Regarding sorting properties: The spec implies that sorting properties is not required. The only thing that matters is that the bytes for the values are in the same order as the traits property list.
https://www.adobe.com/content/dam/acom/en/devnet/pdf/amf-file-format-spec.pdf HTH, -Alex On 11/20/18, 11:31 AM, "Greg Dove" <greg.d...@gmail.com> wrote: On Wed, Nov 21, 2018 at 7:52 AM Alex Harui <aha...@adobe.com.invalid> wrote: > In snooping around the code a bit, I noticed: > > 1) Flex MX ArrayCollections usually wraps an ArrayList and thus actually > justs reads/writes an Array. So, in theory, the bytes that you find when > serializing an Array vs ArrayCollection should only differ by the alias > stored (and maybe traits). > > Yes, that's what I meant when I said that in terms of 'externalizable' it seems quite 'easy'. I'm actually mapping the alias to royale ArrayList and have this working in a special case setup for now on the inbound side. My intention is to make something general that is 'Externalizable' for royale though. > 2) AMFBinaryData has some special casing for ArrayCollection already, and > probably shouldn't. IMO, that special handling was probably to allow > reading of an AC and ending up with an Array. We don't want that in Royale. > > It doesn't really do anything as it was. It just arrives as Array (which was usable, but not ideal) - this side seems easier to fix. But it doesn't handle sending yet, that's the main focus for me right now. > 3) AMFBInaryData implies that there is an externalizable bit in the byte > stream. However, it is not set to true in writeTraits and probably should > be, and further, the property list should probably not be written to the > stream if the class is IExternalizable. The API for IExternalizable > implies that the implementation "knows" the order of properties. > > Yes I have no properties for the AC output - if Externalizable, the properties are ignored but I will double check I am setting the externalizable marker bit correctly- thanks > One other thought (you've may have already realized this): You may not > need RemoteObject and a server to test IExternalizable. You could write > a Flash SWF that writes to ByteArray and then dumps the actual bytes and > compare to a JS version using AMFBinaryData. I think the bytes should be > exactly the same. > Yes, I did something like this already, although it was with a variation of AMFBinaryData that works in swf instead of javascript, and not with exactly the same complex content yet, so far just testing combinations of ArrayCollections, including reference copies.... I may go back to that, but I thought I would start again by round-tripping something that decodes well already in the javascript version, because I am planning to use sort() on the properties for reading and writing , which should theoretically make the virtual object tables the same for reader and writer - this is the part that becomes hard to compare between the implementations with complex graphs, because the indexing order for object references will change depending on the order that they are encountered when writing (properties order) as they are recursed - and so makes 'actual bytes' comparisons not easy between different implementations. (Hopefully that makes sense) btw The avmplus code has been at least helpful already to catch another thing that is missing in the code we have :) if a function is assigned as a value to a property (variable or accessor with Function type ) then that value needs to be written as undefined > HTH, > -Alex > > On 11/20/18, 10:14 AM, "Greg Dove" <greg.d...@gmail.com> wrote: > > Thanks guys, > > I appreciate any guidance. I will take a look at the avmplus code. > BlazeDS > has a bunch of code that special-cases collection handling so I was > looking > for something that might be closer to how the player does it. But if I > need > to I will go back there. > > All AC does is say 'I'm external' and then outputs the internal source > array. So it seems 'easy' but I think the object tracking is providing > wrong indexing for subsequent readers. > > So far (and I guess the caveat there is that I have not been receiving > really complex objects) the reading side seems fine, it is the writing > where I getting bad results. I need to make sure the 'virtual' > reference > tables that the future reader uses have correct index references. > Anyway, I do have some semi-complex content (a user object with roles > and > other related subobjects) deserializing correctly with AC being > referenced > correctly in the final deserialized object, and it has some internal > object > references, so I will start by trying to round-trip that through > serialization/deserialization in local AMFBinaryData and look for more > clues. But I will alos check the avmplus code first - thanks! > > Cheers, > Greg > > > > On Wed, Nov 21, 2018 at 5:56 AM Alex Harui <aha...@adobe.com.invalid> > wrote: > > > This is a major US holiday week, so not a good week for trying to get > > internal documents released. So looking at the code in AVMPlus is > probably > > as good as it will get. > > > > I could be wrong, but I would think IExternalizable would not affect > the > > byte stream very much at all. I would think its only impact would > be to > > pass the bytes to the implementing class. The goal, AIUI, isn't to > encode > > an ArrayCollection into the bytes, it is to take a subset of the AC > > properties and put them in the stream so that the deserialization > code in > > BlazeDS and AMFPHP can decode it into whatever class represents AC > on the > > server. So not only do you have AVMPlus code to reference, I think > there > > may be code in BlazeDS. > > > > I would think the basic AMF deserialization logic currently is: > > > > ReadAlias (of the first class in the stream) > > GetClassFromAlias > > New Class > > Read property list of class. > > readAlias (the type of the first property in the property list > > GetClassFromAlias > > New Class (to get an object that is the value of that first property) > > Recursively deserialize that object > > Set the first property to that object > > Loop. > > > > IMO, IExternalizable is only supposed to break out of this pattern > and > > call the implementation to recursively deserialize the object. > > > > I think the code just needs to add a check after getClassFromAlias > that > > determines if the instance is IExternalizable and then skips getting > the > > property list and just calls readExternal. > > > > Of course, I could be wrong... > > -Alex > > > > > > > > On 11/20/18, 3:48 AM, "Frost, Andrew" <andrew.fr...@harman.com> > wrote: > > > > Hi guys > > > > I'm not 100% sure whether this will help, but if I'm right in > thinking > > that what you're trying to do is to mimic the Flash object > serialisation, > > then I think that this information is actually in the public domain > > already.. > > > > Carlos, you wrote: > > "ArrayCollection uses IExternalizable and that part is our main > > problem since we don’t have references, just simple docs but no real > > implementation, guides or notes about it." > > > > The IExternalizable.as implementation is part of avmplus: > > > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fadobe%2Favmplus%2Fblob%2Fmaster%2Fcore%2FIExternalizable.as&data=02%7C01%7Caharui%40adobe.com%7C7d3956dfaae248e5f25008d64f1ec082%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C636783390831794611&sdata=KsvrBlOz%2FTAzgcYH6%2B7wG%2BGFosvabPjvn3qi59PkwtE%3D&reserved=0 > > ArrayCollection is of course part of Flex: > > > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fapache%2Fflex-sdk%2Fblob%2Fmaster%2Fframeworks%2Fprojects%2Fframework%2Fsrc%2Fmx%2Fcollections%2FArrayCollection.as&data=02%7C01%7Caharui%40adobe.com%7C7d3956dfaae248e5f25008d64f1ec082%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C636783390831804621&sdata=pvspkTd0zb8Lo0KPeLwJDUM6ggnvHwR7sgcymNjyt%2F8%3D&reserved=0 > > and you can then follow through what's happening. > > > > And, having just done that, I'm guessing you're looking at how > > "readObject" works. Presumably you're serialising into a ByteArray, > which > > means ultimately you'll end up in the heart of the avmplus code: > > > > > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fadobe%2Favmplus%2Fblob%2Fmaster%2Fcore%2FToplevel.cpp%23L1504&data=02%7C01%7Caharui%40adobe.com%7C7d3956dfaae248e5f25008d64f1ec082%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C636783390831804621&sdata=iYXa9AMHUo2jqnw3hJVx0Dx%2BQvf%2ByEvmjn2pY4eeVaQ%3D&reserved=0 > > and > > > > > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fadobe%2Favmplus%2Fblob%2Fmaster%2Fcore%2FAvmSerializer.cpp&data=02%7C01%7Caharui%40adobe.com%7C7d3956dfaae248e5f25008d64f1ec082%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C636783390831804621&sdata=gaarXejHyDWsPIDAj3KkQwSWyZR0Acd6rFk1eyw%2F16g%3D&reserved=0 > > which is quite complex...! > > > > Not sure if those help at all but it looks to me like it should > be > > possible to have some JavaScript code to do all this. If this is the > sort > > of area that you're looking at then let me know, I've got extensive > > experience with the avmplus code and have builds of it that I can > > tweak/play with to debug what happens in various scenarios! but I > don't > > have any experience with using RemoteObject hence this may all be > > completely irrelevant.. > > > > thanks > > > > Andrew > > > > > > -----Original Message----- > > From: Greg Dove [mailto:greg.d...@gmail.com] > > Sent: 20 November 2018 09:47 > > To: dev@royale.apache.org > > Subject: [EXTERNAL] Re: Problems sending MX ArrayCollections > with MX > > RemoteObject > > > > Hi Alex, > > > > To follow on from what Carlos explained... your initial > > implementation with AMFBinaryData was working quite well for smaller > object > > graphs. > > > > And I was able to make some changes to get it to special-case > > ArrayCollection for now on the reading side (it's not a proper > > implementation, but it was to get things working for now). > > > > What I am missing is some good implementation notes ('conforming > > readers and writers must do this'). For example, I'm not sure what > the > > object table > > (rememberObject/traitsByReference) rules are for > Externalizables, and > > it's really hard to 'discover' through comparisons with things like > > ByteArray or BlazeDS responses partly because the undefined output > order of > > the fields in a large graph which makes direct comparison of byte > sequences > > from the 2 sources not so easy. > > > > In the end I will be happy to keep working on getting > AMFBinaryData > > fully featured in my own time to help with the general MX effort, but > > Carlos needs certain things working for his project, which are our > current > > priorities. > > > > I do have some improvements that I can get in for AMFBinaryData > in the > > next few days (I'm still refining things): > > I have some code that avoids inappropriate field data for > > serialization: > > only accessors with readwrite access (not getter only or setter > only) > > no static accessors or variables excludes any field with 'Transient' > > metadata > > > > > > But I'm still actively trying to figure out how to get the AC > writing > > correctly in a complex graph, and I really need to understand what > the > > rules are supposed to be. In terms of 'Externalizable' AC seems quite > > simple, so I thought it would be easy... but I think I am messing up > the > > object reference table when I do this... I was hoping there might be > > something documented for implentation notes that is 'public' but > 'not well > > publicized' that you might be aware of, perhaps through some of your > > internal connections. if we can get this fully fledged as quickly as > > possible, even if it just focused on AC for now on the > 'Externalizable' > > side then that will help Alina and others as well, I think. I've > had > > my head in this for a bit now, so if I have the info, I will find > the time. > > > > Hopefully you can provide some insight! > > -Greg > > > > > > > > > > On Tue, Nov 20, 2018 at 10:19 PM Carlos Rovira < > > carlosrov...@apache.org> > > wrote: > > > > > Hi Alex, > > > > > > Greg and I are working this days in sending MX ArrayCollection > with > > MX > > > RemoteObject to BlazeDS. We found that part is not working. > > > This is huge problem since without solving this we can't > progress in > > > our migration, so hope you could take care of this issue and > help us > > > to find the solution. > > > > > > The main problem is that we don't have or find a good > reference of > > the > > > way it should be implemented and the format makes it difficult > to > > discover. > > > ArrayCollection uses IExternalizable and that part is our main > > problem > > > since we don’t have references, just simple docs but no real > > > implementation, guides or notes about it. > > > > > > Our better bet is that you could get some help at Adobe > internally > > > since I don't think this info is in internet (at least we > search > > > heavily to try to find). > > > > > > I think with out this problem fixed no application using MX > > > RemoteObject for communication could be migrated from Flex to > > Royale, > > > since as soon they want to send and complex graph that uses MX > > ArrayCollection it will fail. > > > > > > Greg can comment more about this problem since he was working > hard > > on > > > the issue this days. > > > > > > Thanks in advance for your help > > > > > > > > > -- > > > Carlos Rovira > > > > > > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fclicktime.symantec.com%2Fa%2F1%2FfECozPwEKwcw-Ikf3a3HC4wIeBurGWwaEzA&data=02%7C01%7Caharui%40adobe.com%7C7d3956dfaae248e5f25008d64f1ec082%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C636783390831804621&sdata=u%2Ft85LFe47ahBNfiL1v4nD%2B%2BHb3v%2BbEwcLLdfidZgu8%3D&reserved=0 > > > > > > E2QRfLRk=?d=ezg34mnblPal5Fyvz8kFGVPZYWSwgwTIshTP4R6ZZBwOU_9DnOO0vulBQk > > > > > > WMjrartx1QiEcmaQF0W-s21xYUmmwd8VZI2paWYczV2yv9_RGOX7HvcYTbT5-boGyLZsXs > > > > > > i81oDbXjP_kE8HOHv-CO0RmzekCJ4IXZ1dfI4iczGVVKJlFs3Z9QfZKPIsqL8bfsOPw83b > > > > > > 72ng2yLuRO4g252wF9TWPtu2CAYr-VXOzqqiXrKi2Zrk9wM3FFEc9hUJ9dpb5b4bflw_r8 > > > > > > nj8z30JVYIfUlmah923Rr-8mDPJO0JvmMDiSEWJojxBQAi_wWktydSWyDvGSDJidxjtFsq > > > > > > UpjRFuCNjuBFxim5GH2bZCj-0Gra3yfagBCVNYiT95Zq5loJN_-kHI8W8-jEOaVK-3Hgd4 > > > > > > iAgxK7oB4xr5-PopRVTJDHsb3OeOqtd9_rjFDbCq0EtWEowCy2xcWbcBzo0IiQhRTv3Mrs > > > x48H3qjmo%3D&u=http%3A%2F%2Fabout.me%2Fcarlosrovira > > > > > > > > > > > >
