hlship
Date: Tue Jan 16 19:38:16 2007
New Revision: 496924
URL: http://svn.apache.org/viewvc?view=rev&rev=496924
Log:
Add ideas about total reloading
Modified:
tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.html
tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.xml
Modified: tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.html
URL: http://svn.apache.org/viewvc/tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.html?view=diff&rev=496924&r1=496923&r2=496924
==============================================================================
--- tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.html (original)
+++ tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.html Tue Jan 16 19:38:16 2007
@@ -5179,10 +5179,11 @@
<div tiddler="EnvironmentalServices" modifier="HowardLewisShip" modified="200609260145" created="200609251547" tags="">Frequently, different components need to //cooperate// during the rendering process.\n\nThis is an established pattern from Tapestry 4, which an enclosing component provides services to the components it encloses. By //encloses// we mean, any components that are rendered as part of the Form's body; give the use of the Block/~RenderBlock components, this can not be determined statically, but is instead determined dynamically, as part of the rendering process.\n\nThe canoncial example of this pattern is Form component, and the complex relationship it has with each form element component it encloses.\n\nIn Tapestry 4, this mechanism was based on the ~IRequestCycle which could store named attributes. The service providing component would store itself into the cycle using a well known name, and service consuming components would retrieve the service using the sam
e well known name.\n\nFor Tapestry 5, this will be formalized. A new service will be used to manage this information:\n\n{{{\npublic interface Enviroment\n{\n <T> T push(Class<T> type, T instance);\n\n <T> peek(Class<T> type);\n\n <T> T pop(Class<T> type);\n}\n}}}\n\nThe Environment is unique to a request.</div>
<div tiddler="FocusOnTesting" modifier="HowardLewisShip" modified="200611241954" created="200611241954" tags="">I'm still not at the stage of test first, but with every line of code I write, I am thiking about how I will test that line of code. Tapestry uses EasyMock extensively, and there's lots of existing code examples to work with.\n\n!Dont Despair\n\nI occasionally get exhausted by the amount of test code I write for simple chunks of code. And I inevitably find a broken line of code that would be a major pain to locate inside a running application, but easy inside a unit test. Keep your eyes on the big picture.</div>
<div tiddler="FormProcessing" modifier="HowardLewisShip" modified="200609211540" created="200609210203" tags="forms">Form processing in Tapestry 4 had certain strengths and limitations.\n\nBasically, any action framework that can do a simple mapping from query parameters to bean property names has advantages in terms of simple forms, and Tapestry 4's approach has huge advantages on more complex forms (with some considerable developer and framework overhead).\n\nWith a direct mapping of query parameter names to bean names, each query parameter becomes self describing. You map query parameters to property of some well known bean. You do simple conversions from strings to other types (typically, ints and dates and the like). You drop query parameters that don't match up. You leave a lot of validation and other plumbing (such as getting those values into your DataTransferObjects) to the developer.\n\nBut you never see a ~StaleLinkException.\n\nYou also have some unwanted loophol
es in your application in that //any// property can be updated through the URL. This is //one step// towards a security hole.\n\n!Tapestry 4 Approach\n\nEvery form component, as it renders, asks the Form that encloses it to provide a client id. The terminology is a little messed; client id is the unique (within the form) name for //one rendering// of the component. If the component renders multiple times, because of loops, each rendering gets a unique name. This becomes the <input>'s name attribute, and ultimately, the query parameter name.\n\nTapestry attempts to make the client id match the (user provided) component id. This is not always possible, especially in a loop, in which case a numeric suffix may be appended to the id to (help) ensure uniqueness.\n\nOn render, a sequence of //component activations// occur, guided by the normal render sequence. The exact sequence of activations guides\nthe production of client ids.\n\nUsing more advanced Tapestry techniques,
including loops, conditionals and the Block/RenderBlock combo, the exact set of components and\ncomponent activations that will occur for a given rendering of a given form can not be predicted statically. Tapestry must actually render out the form\nto discover all of these.\n\nIn fact, while the Form component is producing this series of client ids, it builds up the list and stores it into the rendered page as a hidden form field. It will need it later, when the client-side form is submitted back to the server.\n\nAn advantage of this approach is the disconnect between the query parameter names (the client ids) and the objects and properties being editted. Often the client ids will be //mneumonic// for the properties, but aren't directly mapped to them. Only the components responsible for each query parameter know how to validate the submitted value, and what property of which object will need to be updated.\n\nWhen a form submission occurs, we want to ensure that each quer
y parameter value read out of the request is applied to the correct property of the correct object. There's a limit to how much Tapestry can help here (because it has only a casual knowledge of this aspect of the application structure).\n\nDuring this submission process, which endded up with the curious name, //rewind phase//, Tapestry must do two things:\n* Activate each component, such that the component may re-determine its client id, read its parameter, and update its page property\n* Validate that the process has not been comprimised by a change of server side state\n\nThat second element is a tricky one; things can go wonky if a race condition occurs between two users. For example, lets take a simple invoice and line item model. If users A and B both read the same invoice, user A adds a line item, and user B changes a line item ... we can have a problem when user B submits the form. Now that there are three line items (not two) in the form, there will be extra componen
t activations to process query parameters that don't exist in the request. \n\nThis scenario can occur whenever the processing of the form submission is driven by server-side data that can change between request.\n\nTapestry detects this as a difference in the sequence of client ids allocated, and throws a ~StaleLinkException, which is very frustrating for developers to comprehend and fix.\n\nThere are also other edge cases for different race conditions where data is applied to the wrong server-side objects.\n\nThe Tapestry 3 ~ListEdit component, which evolved into the Tapestry 4 For component, attempts to address this by serializing a series of //object ids// into the form (as a series of hidden fields). This requires a bit of work on the part of the developer to provide an ~IPrimaryKeyConverter that can help convert objects to ids (when rendering) and ids back to objects (during form submission).\n\nGenerally speaking, the Tapestry 4 approach represents layers of kludge o
n layers of kludge. It works, it gets the job done, it can handle some very complex situations, but it is less than ideal.\n\n!Tapestry 5\n\nThe goal here is to capture the series of //component activations//, along with any significant page state changes, during the render.\n\nThese activations will be a series of //commands//. For each component activation there will be two commands: the first command will be used to inform the component of its client id (this command executes during render and during form submission). The second command will request that the client handle the form submission (this command executes only during form submission).\n\nThe serialized series of commands is stored as a hidden form field.\n\nThere's a lot of API to be figured out, especially the relationship between the form components and the form itself.\n\nFurther, a lot of what the Tapestry 4 For component does, in terms of serializing dynamic page state, will need to fold into this as well.
\n\nThe end result will be a single hidden field with a big MIME string inside it ... but compared to the Tapestry 4 Form component (which has to write out many hidden fields) the whole will be less than the sum of the parts ... due to the overhead of serialization and gzip compression.\n\n\n\n\n\n\n</div>
+<div tiddler="FullReload" modifier="HowardLewisShip" modified="200701161450" created="200701161450" tags="">It has occured to me that by adding yet another smart class loader, we could possibly set up a system where we track date time modified on all the modules, service interfaces, and implementation files loaded by the Registry, such that changes to any of the files could result in a kind of "soft reload", where we reload the changed files and construct and use a new Registry.</div>
<div tiddler="InvisibleInstrumentation" modifier="HowardLewisShip" modified="200610201803" created="200610201802" tags="">A feature of Tapestry 4 where the component id, type and parameters were "hidden" inside ordinary HTML tags.\n\nThis will show up inside Tapestry 5 pretty soon, and look something like:\n{{{\n<span t:type="If" t:test="prop:showWarning" class="warning"> \n . . .\n</span>\n}}}</div>
<div tiddler="LogicalPageName" modifier="HowardLewisShip" modified="200610081330" created="200610081330" tags="">A logical page name is the name of a page as it is represented in a URI.\n\nInternally, Tapestry operates on pages using full qualified class names. Technically, the FQCN is the class of the page's root element, but from an end developer point of view, the root element is the page.\n\nThe logical page name must be converted to a fully qualified class name.\n\nA set of LibraryMappings are used. Each library mapping is used to express a folder name, such as "core", with a Java package name, such as org.apache.tapestry.corelib. For pages, the page name is searched for in the pages sub-package (i.e., org.apache.tapestry.corelib.pages). Component libraries have unique folder names mapped to root packages that contain the pages (and components, and mixins) of that library.\n\nWhen there is no folder name, the page is expected to be part of the application,
under the pages sub-package of the application's root package.\n\nIf not found there, as a special case, the name is treated as if it were prefixed with "core/". This allows access to the core pages (and more importantly, components -- the search algorithm is the same).\n\nFinally, pages may be organized into folders. These folders become further sub-packages. Thus as page name of "admin/EditUsers" may be resolved to class org.example.myapp.pages.admin.EditUsers.\n\n</div>
<div tiddler="MainMenu" modifier="HowardLewisShip" modified="200609210701" created="200609210643" tags="">MasterIndex\n[[RSS feed|tap5devwiki.xml]]\n\n[[Tapestry 5 Home|http://tapestry.apache.org/tapestry5/]]\n[[Howard's Blog|http://howardlewisship.com/blog/]]\n\n[[Formatting Help|http://www.blogjones.com/TiddlyWikiTutorial.html#EasyToEdit%20Welcome%20NewFeatures%20WhereToFindHelp]]</div>
-<div tiddler="MasterIndex" modifier="HowardLewisShip" modified="200701051919" created="200609202214" tags="">Top level concepts within Tapestry 5.\n\nA //meta-note//: This is where new ideas are first explained, usually before being implemented. In many cases, the final implementation is\nnot a perfect match for the notes. That's OK ... as long as the official Maven documentation does a good job. It's not reasonable to expect developers to jump back in here and dot every i and cross every t if they're already expected to generate good Maven documentation.\n\n* PropBinding -- Notes on the workhorse "prop:" binding prefix\n* TypeCoercion -- How Tapestry 5 extensibly addresses type conversion\n* FormProcessing\n* DynamicPageState -- tracking changes to page state during the render\n* EnvironmentalServices -- how components cooperate during page render\n* ComponentMixins -- A new fundamental way to build web functionality\n* RequestTypes -- Requests, request processing
, URL formats\n* ComponentTemplates -- Issues about Component Templates\n* DeveloperProcedures -- Your a Tapestry committer ... how do you makes changes?\n* SmartDefaults -- do even more with event less\n* RandomIdeas -- stuff that doesn't fit elsewhere\n* ProblemsNeedingSolutions\n* ComponentDocumentation -- Generating Documentation about Components\n* TapestryLookAndFeel -- Default CSS\n* [[Assets]]\n* CaseInsensitivity -- case in URLs should not matter\n\n</div>
+<div tiddler="MasterIndex" modifier="HowardLewisShip" modified="200701161448" created="200609202214" tags="">Top level concepts within Tapestry 5.\n\nA //meta-note//: This is where new ideas are first explained, usually before being implemented. In many cases, the final implementation is\nnot a perfect match for the notes. That's OK ... as long as the official Maven documentation does a good job. It's not reasonable to expect developers to jump back in here and dot every i and cross every t if they're already expected to generate good Maven documentation.\n\n* PropBinding -- Notes on the workhorse "prop:" binding prefix\n* TypeCoercion -- How Tapestry 5 extensibly addresses type conversion\n* FormProcessing\n* DynamicPageState -- tracking changes to page state during the render\n* EnvironmentalServices -- how components cooperate during page render\n* ComponentMixins -- A new fundamental way to build web functionality\n* RequestTypes -- Requests, request processing
, URL formats\n* ComponentTemplates -- Issues about Component Templates\n* DeveloperProcedures -- Your a Tapestry committer ... how do you makes changes?\n* SmartDefaults -- do even more with event less\n* RandomIdeas -- stuff that doesn't fit elsewhere\n* ProblemsNeedingSolutions\n* ComponentDocumentation -- Generating Documentation about Components\n* TapestryLookAndFeel -- Default CSS\n* [[Assets]]\n* CaseInsensitivity -- case in URLs should not matter\n* FullReload -- Why limit reloading to just components?\n\n</div>
<div tiddler="OGNL" modifier="HowardLewisShip" modified="200610071249" created="200609202254" tags="">The [[Object Graph Navigation Library|http://ognl.org]] was an essential part of Tapestry 4.\n\nOGNL is both exceptionally powerful (especially the higher order things it can do, such as list selections and projections). However, for the highest\nend sites, it is also a performance problem, both because of its heavy use of reflection, and because it uses a lot of code inside synchronized blocks.\n\nIt will be optional in Tapestry 5. I believe it will not be part of the tapestry-core, but may be packaged as tapestry-ognl.\n\nThe "prop:" binding prefix is an effective replacement for OGNL in Tapestry 5. See PropBinding.\n</div>
<div tiddler="PageRenderRequest" modifier="HowardLewisShip" modified="200610081333" created="200610071313" tags="">Page render requests are requests used to render a specific page. //render// is the term meaning to compose the HTML response to be sent to the client. Note: HTML is used here only as the most common case, other markups are entirely possible.\n\nIn many cases, pages are stand-alone. No extra information in the URL is necesarry to render them. PersistentProperties of the page will factor in to the rendering of the page.\n\nIn specific cases, a page needs to render within a particular context. The most common example of this is a page that is used to present a specific instance of a database persistent entity. In such a case, the page must be combined with additional data, in the URL, to identify the specific entity to access and render.\n\n! URI Format\n\n{{{\n/page-name.html/id\n}}}\n\nHere "page-name" is the LogicalPageName for the page. \n\nThe &q
uot;.html" file extension is used as a delimiter between the page name portion of the URI, and the context portion of the URI. This is necessary because it is not possible (given the plethora of libraries and folders) to determine how many slashes will appear in the URI.\n\nThe context consists of one ore more ids (though a single id is the normal case). The id is used to identify the specific data to be displayed. Further, a page may require multiple ids, which will separated with slashes. Example: /admin/DisplayDetail.html/loginfailures/2006\n\nNote that these context values, the ids, are simply //strings//. Tapestry 4 had a mechanism, the DataSqueezer, that would encode the type of object with its value, as a single string, and convert it back. While seemingly desirable, this facility was easy to abuse, resulting in long and extremely ugly URIs.\n\nAny further information needed by Tapestry will be added to the URI as query parameters. This may include things like us
er locale, persistent page properties, applicaition flow identifiers, or anything else we come up with.\n\n! Request Processing\n\nOnce the page and id parameters are identified, the corresponding page will be loaded.\n\nTapestry will fire two events before rendering the page.\n\nThe first event is of type "setupPageRender". This allows the page to process the context (the set of ids). This typically involves reading objects from an external persistent store (a database)\nand storing those objects into transient page properties, in expectaion of the render.\n\nThe @SetupPageRender annotation marks a method to be invoked when this event is triggered. The method may take one or more strings, or an array of strings, as parameters; these will be\nthe context values. The method will normally return void. Other values are ''TBD''. It may also take other simple types, which will be coerced from the string values.\n\n{{{\n@SetupPageRender\nvoid setup(long id)\n{\n . .
.\n}\n}}}\n\n\n\nThe second event is of type "pageValidate". It allows the page to decide whether the page is valid for rendering at this time. This most often involves a check to see if the user is logged into the application, and has the necessary privileges to display the contents of the page. User identity and privileges are //not// concepts built into Tapestry, but are fundamental to the majority of Tapestry applications.</div>
<div tiddler="ProblemsNeedingSolutions" modifier="HowardLewisShip" modified="200701032351" created="200611230401" tags="">There are a few things that I'm concerned about.\n\n!Render Complexity\n\nAll those states in the render component state machine may be a little much, especially ~PreBeginRender, ~BeginRender and ~PostBeginRender. In addition, it doesn't work for a case I'm interested in ... for link components, I'd like to use the RenderInformals mixin, but also support a disable parameter that turns off the <a> tag (but still renders the body). The state machine currently is set up so that returning false in any of the ~BeginRender states skips all the way to ~AfterRender, bypassing the template and/or body.\n\nStill don't have a perfect solution for the above (it may not be solvable via mixins, which may show limitations in the component/mixin model). I have added a @MixinAfter annotation which simplifies the state machine somewhat.</div>
Modified: tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.xml
URL: http://svn.apache.org/viewvc/tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.xml?view=diff&rev=496924&r1=496923&r2=496924
==============================================================================
--- tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.xml (original)
+++ tapestry/tapestry5/tapestry-project/trunk/src/site/resources/tap5devwiki.xml Tue Jan 16 19:38:16 2007
@@ -6,27 +6,33 @@
<description>The quick and dirty one-stop shopping of random ideas for Tapestry 5.</description>
<language>en-us</language>
<copyright>Copyright 2007 HowardLewisShip</copyright>
-<pubDate>Fri, 05 Jan 2007 19:35:21 GMT</pubDate>
-<lastBuildDate>Fri, 05 Jan 2007 19:35:21 GMT</lastBuildDate>
+<pubDate>Tue, 16 Jan 2007 14:51:05 GMT</pubDate>
+<lastBuildDate>Tue, 16 Jan 2007 14:51:05 GMT</lastBuildDate>
<docs>http://blogs.law.harvard.edu/tech/rss</docs>
<generator>TiddlyWiki 2.0.11</generator>
<item>
-<title>CaseInsensitivity</title>
-<description>One aspect of "pretty" URLs for Tapestry pages is that case should not matter. The user should be able to manually type a URL without respect to case, and have it //just work//. Turns out that's hard on a number of fronts.<br /><br />! Page Names<br /><br />In Tapestry 4 and in the current Tapestry 5 code base, that is a problem. Tapestry starts with a page name, and uses that to hunt around and locate the page class and from there, the page template, etc.<br /><br />That hunting around tends to be problematic, because ClassLoader.getResource() is case //specific//. In addition, ClassLoader doesn't directly provide any way to introspect the available classes.<br /><br />You'd think that you could, as a page is first accesssed, record its name in a case insensitve cache somewhere. However, that doesn't work. First, in a cluster, the server handling the request may simply never have handled a request
for that page before, so it won't have an up-to date cache. Likewise, after a server restart, existing requests (possibly cached in a browser's bookmarks) <br /><br />However, I've been doing some research. ClassLoader.getResources() , passed a folder name (such as "org/example/myapp/pages/") will yield one or more URLs for the folders. Some of these will be URLs for file systems, some will be URLs for JARs. You can differentiate by the value returned from URL.openConnection().<br /><br />For file system URLs, opening the stream provides a list of the files and folders for that package. Using this, we can identify the protential classes, and identify sub-folders/sub-packages to recursively scan.<br /><br />For JAR URLs, we can cast to JARURLConnection and obtain the JarFile instance for the entire JAR. From there we can obtain a list of entries.<br /><br />Combining these two approaches should allow us, at appli
cation startup, to locate all page instances. We'll be able to build a case-insensitive mapping from logical page name to Java class name.<br /><br />! Component Ids<br /><br />Component ids and id paths show up in some URLs (primarily action URLs, but even so). As currently implemented, ids are case sensitive. With some work, it should be possible to make accessing a component by its id, or id path, case insensitive. This should include errors if two components have the same case-insensitive id.<br /><br />! Query Parameters<br /><br />Not sure this is as relevant, because the types of URLs that matter will usually not include any query parameters. In terms of form submissions ... well, the entire client side is wired case sensitivly, so making form submissions case inensitive seems like a useless exercise.</description>
-<link>http://tapestry.apache.org/tapestry5/tap5devwiki.html#CaseInsensitivity</link>
-<pubDate>Fri, 05 Jan 2007 19:34:38 GMT</pubDate>
+<title>FullReload</title>
+<description>It has occured to me that by adding yet another smart class loader, we could possibly set up a system where we track date time modified on all the modules, service interfaces, and implementation files loaded by the Registry, such that changes to any of the files could result in a kind of "soft reload", where we reload the changed files and construct and use a new Registry.</description>
+<link>http://tapestry.apache.org/tapestry5/tap5devwiki.html#FullReload</link>
+<pubDate>Tue, 16 Jan 2007 14:50:26 GMT</pubDate>
</item>
<item>
<title>MasterIndex</title>
-<description>Top level concepts within Tapestry 5.<br /><br />A //meta-note//: This is where new ideas are first explained, usually before being implemented. In many cases, the final implementation is<br />not a perfect match for the notes. That's OK ... as long as the official Maven documentation does a good job. It's not reasonable to expect developers to jump back in here and dot every i and cross every t if they're already expected to generate good Maven documentation.<br /><br />* PropBinding -- Notes on the workhorse "prop:" binding prefix<br />* TypeCoercion -- How Tapestry 5 extensibly addresses type conversion<br />* FormProcessing<br />* DynamicPageState -- tracking changes to page state during the render<br />* EnvironmentalServices -- how components cooperate during page render<br />* ComponentMixins -- A new fundamental way to build web functionality<br />* RequestTypes -- Requests, requ
est processing, URL formats<br />* ComponentTemplates -- Issues about Component Templates<br />* DeveloperProcedures -- Your a Tapestry committer ... how do you makes changes?<br />* SmartDefaults -- do even more with event less<br />* RandomIdeas -- stuff that doesn't fit elsewhere<br />* ProblemsNeedingSolutions<br />* ComponentDocumentation -- Generating Documentation about Components<br />* TapestryLookAndFeel -- Default CSS<br />* [[Assets]]<br />* CaseInsensitivity -- case in URLs should not matter<br /><br /></description>
+<description>Top level concepts within Tapestry 5.<br /><br />A //meta-note//: This is where new ideas are first explained, usually before being implemented. In many cases, the final implementation is<br />not a perfect match for the notes. That's OK ... as long as the official Maven documentation does a good job. It's not reasonable to expect developers to jump back in here and dot every i and cross every t if they're already expected to generate good Maven documentation.<br /><br />* PropBinding -- Notes on the workhorse "prop:" binding prefix<br />* TypeCoercion -- How Tapestry 5 extensibly addresses type conversion<br />* FormProcessing<br />* DynamicPageState -- tracking changes to page state during the render<br />* EnvironmentalServices -- how components cooperate during page render<br />* ComponentMixins -- A new fundamental way to build web functionality<br />* RequestTypes -- Requests, requ
est processing, URL formats<br />* ComponentTemplates -- Issues about Component Templates<br />* DeveloperProcedures -- Your a Tapestry committer ... how do you makes changes?<br />* SmartDefaults -- do even more with event less<br />* RandomIdeas -- stuff that doesn't fit elsewhere<br />* ProblemsNeedingSolutions<br />* ComponentDocumentation -- Generating Documentation about Components<br />* TapestryLookAndFeel -- Default CSS<br />* [[Assets]]<br />* CaseInsensitivity -- case in URLs should not matter<br />* FullReload -- Why limit reloading to just components?<br /><br /></description>
<link>http://tapestry.apache.org/tapestry5/tap5devwiki.html#MasterIndex</link>
-<pubDate>Fri, 05 Jan 2007 19:19:59 GMT</pubDate>
+<pubDate>Tue, 16 Jan 2007 14:48:59 GMT</pubDate>
+</item>
+<item>
+<title>CaseInsensitivity</title>
+<description>One aspect of "pretty" URLs for Tapestry pages is that case should not matter. The user should be able to manually type a URL without respect to case, and have it //just work//. Turns out that's hard on a number of fronts.<br /><br />! Page Names<br /><br />In Tapestry 4 and in the current Tapestry 5 code base, that is a problem. Tapestry starts with a page name, and uses that to hunt around and locate the page class and from there, the page template, etc.<br /><br />That hunting around tends to be problematic, because ClassLoader.getResource() is case //specific//. In addition, ClassLoader doesn't directly provide any way to introspect the available classes.<br /><br />You'd think that you could, as a page is first accesssed, record its name in a case insensitve cache somewhere. However, that doesn't work. First, in a cluster, the server handling the request may simply never have handled a request
for that page before, so it won't have an up-to date cache. Likewise, after a server restart, existing requests (possibly cached in a browser's bookmarks) <br /><br />However, I've been doing some research. ClassLoader.getResources() , passed a folder name (such as "org/example/myapp/pages/") will yield one or more URLs for the folders. Some of these will be URLs for file systems, some will be URLs for JARs. You can differentiate by the value returned from URL.openConnection().<br /><br />For file system URLs, opening the stream provides a list of the files and folders for that package. Using this, we can identify the protential classes, and identify sub-folders/sub-packages to recursively scan.<br /><br />For JAR URLs, we can cast to JARURLConnection and obtain the JarFile instance for the entire JAR. From there we can obtain a list of entries.<br /><br />Combining these two approaches should allow us, at appli
cation startup, to locate all page instances. We'll be able to build a case-insensitive mapping from logical page name to Java class name.<br /><br />! Component Ids<br /><br />Component ids and id paths show up in some URLs (primarily action URLs, but even so). As currently implemented, ids are case sensitive. With some work, it should be possible to make accessing a component by its id, or id path, case insensitive. This should include errors if two components have the same case-insensitive id.<br /><br />! Query Parameters<br /><br />Not sure this is as relevant, because the types of URLs that matter will usually not include any query parameters. In terms of form submissions ... well, the entire client side is wired case sensitivly, so making form submissions case inensitive seems like a useless exercise.</description>
+<link>http://tapestry.apache.org/tapestry5/tap5devwiki.html#CaseInsensitivity</link>
+<pubDate>Fri, 05 Jan 2007 19:34:00 GMT</pubDate>
</item>
<item>
<title>ComponentTemplates</title>
<description>There are some issues related to component templates.<br /><br />Firstly, people are really interested in seeing the return of InvisibleInstrumentation. =That is coming.= That is now available.<br /><br />Secondly, the idea that templates are well-formed XML documents is causing some issues.<br /><br />The problem is related to entities and doctypes.<br /><br />Unless you provide a doctype for the template, [[entities|http://www.htmlhelp.com/reference/html40/entities/]] don't work; they result in template parse errors.<br /><br />If you provide a standard doctype, say<br />{{{<br /> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"<br /> "http://www.w3.org/TR/REC-html40/loose.dtd"><br />}}}<br /><br />You also get parse errors, because the DTD does some odd things with comments that the Java SAX parser doesn't seem to
understand.<br /><br />I've had better luck with the XHTML doctype:<br />{{{<br /><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"<br />"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><br />}}}<br /><br />But this doesn't render quite the way I want it to.<br /><br />Further, entities in the text are converted to unicode by the parser, then converted to //numeric// entities on output. Not quite WYSIWYG and potentially confusing.<br /><br />It may be necessary to discard SAX and build a limited XML parser that allows entities to be passed through unchanged (they would become a special type of document token).<br /><br />Lastly, the question is how to get the correct DOCTYPE into the rendered output, espcially in the common case that a Border component provides the outer tags, as is common in Tapestry 4. This may have to be configured as a ann
otation on page classes.<br /><br />! Template Location<br /><br />Concensus is building that templates should //not// have a {{{.html}}} extension, but something specific to Tapestry, perhaps {{{.tap}}} or {{{.tsp}}}.<br /><br /><br />Further, there are invalid, but present, security concerns that the templates should live on the classpath or in WEB-INF, but not in the root folder. Both of these issues would simplify things for Tapestry.<br /></description>
<link>http://tapestry.apache.org/tapestry5/tap5devwiki.html#ComponentTemplates</link>
-<pubDate>Fri, 05 Jan 2007 19:19:01 GMT</pubDate>
+<pubDate>Fri, 05 Jan 2007 19:19:00 GMT</pubDate>
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<title>SmartDefaults</title>
@@ -128,12 +134,6 @@
<category>events</category>
<link>http://tapestry.apache.org/tapestry5/tap5devwiki.html#ComponentEvent</link>
<pubDate>Sun, 08 Oct 2006 13:59:00 GMT</pubDate>
-</item>
-<item>
-<title>ComponentActionRequest</title>
-<description>Component actions are actions that reflect user interaction with a component within a page. Again, this falls into several broad categories:<br /><br />* Links that perform a server-side action, and result in a page refresh, or a new page being displayed.<br />* Ajax style links, which perform a server-side action, and refresh only part of the page.<br />* Forms which perform a server-side action, followed by a page refresh (or new page being displayed).<br />* Ajax style forms, which trigger an action, followed by a refresh of part of the page.<br />* Other user interactions, which result in a server side action, and a partial page refresh.<br /><br />In all of these cases, one or more ComponentEvents is fired. The result of ComponentEvent determines whether a partial page render or a full page render occurs.<br /><br />In the later case, a client side redirect is sent, to force the browser to initial
a new PageRenderRequest. This addresses an issue in Tapestry 4, in that following a link or form submission, the URL would indicate details about the previous page, not the newly displayed page, and clicking the browser refresh button could cause a server side operation to occur again (which would often be quite undersirable).<br /><br />!URI Format<br /><br />{{{<br />/page-name.event-type/component-id-path/id<br />}}}<br /><br />Here page-name is the LogicalPageName. The event-type is a string that identifies the type of event (and will ultimately be used to select an event handler method). <br /><br />The component-id-path is a dot-separated series of component ids, used to identify a specific component within the overall page.<br /><br />The id is optional, and may be repeated. The id value or values will be provided to the event handler method.<br /><br />Example: /Login.submit/form
(the URI for a form component on page Login).<br /><br />Example: /admin/UserProfile/action/menu.delete/37 (component menu.delete of the UserProfile page, with an id of 37).<br /></description>
-<link>http://tapestry.apache.org/tapestry5/tap5devwiki.html#ComponentActionRequest</link>
-<pubDate>Sun, 08 Oct 2006 13:35:00 GMT</pubDate>
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