I am trying to avoid some naming conflicts in my uploaded files (I used com.oreilly.servlet.MultipartRequest ).
At this moment my constructor looks like this:
MultipartRequest multi = new MultipartRequest(request, uploadPath);
I would like to implement the constructor with FileRenamePolicy in order to rename my file with a value taken from a form (something like request.getParameterValue("title");
I think I should use the foloowing constructor? But I don't know how to set the "policy" paramter
MultipartRequest(javax.servlet.http.HttpServletRequest request,
java.lang.String saveDirectory,
int maxPostSize,
java.lang.String encoding,
FileRenamePolicy policy)
Do you have any suggestions?
Thanks!
You should implement a custom FileRenamePolicy which gives you the File appending the title sent along with the request.
Here is what you are looking for:
private static class MyTitleRenamePolicy extends FileRenamePolicy {
java.io.File rename(java.io.File f) {
return new File(f.getParentFile(),
rename.getName() + "_"+ request.getParameter("title"));
}
}
new MultipartRequest(request, saveDirectory, maxPostSize, encoding,
new MyTitleRenamePolicy(request));
Related
I'm trying to implement an RSS/Atom feed aggregator in spring-integration and I am primarily using the Java DSL to write my IntegrationFlow. A requirement of this aggregator is that feeds can be added / removed during runtime. That is to say, the feeds are not known at design time.
I found it simple to use the basic Feed.inboundAdapter() with a test url and extract the links out of the feed with a transformer and then pass it on to an outbound-file-adapter to save the links to a file. However, I have gotten very stuck when trying to read the (thousands) of feed urls from an inbound-file-adapter run the file through a FileSplitter and then pass each resulting Message<String> containing the feed url to then register a new Feed.inboundAdapter(). Is this not possible with the Java DSL?
Ideally I would love it if I could do the following:
#Bean
public IntegrationFlow getFeedsFromFile() throws MalformedURLException {
return IntegrationFlows.from(inboundFileChannel(), e -> e.poller(Pollers.fixedDelay(10000)))
.handle(new FileSplitter())
//register new Feed.inboundAdapter(payload.toString()) foreach Message<String> containing feed url coming from FileSplitter
.transform(extractLinkFromFeedEntry())
.handle(appendLinkToFile())
.get();
}
Though after reading through the spring integration java DSL code multiple times (and learning a tonne of stuff along the way) I just can't see that it's possible to do it this way. So... A) is it? B) should it be? C) Suggestions?
It almost feels like I should be able to take the output of .handle(new FileSplitter()) and pass that into .handleWithAdapter(Feed.inboundAdapter(/*stuff here*/)) but the DSL only references outbound-adapters there. Inbound adapters are really just a subclass of AbstractMessageSource and it seems the only place you can specify one of those is as an argument to the IntegrationFlows.from(/*stuff here*/) method.
I would have thought it would be possible to take the input from a file, split it line by line, use that output to register inbound feed adapters, poll those feeds, extract the new links from feeds as they appear and append them to a file. It appears as though it's not.
Is there some clever subclassing I can do to make this work??
Failing that... and I suspect this is going to be the answer, I found the spring integration Dynamic Ftp Channel Resolver Example and this answer on how to adapt it dynamically register stuff for the inbound case...
So is this the way to go? Any help/guidance appreciated. After pouring over the DSL code and reading documentation for days, I think I'll have a go at implementing the dynamic ftp example and adapting it to work with FeedEntryMessageSource... in which case my question is... that dynamic ftp example works with XML configuration, but is it possible to do it with either Java config or the Java DSL?
Update
I've implemented the solution as follows:
#SpringBootApplication
class MonsterFeedApplication {
public static void main(String[] args) throws IOException {
ConfigurableApplicationContext parent = SpringApplication.run(MonsterFeedApplication.class, args);
parent.setId("parent");
String[] feedUrls = {
"https://1nichi.wordpress.com/feed/",
"http://jcmuofficialblog.com/feed/"};
List<ConfigurableApplicationContext> children = new ArrayList<>();
int n = 0;
for(String feedUrl : feedUrls) {
AnnotationConfigApplicationContext child = new AnnotationConfigApplicationContext();
child.setId("child" + ++n);
children.add(child);
child.setParent(parent);
child.register(DynamicFeedAdapter.class);
StandardEnvironment env = new StandardEnvironment();
Properties props = new Properties();
props.setProperty("feed.url", feedUrl);
PropertiesPropertySource pps = new PropertiesPropertySource("feed", props);
env.getPropertySources().addLast(pps);
child.setEnvironment(env);
child.refresh();
}
System.out.println("Press any key to exit...");
System.in.read();
for (ConfigurableApplicationContext child : children) {
child.close();
}
parent.close();
}
#Bean
public IntegrationFlow aggregateFeeds() {
return IntegrationFlows.from("feedChannel")
.transform(extractLinkFromFeed())
.handle(System.out::println)
.get();
}
#Bean
public MessageChannel feedChannel() {
return new DirectChannel();
}
#Bean
public AbstractPayloadTransformer<SyndEntry, String> extractLinkFromFeed() {
return new AbstractPayloadTransformer<SyndEntry, String>() {
#Override
protected String transformPayload(SyndEntry payload) throws Exception {
return payload.getLink();
}
};
}
}
DynamicFeedAdapter.java
#Configuration
#EnableIntegration
public class DynamicFeedAdapter {
#Value("${feed.url}")
public String feedUrl;
#Bean
public static PropertySourcesPlaceholderConfigurer pspc() {
return new PropertySourcesPlaceholderConfigurer();
}
#Bean
public IntegrationFlow feedAdapter() throws MalformedURLException {
URL url = new URL(feedUrl);
return IntegrationFlows
.from(s -> s.feed(url, "feedTest"),
e -> e.poller(p -> p.fixedDelay(10000)))
.channel("feedChannel")
.get();
}
}
And this works IF and only IF I have one of the urls defined in application.properties as feed.url=[insert url here]. Otherwise it fails telling me 'unable to resolve property {feed.url}'. I suspect what is happening there is that the #Beans defined in DynamicFeedAdapter.java all get singletons eagerly initialized, so aside from the beans being manually created in our for loop in the main method (which work fine because they have feed.url property injected) we have a stray singleton that has been eagerly initialized and if there is no feed.url defined in application.properties then it can't resolve the property and everything goes bang. Now from what I know of Spring, I know it should be possible to #Lazy initialize the beans in DynamicFeedAdapter.java so we don't wind up with this one unwanted stray singleton problem-child. The problem is now...if I just mark the feedAdapter() #Lazy then the beans never get initialized. How do I initialize them myself?
Update - problem solved
Without having tested it, I think the problem is that boot is finding
the DynamicFeedAdapter during its component scan. A simple solution is
to move it to a sibling package. If MonsterFeedApplication is in
com.acme.foo, then put the adapter config class in com.acme.bar. That
way, boot won't consider it "part" of the application
This was indeed the problem. After implementing Gary's suggestion, everything works perfect.
See the answer to this question and its follow up for a similar question about inbound mail adapters.
In essence, each feed adapter is created in a child context that is parameterized.
In that case the child contexts are created in a main() method but there's no reason it couldn't be done in a service invoked by .handle().
`I need to contact an API which requires that every request contain the signature of all parameters and url + nonce.
Example:
#GET("/users/{type}")
public void getUsers(
#Path("type") String type,
#Query("sort") boolean sort)
I should add a X-Signature header with contains signature(nonce+"/users/"+type+"sort="+sort).
I thought I could do this with a RequestInterceptor's addHeader(String name, String value) but I can`t as the signature varies for every request.
Is there a smart way to do this with Retrofit or will I just have to manually sign every request?
Am I right in thinking that your signature is generated from [nonce]+[path]+[query params]
You could look at implementing a custom client and passing this into your RestAdapter.Builder().setClient(new CustomClient) method.
Something like CustomClient extends OkClient and then override the execute(Request) method. You will need to create a new Request object and pass that to super.execute(updatedRequest).
#Override
public Response execute(Request request) throws IOException {
List<Header> headers = new ArrayList<>();
// do work here to parse the request.getUrl() and extract path/params and generate the signature
headers.addAll(request.getHeaders());
headers.add(new Header("X-Signature", "signature"));
Request updated = new Request(request.getMethod(), request.getUrl(), headers, request.getBody());
return super.execute(updated);
}
If however there is no consistency to the generation of the signature then you will need to create the signature manually and add a #Header value in your call to your client.
I have a webforms project, and am attempting to run some code that allows me to make a call to an MVC route and then render the result within the body of the web forms page.
There are a couple of HttpResponse/Request/Context wrappers which I use to execute a call to an MVC route, e.g.:
private static string RenderInternal(string path)
{
var responseWriter = new StringWriter();
var mvcResponse = new MvcPlayerHttpResponseWrapper(responseWriter, PageRenderer.CurrentPageId);
var mvcRequest = new MvcPlayerHttpRequestWrapper(Request, path);
var mvcContext = new MvcPlayerHttpContextWrapper(Context, mvcResponse, mvcRequest);
lock (HttpContext.Current)
{
new MvcHttpHandlerWrapper().PublicProcessRequest(mvcContext);
}
...
The code works fine for executing simple MVC routes, for e.g. "/Home/Index". But I can't specify any query string parameters (e.g. "/Home/Index?foo=bar") as they simply get ignored. I have tried to set the QueryString directly within the RequestWrapper instance, like so:
public class MvcPlayerHttpRequestWrapper : HttpRequestWrapper
{
private readonly string _path;
private readonly NameValueCollection query = new NameValueCollection();
public MvcPlayerHttpRequestWrapper(HttpRequest httpRequest, string path)
: base(httpRequest)
{
var parts = path.Split('?');
if (parts.Length > 1)
{
query = ExtractQueryString(parts[1]);
}
_path = parts[0];
}
public override string Path
{
get
{
return _path;
}
}
public override NameValueCollection QueryString
{
get
{
return query;
}
}
...
When debugging I can see the correct values are in the "request.QueryString", but the values never get bound to the method parameter.
Does anyone know how QueryString values are used and bound from an http request to an MVC controller action?
It seems like the handling of the QueryString value is more complex than I anticipated. I have a limited knowledge of the internals of the MVC Request pipeline.
I have been trying to research the internals myself and will continue to do so. If I find anything I will update this post appropriately.
I have also created a very simple web forms project containing only the code needed to produce this problem and have shared it via dropbox: https://www.dropbox.com/s/vi6erzw24813zq1/StackMvcGetQuestion.zip
The project simply contains one Default.aspx page, a Controller, and the MvcWrapper class used to render out the result of an MVC path. If you look at the Default.aspx.cs you will see a route path containing a querystring parameter is passed in, but it never binds against the parameter on the action.
As a quick reference, here are some extracts from that web project.
The controller:
public class HomeController : Controller
{
public ActionResult Index(string foo)
{
return Content(string.Format("<p>foo = {0}</p>", foo));
}
}
The Default.aspx page:
protected void Page_Load(object sender, EventArgs e)
{
string path = "/Home/Index?foo=baz";
divMvcOutput.InnerHtml = MvcWrapper.MvcPlayerFunctions.Render(path);
}
I have been struggling with this for quite a while now, so would appreciate any advice in any form. :)
MVC framework will try to fill the values of the parameters of the action method from the query string (and other available data such as posted form fields, etc.), that part you got right. The part you missed is that it does so by matching the name of the parameter with the value names passed in. So if you have a method MyMethod in Controller MyController with the signature:
public ActionResult MyMethod(string Path)
{
//Some code goes here
}
The query string (or one of the other sources of variables) must contain a variable named "Path" for the framework to be able to detect it. The query string should be /MyController/MyMethod?Path=Baz
Ok. This was a long debugging session :) and this will be a long response, so bear with me :)
First how MVC works. When you call an action method with input parameters, the framework will call a class called "DefaultModelBinder" that will try and provide a value for each basic type (int, long, etc.) and instance of complex types (objects). This model binder will depend on something called the ValueProvider collection to look for variable names in query string, submitted forms, etc. One of the ValueProviders that interests us the most is the QueryStringValueProvider. As you can guess, it gets the variables defined in the query string. Deep inside the framework, this class calls HttpContext.Current to retrieve the values of the query string instead of relying on the ones being passed to it. In your setup this is causing it to see the original request with localhost:xxxx/Default.aspx as the underlying request causing it to see an empty query string. In fact inside the Action method (Bar in your case) you can get the value this.QueryString["variable"] and it will have the right value.
I modified the Player.cs file to use a web client to make a call to an MVC application running in a separate copy of VS and it worked perfectly. So I suggest you run your mvc application separately and call into it and it should work fine.
I am just learning actionscript, so come across the problem
In my application I often call to different web services, and because I don't want to hardcode urls to them in my code, I am passing urls to the services as flashvars.
Currently I am doing it this way:
public var siteUrl:String;
public var gameId:String;
public function main():void
{
siteUrl = Application.application.parameters.siteurl;
gameId = Application.application.parameters.gameid;
Where main is a function, which is called on application's creation complete event.
This way I can call both variables from main file of the application but I want to access them from other files. (other as classes)
So is there a way to create class with constants and init values there with flashvars so I can use them everywhere (after importing of course)
The parameters are just stored in that Application.application.parameters object, and that's static. There's no reason you couldn't access that from other classes in your code.
If you want to write a class that wraps the parameters (maybe validates them or something) you could do that fairly easily. You can use a for each loop to loop over all the parameters. Something like:
var params:Object = Application.application.parameters
for(var name:String in params) {
var value:String = params[name] as String;
/* do something with the param */
}
If you want your class to actually verify things then it could just check for each parameter it expects and store it in a local variable.
It really just depends on your own preferences. Some people are fine with accessing the parameters object when they need it. Some people like having the extra code-completion by having a config class that actually defines all the expected config variables.
Update in response to comment:
Instead of having one module declare the variable and have other modules have to depend on that one to access the property it would be cleaner to have a single config module that everything that needs it would all use.
You could use a static class or singleton or some IoC stuff. Just for simplicity I'll show you a way you can do it with a static class.
class MyConfig {
private static var _infoService:String;
private static var _someOtherParam:int;
public static function get infoService():String { return _infoService; }
public static function get someOtherParam():int { return _someOtherParam; }
public static function initParams():Void {
var params:Object = Application.application.parameters;
_infoService = params.infoservice;
// just assuming you have a method to convert here. don't remember the
// code off the top of my head
_someOtherParam = convertToInt(params.someOtherParam);
}
}
Make sure when your app initializes it calls MyConfig.initParams(). You can have that method actually validate that it gets everything it expects and throw exceptions (or return an error) if there's a failure if you want.
Then wherever you need to use that config within your code you just import your config class and access the param. So getting infoService would just be:
var infoService:String = MyConfig.infoService;
Personally I wouldn't use a static class, but it was the easiest to show.
I have a list of error codes I need to reference, kinda like this:
Code / Error Message
A01 = whatever error
U01 = another error
U02 = yet another error type
I get the Code returned to me via a web service call and I need to display or get the readable error. So I need a function when passed a Code that returns the readable description. I was just going to do a select case but thought their might be a better way. What is the best way / most effieient way to do this?
Use a Dictionary, (in C#, but the concept and classes are the same):
// Initialize this once, and store it in the ASP.NET Cache.
Dictionary<String,String> errorCodes = new Dictionary<String,String>();
errorCodes.Add("A01", "Whatever Error");
errorCodes.Add("U01", "Another Error");
// And to get your error code:
string ErrCode = errorCodes[ErrorCodeFromWS];
You would use a dictionary. A dictionary uses a hashmap internally for performance, so it is good in that regard. Also, because you want this to go as quickly as possible by the sounds of it, I would statically initialize it in its own class instead of, for example, in an XML file or slimier. You would probably want something like:
public static class ErrorCodes
{
private static Dictonary<string, string> s_codes = new Dicontary<string, string>();
static ErrorCodes()
{
s_codes["code"] = "Description";
s_codes["code2"] = "Description2";
}
public static string GetDesc(string code)
{
return s_codes[code];
}
}
That way, if you wanted to move the back end to a file instead of being static, then you could.