Spring Boot Get Request with JSON [duplicate] - java

I am trying to access the contents of an API and I need to send a URL using RestTemplate.
String url1 = "http://api.example.com/Search?key=52ddafbe3ee659bad97fcce7c53592916a6bfd73&term=&limit=100&sort={\"price\":\"desc\"}";
OutputPage page = restTemplate.getForObject(url1, OutputPage .class);
But, I am getting the following error.
Exception in thread "main" java.lang.IllegalArgumentException: Not enough variable values available to expand '"price"'
at org.springframework.web.util.UriComponents$VarArgsTemplateVariables.getValue(UriComponents.java:284)
at org.springframework.web.util.UriComponents.expandUriComponent(UriComponents.java:220)
at org.springframework.web.util.HierarchicalUriComponents.expandInternal(HierarchicalUriComponents.java:317)
at org.springframework.web.util.HierarchicalUriComponents.expandInternal(HierarchicalUriComponents.java:46)
at org.springframework.web.util.UriComponents.expand(UriComponents.java:162)
at org.springframework.web.util.UriTemplate.expand(UriTemplate.java:119)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:501)
at org.springframework.web.client.RestTemplate.getForObject(RestTemplate.java:239)
at hello.Application.main(Application.java:26)
If I remove the sort criteria, it is working properly.
I need to parse the JSON using sort criteria.
Any help will be much appreciated.
Thanks

The root cause is that RestTemplate considers curly braces {...} in the given URL as a placeholder for URI variables and tries to replace them based on their name. For example
{pageSize}
would try to get a URI variable called pageSize. These URI variables are specified with some of the other overloaded getForObject methods. You haven't provided any, but your URL expects one, so the method throws an exception.
One solution is to make a String object containing the value
String sort = "{\"price\":\"desc\"}";
and provide a real URI variable in your URL
String url1 = "http://api.example.com/Search?key=52ddafbe3ee659bad97fcce7c53592916a6bfd73&term=&limit=100&sort={sort}";
You would call your getForObject() like so
OutputPage page = restTemplate.getForObject(url1, OutputPage.class, sort);
I strongly suggest you do not send any JSON in a request parameter of a GET request but rather send it in the body of a POST request.

If the solution suggested by sotirios-delimanolis is a little difficult to implement in a scenario, and if the URI string containing curly braces and other characters is guaranteed to be correct, it might be simpler to pass the encoded URI string to a method of RestTemplate that hits the ReST server.
The URI string can be built using UriComponentsBuilder.build(), encoded using UriComponents.encode(), and sent using RestTemplate.exchange() like this:
public ResponseEntity<Object> requestRestServer()
{
HttpEntity<?> entity = new HttpEntity<>(requestHeaders);
UriComponentsBuilder builder = UriComponentsBuilder.fromUriString(rawValidUrl)
.queryParams(
(LinkedMultiValueMap<String, String>) allRequestParams);
UriComponents uriComponents = builder.build().encode();
ResponseEntity<Object> responseEntity = restTemplate.exchange(uriComponents.toUri(), HttpMethod.GET,
entity, String.class);
return responseEntity;
}
Building, encoding, and extracting URI have been seperated out for clarity in the above code snippet.

You can URL encode the parameter values:
String url1 = "http://api.example.com/Search?key=52ddafbe3ee659bad97fcce7c53592916a6bfd73&term=&limit=100&sort=";
org.apache.commons.codec.net.URLCodec codec = new org.apache.commons.codec.net.URLCodec();
url1 = url1 + codec.encode("{\"price\":\"desc\"}");
OutputPage page = restTemplate.getForObject(url1, OutputPage.class);

You can set a specific UriTemplateHandler in your restTemplate. This handler would just ignore uriVariables :
UriTemplateHandler skipVariablePlaceHolderUriTemplateHandler = new UriTemplateHandler() {
#Override
public URI expand(String uriTemplate, Object... uriVariables) {
return retrieveURI(uriTemplate);
}
#Override
public URI expand(String uriTemplate, Map<String, ?> uriVariables) {
return retrieveURI(uriTemplate);
}
private URI retrieveURI(String uriTemplate) {
return UriComponentsBuilder.fromUriString(uriTemplate).build().toUri();
}
};
restTemplate.setUriTemplateHandler(skipVariablePlaceHolderUriTemplateHandler);

You can encode url before using RestTemplate
URLEncoder.encode(data, StandardCharsets.UTF_8.toString());

You can simply append a variable key to the URL and give the value using the restTemplate.getForObject() method.
Example:
String url = "http://example.com/api?key=12345&sort={data}";
String data="{\"price\":\"desc\"}";
OutputPage page = restTemplate.getForObject(url, OutputPage.class, data);

Related

Spring Conversion Magic

I am having a piece of code like below for calling one of our service.
MultiValueMap<String, String> parametersMap = new LinkedMultiValueMap<>();
parametersMap.add("query", query);
parametersMap.add("locale", "en_US");
parametersMap.add("resultsLimit", Boolean.FALSE.toString());
parametersMap.add("maxResults", maxResults);
parametersMap.add("type", "TTT");
parametersMap.add("ids", commaSeparatedValues(ids));
parametersMap.add("infoTypes", "HHH,JJJ");
HttpEntity<MultiValueMap<String, String>> httpEntity = new HttpEntity<>(parametersMap, getHttpHeaders());
MyEntity myEntity = restTemplate.postForEntity("http://example.com", httpEntity, MyEntity.class);
And at the server side the controller code is like
#RequestMapping("my/service")
public MyEntity suggest(#RequestParam(required = true) String query, #RequestParam(required = true) String locale,
#RequestParam(required = false) String resultsLimit, #Valid OtherOptions options)
and the OtherOption class is like
class OtherOptions {
String maxResults;
String type;
String ids;
String infoTypes;
}
Here everything is working fine, but I am confused about somethings like .
Is it a get or post request ?
How is some of the parameter maps content become request params(query params) and some others got mapped to the Object of OtherOptions ?
Which is the actual body of the request ?
Is it a get or post request ?
It is a post request. you are calling restTemplate.postForEntity. But your server side method is not restricted as you didn't specify the method attribute for RequestMapping so same method can handle any http method from the point of server.
How is some of the parameter maps content become request params(query params) and some others got mapped to the Object of OtherOptions?
None of them are query params.
See the spring docs for the meaning of #RequestParam. In your case, it all comes from body and not as query params
https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/bind/annotation/RequestParam.html
https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/client/RestTemplate.html#postForEntity-java.net.URI-java.lang.Object-java.lang.Class-
The body of the entity, or request itself, can be a MultiValueMap to create a multipart request.
Which is the actual body of the request?
parametersMap is the body of the http request.
Note:
Currently your call should fail because you are posting it to http://example.com at client and listening at server side on my/service

Can I get a ResponseEntity (Spring) parametrized with a type either parametrized?

I'm using RestTemplate and SpringBoot 2.0.
I have this class which represents a custom JSON response to rest calls.
MyCustomResponse<T> {
private T content;
public T getContent() {
return content;
}
}
The code snippet below is a example of use:
String LOCALHOST = "http://localhost:8900";
final HttpHeaders headers = new HttpHeaders();
headers.add(HttpHeaders.ACCEPT, "application/json");
String url = String.format("%s/ticket/%s", LOCALHOST, protocol);
final HttpEntity<Ticket> request = new HttpEntity<>(headers);
This works fine:
ResponseEntity<MyCustomResponse> response =
testRestTemplate.getForEntity(url, RespostaPadrao.class);
But it's not what I need, because getContent returns a object that looks like:
Map< Map < String, Map < String, Map < String, Map < String, Integer >>>>>
and because I want to test a Ticket object instead.
In this line, can I use reflection to parametrize the response or this is impossible?
ResponseEntity<MyCustomResponse> response =
testRestTemplate.getForEntity(url, MyCustomResponse.class);
I know how to fix it with ResponseEntity<String> and parse the JSON to my Ticket. But what I really need is know if is possible delegate this task to RestTemplate or not.
Thanks!

How to consume a HTTPS GET service with Spring Boot

I am trying to consume the following HTTPS endpoints from Yahoo Weather Service:
Yahoo Weather Service API
I am doing some special query according to the API to get the current weather at some parametrized location.
#Service("weatherConditionService")
public class WeatherConditionServiceImpl implements WeatherConditionService {
private static final String URL = "http://query.yahooapis.com/v1/public/yql";
public WeatherCondition getCurrentWeatherConditionsFor(Location location) {
RestTemplate restTemplate = new RestTemplate();
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.append(URL);
stringBuilder.append("?q=select%20item.condition%20from%20weather.forecast%20where%20woeid%20in%20(select%20woeid%20from%20geo.places(1)%20where%20text%3D%22");
// TODO: Validate YQL query injection
stringBuilder.append(location.getName());
stringBuilder.append("%22)&format=json&env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys");
WeatherQuery weatherQuery = restTemplate.getForObject(stringBuilder.toString(), WeatherQuery.class);
// TODO: Test Json mapping response
Condition condition = weatherQuery.getQuery().getResults().getChannel().getItem().getCondition();
return new WeatherCondition(condition.getDate(), Integer.parseInt(condition.getTemp()), condition.getText());
}
Location is a class that provides the attribute "name" that is a String description of the location, such as "New York" or "Manila".
Condition an other classes just map the returning object.
When executing I get the following HTTP response:
org.springframework.web.client.HttpClientErrorException: 403 Forbidden
So this means I am not authorized to access the resource from what I understand.
The URL works great if I just copy & paste it in a web browser:
Yahoo Weather Query
I think that mapping is not a problem since I am not getting "400" (Bad Request) but "403" (Forbidden)
There must be some error on the way I use the RestTemplate object. I am researching but I can't find an answer.
The docs say you need an api key. But when I make a call like this:
fetch('https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20weather.forecast%20where%20woeid%20in%20(select%20woeid%20from%20geo.places(1)%20where%20text%3D%22nome%2C%20ak%22)&format=json&env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys')
.then(resp=> resp.json())
.then((res)=>console.log(res.query.results))
https://repl.it/NeoM
It works fine without one. Perhaps you've been blackisted for hitting the api too often.
Your code seems fine.
I finally found the answer. It finally WAS a Bad Request because I needed to pass the parameters differently (not as part of the URL).
I found the answer here. Here goes the code for my particular Yahoo Weather API call return a String (I still will have to do some work to use the mapping).
private static final String URL = "http://query.yahooapis.com/v1/public/yql";
public String callYahooWeatherApi() {
RestTemplate restTemplate = new RestTemplate();
HttpHeaders headers = new HttpHeaders();
headers.set("Accept", MediaType.APPLICATION_JSON_VALUE);
UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(URL)
.queryParam("q", "select wind from weather.forecast where woeid=2460286")
.queryParam("format", "json");
HttpEntity<?> entity = new HttpEntity<>(headers);
HttpEntity<String> response = restTemplate.exchange(
builder.build().encode().toUri(),
HttpMethod.GET,
entity,
String.class);
return response.getBody();
}

java Restful web service get the data from textbox in POST action

I am new to Restful web service in java and this is my first web application, I searched a lot but everybody asking more complicated question than what I need.
I have a pretty simple html with a textbox and a submit button. Also I have a POST function in my web service as below:
#POST
#Consumes({MediaType.APPLICATION_FORM_URLENCODED,MediaType.APPLICATION_JSON})
public Response showSearchResult(String incomingData) throws Exception {
String query = incomingData;
RepositoryMongo repository = new RepositoryMongo("InvertedIndex", "InvertedIndex", "documents");
InvertedIndex invertedIndex = new InvertedIndex(repository);
ArrayList<Posting> result = invertedIndex.processQuery_Posting_Based(query, 10,"1");
String htmlResult = invertedIndex.getHTMLResult(result);
return Response.ok(htmlResult).build();
}
The problem is that my incomingData = "query_input=canada+singer&search=search", while I want it to be the content of the textbox only. I can parse the string that I am receiving, but is that way correct? Is there any way that I can get "canada singer" as input directly? how can I control input type?
You can use the #FormParam annotation for a POST request, or the #PathParam annotation for a GET request. These go on parameters to your method, to indicate that the values for the parameters should be pulled out of either the URL (for a GET) or the posted body (for a POST).
Have a look at section 7.3 of http://www.vogella.com/tutorials/REST/article.html where there is a working example.
For this result - “query_input=canada+singer" ,you can get the url value with #QueryParam("query_input").
Alternatively,
We can even implement this using this #Context UriInfo
getQueryParameters() method has getFirst - in which you include the argument to fetch,just like below
String query_input_value= url.getQueryParameters().getFirst("query_input");
Try this :
#POST
#Consumes({MediaType.APPLICATION_FORM_URLENCODED,MediaType.APPLICATION_JSON})
public Response showSearchResult(#Context UriInfo url) throws Exception {
String query_input_value= url.getQueryParameters().getFirst("query_input");
String query = incomingData;
RepositoryMongo repository = new RepositoryMongo("InvertedIndex", "InvertedIndex", "documents");
InvertedIndex invertedIndex = new InvertedIndex(repository);
ArrayList<Posting> result = invertedIndex.processQuery_Posting_Based(query, 10,"1");
String htmlResult = invertedIndex.getHTMLResult(result);
return Response.ok(htmlResult).build();
}

Trying to use bing translator API with Robospice in Android

I need to implement robospice for doing the networking part in my Translator app. I previously used async task class and it was working fine, but now i want to improve my application with implementing robospice. I'am trying to execute the following code but it doesn't't throw any exception it just never executes....
#Override
public TranslatedText loadDataFromNetwork() throws Exception {
String jsonString = getJsonString();
String headerValue = getHeaderValue(jsonString);
String text = pair.getWordPairs().getWordFrom();
String languageFrom = pair.getLanguagePairs().getLanguageFrom().getCode();
String languageTo = pair.getLanguagePairs().getLangougateTo().getCode();
String uri = String
.format("http://api.microsofttranslator.com/v2/Http.svc/Translate?text=%s&from=%s&to=%s&contentType=text/html",
URLEncoder.encode(text, "UTF-8"),
URLEncoder.encode(languageFrom, "UTF-8"),
URLEncoder.encode(languageTo, "UTF-8"));
HttpHeaders headers = new HttpHeaders();
headers.set("Authorization", headerValue);
// Create a new RestTemplate instance
RestTemplate restTemplate = new RestTemplate();
// Add the Simple XML message converter
getRestTemplate().getMessageConverters().add(new SimpleXmlHttpMessageConverter());
//set the headerValue in the Entity
org.springframework.http.HttpEntity<?> request = new org.springframework.http.HttpEntity<Object>(headerValue);
// Make the HTTP GET request, marshaling the response from XML to an
// EventList
Log.v("request","Making request!");
//This line never finish execuitng, doesen't throw exception or anything in logCat
ResponseEntity<Object> responseEntity = getRestTemplate().exchange(uri, HttpMethod.GET, request, null);
Log.v("request", responseEntity.getBody().toString());
Log.d("Load Data From Network", request.getBody().toString());
return null;
}
The last thing it shows in log cat is Request First!! And nothing after that. It never even gets to The Request Listener onRequestFailure.
Can any 1 tell me what i do wrong ?
This is what look weird to me in your code:
ResponseEntity<Object> and null as 4th parameter of the exchange method are not correct. You need to provide a type which represents the response you get from the server.
The object returned by loadDataFromNetwork() is what you will get in the onRequestSuccess() method. Returning null is not a good idea, in my opinion.
I fixed the problem. So if you need to handle stream you will have to provide the following code
ResponseEntity<byte[]> responseEntity = getRestTemplate().exchange(uri, HttpMethod.GET, request, byte[]);

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