Dynamic wsdl value for a jax ws web service client - java

Okay. So i'm taking over a very very old system that uses Groovy, and this application is connecting to a third party web service via its configuration file with the entry like this: (this is for prd)
webService.wsdlUrl = "jar:file:/lib/MyWebService.jar!/META-INF/wsdl/MyServices_live.wsdl"
It has its own set of groovy configuration files for qa and prd. Qa looks like this:
webService.wsdlUrl = "jar:file:/lib/MyWebService.jar!/META-INF/wsdl/MyServices_qa.wsdl"
These MyServices_live.wsdl and MyServices_qa.wsdl files contain the path to the actual web service url (for prd and qa respectively) which is the one that needs to be replaced for both instances.
I already have the new url. So what did I do? I don't have enough experience doing this so I had to do some research. Apparently, I can use "wsimport" to connect to the new web service url and append ?wsdl to the end of this url so I can generate a jax-rs web service client. I was able to produce a set of java codes that I eventually learned that theyI thought problem solved. I just need to compile these java codes and jar the classes, so I'll have an updated MyWebService.jar.
Now, I realized with what I have done, the wsdl parameter is embedded in the code
#WebServiceClient(name = "Services", targetNamespace = "http://blahblah/", wsdlLocation = "https://newhostname.com/Service?wsdl")
With this approach, I would create 2 jars, 1 for prd and 1 for qa which won't be the most ideal thing to do. We would like to retain the previous capability of controlling where the web service client (inside the jar) will point to by using a parameter (e.g. just like here... the wsdl was specified jar:file:/lib/MyWebService.jar!/META-INF/wsdl/MyServices_live.wsdl ).
Again, to highlight the architecture, the application is running in Groovy and it is using a jar file to access some third party services.
I haven't really done any Groovy development, so I would like to as much as possible not touch any Groovy code.
Would you have any idea of how i can go about this problem?

Related

Running Lagom in Production

I am working on setting up a Lagom application in production. I have tried contacting Lightbend for ConductR license but haven't heard back in ages. So, now I am looking for an alternative approach. I have multiple questions.
Since the scale of the application is pretty small right now, I think using a static service locator works for me right now (open to other alternatives). Also, I am using MySQL as my event store instead of the default configuration of Cassandra (Reasons not relevant to this thread).
To suppress Cassandra and Lagom's Service Locator, I have added the following lines to my build.sbt:
lagomCassandraEnabled in ThisBuild := false
I have also added the following piece to my application.conf with service1-impl module.
lagom.services {
service1 = "http://0.0.0.0:8080"
}
For the dev environment, I have been able to successfully run my application using sbt runAll in a tmux session. With this configuration, there is no service locator running on the default 8000 port but I can individually hit service1 on 8080 port. (Not sure if this is the expected behaviour. Comments?)
I ran sbt dist to create a zip file and then unzipped it and ran the executable in there. Interestingly, the zip was created within the service1-impl folder. So, if I have multiple modules (services?), will sbt dist create individual zip files for each of the service?
When I run the executable created via sbt dist, it tries to connect to Cassandra and also launches a service locator and ignores the static service locator configuration that I added. Basically, looks like it ignores the lines I added to build.sbt. Anyone who can explain this?
Lastly, if I were to have 2 services, service1 and service2, and 2 nodes in the cluster with node 1 running service1 and node 2 running both the services, how would my static service locator look like in the application.conf and since each of the service would have its own application.conf, would I have to copy the same configuration w.r.t. static service locator in all the application.confs?
Would it be something like this?
lagom.services {
service1 = "http://0.0.0.0:8080"
service1 = "http://1.2.3.4:8080"
service2 = "http://1.2.3.4:8081"
}
Since each specific actor would be spawned on one of the nodes, how would it work with this service locator configuration?
Also, I don't want to run this in a tmux session in production. What would be the best way to finally run this code in production?
You can get started with ConductR in dev mode immediately, for free, without contacting sales. Instructions are at: https://www.lightbend.com/product/conductr/developer
You do need to register (read: provide a valid email) and accept TnC to access that page. The sandbox is free to use for dev mode today so you can see if ConductR is right for you quickly and easily.
For production, I'm thrilled to say that soon you'll be able to deploy up to 3 nodes in production if you register w/Lightbend.com (same as above) and generate a 'free tier' license key.
Lagom is opinionated about microservices. There's always Akka and Play if those opinions aren't shared by a project. Part of that opinion is that deployment should be easy. Good tools feel 'right' in the hand. You are of course free to deploy the app as you like, but be prepared to produce more polyfill the further from the marked trails you go.
Regarding service lookup, ConductR provides redirection for HTTP service lookups for use with 'withFollowRedirects' on Play WS [1]
Regarding sbt dist, each sub-project service will be a package. You can see this in the Chirper example [2] on which sbt dist generates chirp-impl.zip, friend-impl.zip, activity-stream-impl, etc as seen in the Chirper top level build.sbt file.
As that ConductR is the clean and lighted path, you can reference how it does things in order to better understand how to replace Lagom's deployment poly w/ your own. That's the interface Lagom knows best. Much of ConductR except the core is already OSS so can try github if the docs don't cover something.
Disclosure: I am a ConductR-ing Lightbender.
http://conductr.lightbend.com/docs/1.1.x/ResolvingServices
git#github.com:lagom/activator-lagom-java-chirper.git

Communicating to a SOAP webservice with constantly changing targetNamespace

So there is a SOAP webservice. The targetNamespace in the WSDL dynamically changes based on customer's configurable string. Think of it like
targetNamespace="http://myservice."+ [CouldBeAnyString] + "domain.com"
I have two questions:
My basic research tells me that this is a pretty weird(bad?) practice for developing webservices. Thoughts ?
How does one write a client for such a webservice ? I have tested using jax-ws stub and it isn't compatible when targetNamespace changes. Any other suggestions ? I have been trying to understand dynamic client generation based on wsdl. Would prefer a nicer path though if one exists
Update:
I am only the client. Service is provided by someone else.
Same customer has multiple environments (eg test,production) where the service is hosted under different targetNamespaces
If the SOAPUI call works even if the targetNamespace has change, you could use a lightweight HTTP library called HTTPCLIENT.
With this library you don't need to generate client, since you are sending the SOAP envelope as a string, the way you would do via SOAPUI.
The downside is to work with Strings.
In theory, it is feasible to create such a Web Service client.
Steps:
Create Java artifacts based on the WSDL using wsimport.exe of JDK (see: http://www.mkyong.com/webservices/jax-ws/jax-ws-wsimport-tool-example as a reference)
For the purposes of the code displayed below, I have used the Calculator WSDL provided by Microsoft
Create a "Dynamic Web Project" via Eclipse J2EE
Copy the Java artifacts created in step #1, under src folder of the project created in step #2.
Create a new Class containing you main method. Normally you would have something similar to:
String wsdlLocation = "127.0.0.1:8088";//Normally you should retrieve that value dynamically
Url url = new URL(wsdlLocation + "?wsdl");// ?wsdl is actually needed
String namespaceURI = "http://Example.org";//Normally you should retrieve that value dynamically
String localPart = "CalculatorService";// as specified in WSDL file (see name attribute of service tag)
QName qname = new QName(namespaceURI, localPart);
CalculatorService service = new CalculatorService(url,qname);
ICalculator iCalculator = service.getICalculator();
int response = iCalculator.add(1, 2);
System.out.println(response);
Now for the tricky part:
If you have followed the example with the aforementioned WSDL, you should now have several Annotated Classes having hard-coded namespace (e.g. ICalculator is annotated with:
#WebResult(name = "result", targetNamespace = "..."))//where ... is similar to http ://example .org
Using Java reflection modify all the hard-coded values at runtime (see an example here: https://stackoverflow.com/a/14276270/2625635 on how to modify Annotations)
The aforementioned solution should do the trick.
Most client frameworks allow you to create an interface for calling your client (i.e. they create a contract interface). They also provide an implementation for that interface and it is the implementation that has specific annotations or extends "SOAP aware" classes, while the interface is clean of such details.
From what you posted I assume the clients have the same interface, it's just the implementation namespace that's different? If yes, then write your application to use the interface then build a jar for each environment's implementation. When you deploy on test servers deploy with the test jar, while on production deploy with the production jar (i.e. pick a different implementation for the same contract depending on the environment).
Even if the framework you use doesn't create an interface for you, you can create one yourself and hide the various implementations behind an adapter of some sort.
You can also do something like edubriguenti suggested but I wouldn't go as far as working with strings. Work with SAAJ instead.

Can I have multiple Java webapps with overlapping paths?

I have a large collection of different independent (stateless) web services written in Java and compiled as WAR files. I want to deploy them to a single web application server.
If the URIs handled by the services in each WAR file began with a prefix I could use as a web app name, then this would be easy. I could, for instance, have
SALES WAR FILE: contains code for the following:
GET http://example.com/sales/widgets
POST http://example.com/sales/widgets
GET http://example.com/sales/sky-hooks
MARKETING WAR FILE: contains code for the following:
GET http://example.com/marketing/widgets
PUT http://example.com/marketing/sky-hooks
...in which case I would simply deploy two WAR files under the names "sales" and "marketing". However, I am not that fortunate. Instead, the URI paths handled by the components overlap. Something like this:
SALES WAR FILE: contains code for the following:
GET http://example.com/widgets/sales
POST http://example.com/widgets/sales
GET http://example.com/sky-hooks/sales
MARKETING WAR FILE: contains code for the following:
GET http://example.com/widgets/marketing
PUT http://example.com/sky-hooks/marketing
My question is how (if at all) I can deploy these on a single web application server.
I am open to suggestions that require a significant amount of work. For instance, my best-so-far idea is to build services that expect a component-name prefix before the regular URI path, then pipe all incoming traffic through a different server that knows what component each URI pattern falls into and modifies the URI to add that prefix. The difficulty with this approach is that tools like Swagger that read my source code will have a mistaken idea of what the URIs look like.
Any ideas?
If you're willing to put apache in front of your web container, you can use apache's mod_proxy to forward request to the right place.
One way this could work, would be deploy the separate wars at separate prefixes as in your first case (sales and marketing) and then use ProxyPass to send the requests to the correct place:
ProxyPass /widget/sales http://example.com/sales/widget
ProxyPass /sky-hooks/sales http://example.com/sales/sky-hooks
ProxyPass /widget/marketing http://example.com/marketing/widget
ProxyPass /sky-hooks/marketing http://example.com/marketing/sky-hooks
Its probably a better idea to just refactor your routing though - it might be hard to maintain.
(EDIT: I originally suggested mod_rewrite, but I wanted to make my answer more specific, and it looks like this could be done purely with proxying)
If I understand your question correctly, one of the solutions would be (I am assuming Tomcat is used but this should apply to most of the modern servlet containers):
1) Deploy your sales and marketing wars with different prefixes. I.e., using your example, they should be able to serve the following urls:
GET http://example.com/sales/widgets/sales
POST http://example.com/sales/widgets/sales
GET http://example.com/sales/sky-hooks/sales
GET http://example.com/marketing/widgets/marketing
PUT http://example.com/marketing/sky-hooks/marketing
2) Use UrlRewriteFilter to craft lightweight web application that will be deployed to your servlet container root prefix (for Tomcat it is called ROOT.war) and will rewrite urls in incoming requests to point to relevant web application.
In other words, incoming request like:
/widgets/sales
will be transformed to:
/sales/widgets/sales
... and delivered to sales webapp.
Similarly, in response urls like:
/sales/widgets/sales
will be rewritten to:
/widgets/sales
3) Deploy this war to root of your servlet container.
This approach is somewhat similar to the one suggested by #nont but does not require apache as a frontend as the rewriting functionality will be handled by root web application (UrlRewriteFilter basically implements mod_rewrite functionality).
In other words you'll be able to deploy all your applications (including this rewrite application that is deployed to the root prefix) to single server alleviating need for extra intermediate proxy/rewrite servers.
First, Determine How the Deployments may be Configured
Are you sure the absolute URIs must overlap? The context root will prefix the path supported by each service, unless the absolute path has somehow been coded into the application itself. The first step is to enable direct access to each WAR file, either through unique context roots or application instances.
Option 1: Set the Context Root for each WAR File Explicitly
The context root for a war file is set at deploy time. For some servers, this can be set outside of the web application using an external deployment descriptor. For Tomcat, it may embedded within META-INF/context.xml. See http://tomcat.apache.org/tomcat-7.0-doc/config/context.html for more information.
Option 2: Separate the Context Root Instances using Multiple Containers
Alternatively, deploy each war file to a separate instance of a Java EE servlet container, each running on a different port. This will solve the deployment conflict in the case of a hard-coded absolute path.
Finally, Set up a Virtual Host and Proxy the Requests via Apache and mod_jk
Once the context roots instances have been made uniquely accessible by one of the previous methods, configure an instance of Apache to serve as a reverse-proxy. First, set up a virtual host to handle requests for the externally visible URI. Next, configure mod_jk to route the requests to the correct WAR file deployment. See http://tomcat.apache.org/connectors-doc/webserver_howto/apache.html for more details.
Afterthoughts
The above solution approach is generic for this type of problem and will require some knowledge of Apache and Tomcat configuration, which were chosen as example reverse-proxy and Java EE servlet technologies for its implementation. Additional detail on the deployment constraints would help to determine an optimal solution. In general, identifying the hard constraints on what may be changed versus what may not be changed should guide you quickly to a solution.
The obvious slotuion is to rename the wars, or refactor so that the appropriate mappings are in the correct place.
Anything else is going to be a bit hacky, you can't change the war name, even to soemthing like below :
SALES WAR FILE: contains code for the following:
GET http://example.com/webapp1/widgets/sales
POST http://example.com/webapp1/widgets/sales
GET http://example.com/webapp1/sky-hooks/sales
MARKETING WAR FILE: contains code for the following:
GET http://example.com/webapp2/widgets/marketing
PUT http://example.com/webapp2/sky-hooks/marketing
You could also create another war for routing/filtering, that redirects everything appropriately - but that also relies on altering url somewhat.
This is a use case for Reverse Proxy. If your web server is Apache, as suggested by #nont proxy_mod can be used to create a reverse proxy.
I know that IBM Http Server (IHS) also allows this mod.

Avoid project's directory - Java EE app

I am writing and small app using Java EE. I am using Apache Tomcat v 7 and Eclipse as IDE. When I Run the project (Run on server) I get :
http://127.0.0.1:8080/java-web/lis
(That's fine)
But I don't know If there is some way to rewrite the [java-web] dir just to get :
http://my-local-app.dev/list
I suppose there is some way like in Apache Server using confing files and enabling
the mod_rewrite.
I'll apreciate your help. Thanks
In short: All of the pieces you want to change are components of your deployment environment. Unless you have a specific need to override them, it's usually easiest during development to use the URLs that are a little less pretty.
If you do want to alter them, you need to familiarize yourself with what the various parts of an HTTP URL mean. What you have in your test environment is this:
http:// 127.0.0.1:8080/java-web/list
protocol host port path
You could insert an entry into your hosts file listing my-local-app.dev at 127.0.0.1, but that would not change the port or the path.
The port is determined when Tomcat starts up and is 8080 by default. The general port for HTTP is 80, but specific permission is required to bind to ports below 1024. On Linux, the authbind package makes this pretty easy; on Windows, the necessary steps will depend on your version and configuration (e.g., if you have a Group Policy).
In Tomcat, Web applications are prefixed with their names in the path; it looks like your (hypothetical?) application is named java-web.war. You can install an application as the "root application", but this requires a little bit more configuration and is generally skipped in development.
All of this can indeed also be done using something like mod_rewrite, but that seems like overkill to have slightly prettier URLs for your dev machine.
If you want your application to respond to the my-local-app.dev, you need to purchase the "my-local-app.dev" domain and get a Java web hotel running on it.
If your web application is named "java-web" and you do not want the URL to reflect that, you need to tell Tomcat that you want your application deployed at the ROOT location where the name of the web application is not present in the URL. This is typically done in the deployment stage but unfortunately there is no standard location to say this for WAR files so this is vendor dependent. For example does Glassfish use an extra XML file in your deployment.
I believe Tomcat supports this for ROOT.war files. If not, you probably needs to set the META-INF/context.xml file. See https://tomcat.apache.org/tomcat-7.0-doc/config/context.html for details on what to put in this file - especially the context path.

Developing Web services applications from existing WSDL files

I have done this on Websphere (re: title of this topic) using wsdl2java for generating wsdl to java mapping xml file.
My endpoint is a generic stateless EJB. The code in EJB is generated by traversing the each wsdl and getting the wsdl operation and stuck it in the generated remote EJB interface.
Each EJB method impl is generic and handles all the services the same.
Used instructions on this doc to do this on WAS: http://publib.boulder.ibm.com/infocenter/wasinfo/v7r0/index.jsp?topic=/com.ibm.websphere.base.doc/info/aes/ae/twbs_devwbsjaxrpcwsdl.html
Now, I am asking you all for help if anyone has done something similar in Sun AS 9.1.
Starting from existing WSDL (and xsd) files. Knowing the sole EJB service endpoint implementation for each services are the same, and generating an EAR file (webservices.xml, ejb-jar.xml, etc).
Have struggled with wscompile and alike, but not getting anyware in the same fashion I did for WebSphere.
Thanks for help.
You want to create a WS client which runs under Sun AS? I don't know Sun AS in detail and I don't know the WS libraries it supplies. But you may want to use a public WS library:
Apache Axis 2
Apache CXF
For every library there is documentation which describes how to create a project from WSDL.
You could even use Eclipse to create a project from WSDL for you: File -> New -> Other... -> Web Services -> WSDL. Make sure you have the "WST Web Services" Plugins installed.
I've never used it myself, but I just recently read about the wsdlLocation() attribute of the WebService annotation, which is supposed to map the service to a preexisting WSDL document (not sure if you're even using EJB3, though).

Categories

Resources