Develop Reference

Can Jackson/Jax-rs have an optional data?

I am making a curl request to endpoint with following option curl --data {"foo" : "bar"} for POST request
However I want to implement a default behavior for missing data, ie curl without --data should also work for POST request.
Currently if data is missing it returns: "error":400,"errorCode":"INVALID_JSON". I do not want that.
Is it possible ?
Does it have any annotation to support optional data.?

Hyperledger Composer + loopback-datasource-juggler + Java: Encoding Problems

I developed a Business Network Definition with Hyperledger Composer, deployed it on a Hyperledger Fabric example-chain (running locally on a VirtualBox-installation of Ubuntu with Docker-containers) and started Composer's REST-server with composer-rest-server (and options -c [cardname] -n always -w true). Then I played a bit in the browser and all is working fine.
Now comes the problematic bit: I want to write a Java-program interacting with this REST API and somehow the API seems unable to parse my Java-sent requests. I copied the JSON-string that Java produces to the browser, ran it there and it worked fine. But if I send it programmatically I get the error (see at the end).
This is what I send through the browser
{"cId":"C_ID7","cDomain":"example.com"}
The browser tells me with CURL it should look like this
curl -X POST --header 'Content-Type: application/json' --header 'Accept: application/json' -d '{"cId":"C_ID7","cDomain":"example.com"}' 'http://localhost:3000/api/com.example.Company'
Now I want to send the same message through Java+JSOUP with the following code:
Response resp = Jsoup.connect(baseURL + namespace + "Company").ignoreContentType(true).method(Method.POST)
.ignoreHttpErrors(true)
.requestBody("{\"cId\":\"C_ID7\",\"cDomain\":\"example.com\"}").execute();
The same (without the requestBody and Method.GET) works for GET-requests. ignoreContentType(true) is necessary, because JSOUP will not handle 'application/json', see here. ignoreHttpErrors(true) is necessary, to get through the Http 500 error, which conceals the true error, which I need for trouble-shooting.
So then finally what I see, when I execute the above code, is the following error:
{"error":{"statusCode":500,"name":"Error","message":"Property names containing dot(s) are not supported. Model: com_example_Company, dynamic property: {\"cId\":\"C_ID7\",\"cDomain\":\"example.com\"}","stack":"Error: Property names containing dot(s) are not supported. Model: com_example_Company, dynamic property: {\"cId\":\"C_ID7\",\"cDomain\":\"example.com\"}\n at com_example_Company.ModelBaseClass._initProperties
(/home/[user]
]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/loopback-datasource-juggler/lib/model.js:249:17)\n
at com_example_Company.ModelBaseClass (/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/loopback-datasource-juggler/lib/model.js:60:8)\n
at com_example_Company.Model (eval at createModelClassCtor
(/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/loopback-datasource-juggler/lib/model-builder.js:671:21), <anonymous>:12:24)\n
at com_example_Company.PersistedModel (eval at createModelClassCtor
(/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/loopback-datasource-juggler/lib/model-builder.js:671:21), <anonymous>:12:24)\n
at new com_example_Company (eval at createModelClassCtor
(/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/loopback-datasource-juggler/lib/model-builder.js:671:21), <anonymous>:12:24)\n
at Function.DataAccessObject.create (/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/loopback-datasource-juggler/lib/dao.js:359:13)\n
at SharedMethod.invoke
(/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/lib/shared-method.js:270:25)\n
at HttpContext.invoke (/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/lib/http-context.js:297:12)\n
at phaseInvoke (/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/lib/remote-objects.js:676:9)\n at runHandler
(/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/node_modules/loopback-phase/lib/phase.js:135:5)\n
at iterate (/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/node_modules/loopback-phase/node_modules/async/lib/async.js:146:13)\n
at Object.async.eachSeries
(/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/node_modules/loopback-phase/node_modules/async/lib/async.js:162:9)\n
at runHandlers (/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/node_modules/loopback-phase/lib/phase.js:144:13)\n
at iterate
(/home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/node_modules/loopback-phase/node_modules/async/lib/async.js:146:13)\n
at /home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/node_modules/loopback-phase/node_modules/async/lib/async.js:157:25\n
at /home/[user]/.nvm/versions/node/v8.9.4/lib/node_modules/composer-rest-server/node_modules/strong-remoting/node_modules/loopback-phase/node_modules/async/lib/async.js:154:25"}}
where obviously [user] is my username. So I had a look at the loopback-datasource-juggler sources and found that in model-builder.js (source on Github) instead of parsing the different properties of the string, it is given the complete string ("{\"cId\":\"C_ID7\",\"cDomain\":\"example.com\"). In line 269 the builder checks whether there are dot-characters in the property-name. Since in our case the property name is the complete JSON-string, there are dots and the program fails.
Unfortunately XML does not seem to be supported at this point.
Now: How can this happen? My only guess is an encoding thing done by Java, because the same JSON works in the browser. Any ideas what could have caused this?
And one smaller issue: The error message in the code is ''Property names containing dot(s) are not supported. ' + 'Model: %s, property: %s'', but in the error I receive it says something about "dynamic property". Am I at the wrong point for searching what causes the error?

Since you have already specified 'Content-Type: application/json', you needn't have double quotes in the requestBody. The following should work:
Response resp = Jsoup.connect(baseURL + namespace + "Company").ignoreContentType(true).method(Method.POST)
.ignoreHttpErrors(true)
.requestBody({\"cId\":\"C_ID7\",\"cDomain\":\"example.com\"}).execute();

the curl example is what the REST APIs (rather than merely the browser) know about the business network REST API endpoints.
for your requestBody, you will need the fully qualified class (ie meaning asset/participant/transaction class with leading namespace) - an example is :
curl -X POST --header 'Content-Type: application/json' --header 'Accept: application/json' -d '{ \
"$class": "org.example.biznet.SampleAsset", \
"assetId": "1", \
"value": "103300" \
}' 'http://localhost:3000/api/SampleAsset'
So yours will be something like
Response resp = Jsoup.connect(baseURL + namespace + "Company").ignoreContentType(true).method(Method.POST)
.ignoreHttpErrors(true)
.requestBody("{\"\$class\": \"org.example.biznet.SampleAsset\", \"cId\":\"C_ID7\", \"cDomain\":\"example.com\"}").execute();
I believe you also needed at least one other double-quotes (total above now : 14) and a closing curly bracket in addition.

Watson Natural Language Understanding Java 401-not authorized

I'm trying to connect my Java application to the Watson NLU service. For a start, I tried to follow the tutorial from Bluemix. I created a service on Bluemix and imported the watson Java SDK. Using this tutorial code, I keep receiving 401 - not authorized responses. (Of course i changed username and password for the service).
I guess there's something missing, but i can't figure out what.
NaturalLanguageUnderstanding service = new NaturalLanguageUnderstanding(
NaturalLanguageUnderstanding.VERSION_DATE_2017_02_27,
"{username}",
"{password}"
);
String text = "IBM is an American multinational technology " +
"company headquartered in Armonk, New York, " +
"United States, with operations in over 170 countries.";
EntitiesOptions entitiesOptions = new EntitiesOptions.Builder()
.emotion(true)
.sentiment(true)
.limit(2)
.build();
KeywordsOptions keywordsOptions = new KeywordsOptions.Builder()
.emotion(true)
.sentiment(true)
.limit(2)
.build();
Features features = new Features.Builder()
.entities(entitiesOptions)
.keywords(keywordsOptions)
.build();
AnalyzeOptions parameters = new AnalyzeOptions.Builder()
.text(text)
.features(features)
.build();
AnalysisResults response = service
.analyze(parameters)
.execute();
System.out.println(response);

i had the same problems in node.js and solved it by adding the correct url of the api gateway to the NaturalLanguageUnderstanding service = new NaturalLanguageUnderstanding() object.
please keep in mind, that this depends on your region ..
regards
Leo

A 401 Unauthorized would suggest that there's an issue with the credentials that you're using to access the service. To rule this out, take a start by using the cURL tutorial from that same page:
curl -X POST \
-H "Content-Type: application/json" \
-u "{username}":"{password}" \
-d #parameters.json "https://gateway.watsonplatform.net/natural-language-understanding/api/v1/analyze?version=2017-02-27"
If, with that same username and password, you still receive a 401 Unauthorized error, then there's likely an issue with that username/password combination. Delete the tile in Bluemix and create a new one to get a new username/password, and give that a try.
If that does work fine, then there's an issue with how the username/password is being inserted into the code. Verify that you've replaced {username} and {password}, the final version should not have any curly brackets in it.

Cannot call Bitcoin RPC from Jersey HttpClient

im using dropwizard. From a resource i try to use bitcoin rpc via Jersey HttpClient.
using curl works like a charm:
$ curl --user user:password -X POST -d '{"jsonrpc": "1.0", "id":"curltest", "method": "getinfo", "params":
[] }' -H 'content-type: text/plain;' http://domain.name:18332/
But somehow using Jersey HTTP client from a resource doesnt work:
//init in run methode
final Client client = new JerseyClientBuilder(e).using(c.getJerseyClientConfiguration()).build(getName());
HTTPBasicAuthFilter httpBasicAuth = new HTTPBasicAuthFilter("user", "password");
client.addFilter(httpBasicAuth);
//From the resource
WebResource webRes = client.resource("http://domain.name:18332/");
webRes.header("content-type", "text/plain");
RPC_REQUEST rpc = new RPC_REQUEST("1.0", "curltest", "getinfo", new ArrayList<String>());
String response = webRes.post(String.class, JSONParserHelper.parseJSONToString(rpc));
JSONParserHelper.parseJSONToString(rpc) returns following string:
{"jsonrpc":"1.0","id":"curltest","method":"getinfo","params":[]}
Following error is caused in row "webRes.post":
! com.sun.jersey.api.client.UniformInterfaceException: Client response status: 500
EDIT: Using a wrong pw causes a 401. I guess the connection should be correct and the issue is somewhere else.
EDIT: Used -d instead of --data-binary
EDIT: As soon as Im home Ill dump the whole request from jersey http client.
Thank you

Bitcoin RPC does not support chunked encoding requests.
Since there was a bug in dropbox jersey libs till 0.8 you cannot disable it.
Since 0.8 you can disable it in the configuration file.
I had to migrate from 0.7 to 0.8 and add this in my configuration file.
httpClient:
...
chunkedEncodingEnabled: false
By the way a good migration overview: https://groups.google.com/forum/#!topic/dropwizard-dev/VInOW_ebiAc

This API does not support parsing form-encoded input

I tried to submit data to an endpoint but it said the data size was too large, so I changed the method to POST and received the error:
This API does not support parsing form-encoded input.
Next I changed the type to application/json, still with post and now I am getting:
{
"error": {
"errors": [
{
"domain": "global",
"reason": "parseError",
"message": "Parse Error"
}
],
"code": 400,
"message": "Parse Error"
}
}
What is the best way to post a large amount of data, i.e. 2730 bytes to an endpoint and have it handle it properly? In my case the field in question is of type Text as I am over the 500 character limit for app engine to hold in a String.
Also, as with many things, this works great on my local machine, it only gives this error on the live app engine instance.
Thanks!

Not sure if your problem is related, but I received the "This API does not support parsing form-encoded input." error when I was attempting to use curl to send a POST message like this:
curl -X POST -d '{"name": "Foo"}' http://foo.appspot.com/_ah/api/foo/1/endpoint
The problem was that I was not setting the content type. curl POSTs with Content-Type: application/x-www-form-urlencoded if it's not specified on the command line. Google cloud endpoints don't accept this content type.
When I changed the curl invocation to include the content type, it worked:
curl -X POST -d '{"name": "Foo"}' --header "Content-Type: application/json" http://foo.appspot.com/_ah/api/foo/1/endpoint