/**
* Sends a GET request and returns the response.
*
* @param endpoint The endpoint to send the request to.
* @param headers Any additional headers to send with this request. You can use {@link
* org.apache.http.HttpHeaders} constants for header names.
* @return A {@link Path} to the downloaded content, if any.
* @throws IOException If an error occurs.
* @see java.nio.file.Files#probeContentType(Path)
*/
public Response<Path> get(Endpoint endpoint, NameValuePair... headers) throws IOException {
// Create the request
HttpGet get = new HttpGet(endpoint.url());
get.setHeaders(combineHeaders(headers));
Path tempFile = null;
// Send the request and process the response
try (CloseableHttpResponse response = httpClient().execute(get)) {
if (response.getStatusLine().getStatusCode() != HttpStatus.OK_200) {
return null;
} // If bad response return null
// Request the content
HttpEntity entity = response.getEntity();
// Download the content to a temporary file
if (entity != null) {
tempFile = Files.createTempFile("download", "file");
try (InputStream input = entity.getContent();
OutputStream output = Files.newOutputStream(tempFile)) {
IOUtils.copy(input, output);
}
}
return new Response<>(response.getStatusLine(), tempFile);
}
}
/**
* Deserialises the given {@link CloseableHttpResponse} to the specified type.
*
* @param response The response.
* @return The response as a String, or null if the response does not contain an entity.
* @throws IOException If an error occurs.
*/
private String getResponseString(CloseableHttpResponse response) throws IOException {
String body = null;
HttpEntity entity = response.getEntity();
if (entity != null) {
try (InputStream inputStream = entity.getContent()) {
body = IOUtils.toString(inputStream);
}
} else {
EntityUtils.consume(entity);
}
return body;
}
/**
* Deserialises the given {@link CloseableHttpResponse} to the specified type.
*
* @param response The response.
* @param responseClass The type to deserialise to.
* @param <T> The type to deserialise to.
* @return The deserialised response, or null if the response does not contain an entity.
* @throws IOException If an error occurs.
*/
private <T> T deserialiseResponseMessage(CloseableHttpResponse response, Class<T> responseClass)
throws IOException {
T body = null;
HttpEntity entity = response.getEntity();
if (entity != null) {
try (InputStream inputStream = entity.getContent()) {
try {
body = Serialiser.deserialise(inputStream, responseClass);
} catch (JsonSyntaxException e) {
// This can happen if an error HTTP code is received and the
// body of the response doesn't contain the expected object:
body = null;
}
}
} else {
EntityUtils.consume(entity);
}
return body;
}