I'm creating a bussines process diagram in Enterprise Architect 8, using BPMN.
How to connect Data Object with Message Flow by association?
I can't link association to message flow.
Not exactly sure what the question is, but one tip will be, try to use the toolbox connectors (instead of quicklinker) in such situations.
I've put up a quick mock up of connecting two data objects, a) with dataassociation, b) with messageflow, also shown example connecting data object and message with a) dataassociation b)messageflow.
I can't comment if these are syntactically correct, but can do it using the toolbox
Related
I just discovered Axon framework and am very eager to use it as it answers a lot of my questions and concerns about DDD.
The first project I'd like to use it on contains small cameras which are controlled via the GigEVision protocol (over TCP and UDP for the control and stream channels). I think my problem would be the same for any case where we maintain a connection to an external component or more generally we want to link an external component lifecycle to Axon's lifecycles.
I'd like to have an Aggregate named Camera to which I can send Commands to grab 1 image or start grabbing N images at a certain FPS.
What I'm not sure about is how to manage the connection to an external component in my Aggregate.
- Should I inject the client to my camera in my Camera Aggregate and consider connecting to it as part of my protocol / business commands? In this case how would I link the camera lifecycle (a camera get disconnected all of a sudden) to the aggregate lifecyle (create a corresponding CameraDisconnectedEvent)?
- Should the connection be handled in a side car Saga which get the camera client injected, the saga starting on ConnectionRequestedEvent and stopping as soon as we get a connection error from the camera. I would get the same issue of linking the connection lifecycle to the lifecycle of the Saga I think.
- Am I leaking implementation details in the business layer and should manage the issue an other way?
- Am I just using the wrong tool for this job and should not try to force it into Axon?
Thank you very much in advance, hope my message and issues make sense.
Best regards,
First and foremost what you should do, is ensure the language spoken by the GigEVision protocol by no means transitions over into your other domain.
These two should be separate and remain so, as they cover different concerns.
This brings to light the necessity to have a translation layer of some sort.
More formuly called a context mapping. From a DDD perspective, you would take this even further by talking about an Anti-Corruption Layer.
The name already says it, you add a layer to ensure you are not corrupting your domain logic with that from another domain.
Another useful topic to read up on here would be the notion of a Bounded Context.
I digress though, let's go back to the problem at hand: where to position this anti-corruption layer.
What is currently unclear to me, is what domain requirements are in place why the connection is required to be maintained all the time when requesting for images.
Is the command you want to send requesting for a live feed? Or just "some" images from a given time frame?
In both scenarios I am not immediately convinced that any of these operations requires the validation through a single Camera aggregate to be honest.
You could still model this in a command and event format, as the messaging paradigm is very helpful to allow clean segregation of concerns.
But given the current description, I am uncertain whether you need DDD's idea of an Aggregate to model a single Aggregate in.
I might be wrong on this note, but I just don't know enough about your domain at this stage.
That's my two cents to the situation, hoping this helps!
I am finding a solution to handle dynamic data / list to all nodes or specified nodes at the time creating a contract in Corda. I don’t think Oracle is a good approach to use in my case for the following reasons:
The data can be a list of for example legal entity names, they are not from outside world, not a single value;
The list is depended on particular field(s) selected, therefore will need perhaps a centralized place to maintain the data relationship;
Appreciate if anyone can help on this. Thanks.
Kwan
This question is a little difficult to answer without further details on your use-case. However, on the surface, an Oracle doesn't sound like a bad solution:
The data provided by an oracle can be a list
The term "outside world" simply refers to any information not included in the transaction itself. This term should not be taken too literally.
Ultimately, you can think of an Oracle as a provider of "official" data. You request a command including the data from the oracle, include it in the transaction, and the oracle will sign over the transaction if and only if it agrees that the data in the command is true. As long as the Oracle is trusted by all parties involved, this allows data from outside the transaction to be included in the transaction in a reliable way.
I've been experimenting with Titan over the past few weeks and would like some pointers on the way forward, plus a few specific questions. The purpose of the project is to store log data on a Cassandra cluster (for this question let's use the example of web traffic) and represent relationships in a Titan graph. All nodes are modelled as having an entity value and type (e.g. "google.com","hostname"), and edges have a label (e.g. "connects") as well as several attributes of the relationship (timestamp, flow length and so on).
Once this data is stored in cassandra and represented as a Titan graph, I plan to use d3 code to generate visualisations. At the end of the tunnel I am hoping to be able to build large-scale, interactive, complex graph networks that look something like this: http://goo.gl/CVEd55
My current setup is as follows:
A python script to convert log files into vertices.csv and edges.csv files for Gremlin to load in
Titan Server 0.4 (using CassandraThrift as the storage backend) - gremlin script to load converted data into Titan
Python script that uses NetworkX to open a RexPro connection, allowing the analyst to enter a custom Gremlin query, outputting the result as a JSON
Local web front-end that uses the generated JSON and d3 to display the results of the query as a graph
Ideally as a test base case, I would like the user to be able to type a Gremlin query into the web front-end and be directed to a page containing an interactive d3 graph of the result.
My specific questions are are follows:
What is the process for assigning attributes to edges? I have had trouble finding sample code that helps me represent the graph using the model listed above.
My gremlin script to load data into Titan uses bg.commit() to create a batch graph which is later referenced in the RexPro connection conn= RexProConnection('localhost,8184,'bg'). This was working originally but after changing my load script, clearing the graph in Gremlin and then reloading, the RexPro connection cannot be opened due to the graph bg apparently not existing. What is the process of updating graphs in Titan? Presumably running a load script twice using the same graph will only add nodes/vertices to the existing one, so how would I go about generating a new graph with the same name every time I update my model, and have RexPro be able to reference it when running a query?
How easy would it be to extend the interface to allow an analyst to enter SQL queries into the front end, using RexPro to access the graph in a similar way to the one described?
Apologies for the long post, but if anyone could share their expertise that would be much appreciated!
For d3 visualization, you can use force directed graph. There are a few variations of them.
Relationship Graph
https://vida.io/documents/qZ5SJdRJfj3XmSXYJ
Force Layout Tree
https://vida.io/documents/sy7vzWW7BJEvKdZeL
If your network contains a large number of node and edges, you'll need to cluster data before visualizing. You can use tools like Gephi, NodeXL to perform clustering. Then use clustered data to build force directed visualization.
What is the process for assigning attributes to edges?
The process is the same as adding properties to vertices. Get an Edge instance then do:
Edge e = g.addEdge(v1,v2,'label')
e.setProperty('weight',0.1d)
As for:
What is the process of updating graphs in Titan? Presumably running a load script twice using the same graph will only add nodes/vertices to the existing one, so how would I go about generating a new graph with the same name every time I update my model, and have RexPro be able to reference it when running a query?
You don't want a reference to a BatchGraph after loading as it comes with limitations that will prevent you from querying. It sounds like you should just configure "yourgraph" in rexster.xml, when you load through your script, simply wrap your rexster.xml configured Graph in your code, and perform your load operations against it. When you want to query it, simply reference "yourgraph" instead of "bg".
conn = RexProConnection('localhost,8184,'yourgraph')
How easy would it be to extend the interface to allow an analyst to enter SQL queries into the front end, using RexPro to access the graph in a similar way to the one described?
It's hard to say if that's "easy" as that depends on factors outside of just the technology. I'll say that it's possible to to build an interface that accepts Gremlin queries (your wrote SQL, but I assume you meant Gremlin), passes them to Rexster and gets back an answer. What you do with that answer is up to you, but as far as Rexster's part plays into it, I don't see why that would be a problem.
I have an orchestration which is receiving messages from the message box of type XmlDocument. The messages have promoted properties and I am including the property schema in my project so that I may filter on them (a separate application is creating these messages). I am then assigning the untyped message to a typed message (I am not altering the name space) via a standard message assignment shape e.g.
MsgAgressoNewStarters = MsgXmldoc;
I am then outputting the message to a file location. However when I do this the property schema is also outputted.
How can I prevent this? I have tried filters etc.
Thanks
10th May 2012
I think I am possibly going about this the wrong way perhaps if I describe the full scenario you may be able to spot my deliberate mistake ;)
We are using BizTalk 2010.
I have a BizTalk application which talks to a 3rd party generic webservice that returns reports from one of our systems. This application is activated via the scheduled adapter which sends an XML document containing two values, the report name and the interface it is for. The web service returns the report as a string on a single XML node, this string in its self is an XML document. I then load this string into a message of type System.Xml.XmlDocument. There is no way of telling from the format of the data what report or for what interface this message is for. I need to send this message to the messagebox for it to be picked up by any number of related biztalk applications. So far I have tried creating a correlation set with the two values (from a property schema) & used that as the initialising correlation set on the send shape. I have then used the same property schema on another BT application to filter the message. This works but for some reason I get two messages, one being the XML which activities the orchestration which has the same fields as the property schema & correlation set. BizTalk doesn't seem to be able to tell the difference between them although they are structurally different and this is where my problem starts.
I am now thinking of creating a multipart message in the report application one part being the XmlDocument and the other being a header with the values I wish to route on.
Hope that makes some kind of sense.
I've actually now answered my own question, because both messages have the same properties I am inadvertently subscribing to both, d'oh!
I have a asp.net web application that uses Entity Framework. The application data layer uses a method outlined by Jordan Van Gogh found here. In a nutshell, this method uses one shared objectcontext instance per http request and is disposed of using a AspNetObjectContextDisposalModule that inherits IHttpModule.
I have added another project, a few additional tables, and setup a data layer that copies (exactly) the example I described above to my application. This additional project and subsequent different data model all work perfectly. I can perform different operations using the 2 data layers with seemingly no consequences. Of course the objectsets are different in the 2 data layers as they represent different tables.
My question is this:
Is this approach a good idea? I get most of what is going on behind the scenes but both of these models use System.Data.Objects.ObjectContext. If user A performs an operation using the first data layer while simultaneously user B performs an operation using the second data layer, are there going to be problems with the "shared" objectcontext?
Thanks. And be gentle.
Edit
Note: I am using different oc keys
You should be OK:
The object context is per http request so the context from different users will not interfere with each other
Each context updates different tables so they will not interfere with each other
One thing that you may have to watch out for is what happens it two users update the same data at the same time.