RestTemplate: How to send URL and query parameters

问题:

I am trying to pass path param and query params in a URL but I am getting a weird error. below is the code

    String url = "http://test.com/Services/rest/{id}/Identifier"
    Map<String, String> params = new HashMap<String, String>();
    params.put("id", "1234");
    UriComponentsBuilder builder = UriComponentsBuilder.fromUriString(url)
                                        .queryParam("name", "myName");
    String uriBuilder = builder.build().encode().toUriString();
    restTemplate.exchange(uriBuilder , HttpMethod.PUT, requestEntity,
                    class_p, params);

and my url is becoming http://test.com/Services/rest/%7Bid%7D/Identifier?name=myName

what should I do to make it work. I am expecting http://test.com/Services/rest/{id}/Identifier?name=myName so that params will add id to the url

please suggest. thanks in Advance

回答1:

I would use buildAndExpand from UriComponentsBuilder to pass all types of URI parameters.

For example:

String url = "http://test.com/solarSystem/planets/{planet}/moons/{moon}";

// URI (URL) parameters
Map<String, String> urlParams = new HashMap<>();
urlParams.put("planets", "Mars");
urlParams.put("moons", "Phobos");

// Query parameters
UriComponentsBuilder builder = UriComponentsBuilder.fromUriString(url)
        // Add query parameter
        .queryParam("firstName", "Mark")
        .queryParam("lastName", "Watney");

System.out.println(builder.buildAndExpand(urlParams).toUri());
/**
 * Console output:
 * http://test.com/solarSystem/planets/Mars/moons/Phobos?firstName=Mark&lastName=Watney
 */

restTemplate.exchange(builder.buildAndExpand(urlParams).toUri() , HttpMethod.PUT,
        requestEntity, class_p);

/**
 * Log entry:
 * org.springframework.web.client.RestTemplate Created PUT request for "http://test.com/solarSystem/planets/Mars/moons/Phobos?firstName=Mark&lastName=Watney"
 */

回答2:

An issue with the answer from Michal Foksa is that it adds the query parameters first, and then expands the path variables. If query parameter contains parenthesis, e.g. {foobar}, this will cause an exception.

The safe way is to expand the path variables first, and then add the query parameters:

String url = "http://test.com/Services/rest/{id}/Identifier";
Map<String, String> params = new HashMap<String, String>();
params.put("id", "1234");
URI uri = UriComponentsBuilder.fromUriString(url)
        .buildAndExpand(params)
        .toUri();
uri = UriComponentsBuilder
        .fromUri(uri)
        .queryParam("name", "myName")
        .build()
        .toUri();
restTemplate.exchange(uri , HttpMethod.PUT, requestEntity, class_p);

回答3:

One-liner using TestRestTemplate.exchange function with parameters map.

restTemplate.exchange("/someUrl?id={id}", HttpMethod.GET, reqEntity, respType, ["id": id])

The params map initialized like this is a groovy initializer*