/**
* 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);
}
}
/**
* Sends a POST request with a file and returns the response.
*
* @param endpoint The endpoint to send the request to.
* @param file The file to upload
* @param responseClass The class to deserialise the Json response to. Can be null if no response
* message is expected.
* @param <T> The type to deserialise the response to.
* @return A {@link Response} containing the deserialised body, if any.
* @throws IOException If an error occurs.
* @see MultipartEntityBuilder
*/
private <T> Response<T> post(Endpoint endpoint, File file, Class<T> responseClass)
throws IOException {
if (file == null) {
return post(endpoint, responseClass);
} // deal with null case
// Create the request
HttpPost post = new HttpPost(endpoint.url());
post.setHeaders(combineHeaders());
// Add fields as text pairs
MultipartEntityBuilder multipartEntityBuilder = MultipartEntityBuilder.create();
// Add file as binary
FileBody fileBody = new FileBody(file);
multipartEntityBuilder.addPart("file", fileBody);
// Set the body
post.setEntity(multipartEntityBuilder.build());
// Send the request and process the response
try (CloseableHttpResponse response = httpClient().execute(post)) {
if (String.class.isAssignableFrom(responseClass)) {
String body = getResponseString(response);
return new Response(response.getStatusLine(), body);
} else {
T body = deserialiseResponseMessage(response, responseClass);
return new Response<>(response.getStatusLine(), body);
}
}
}
/**
* Sends a POST request with a file and returns the response.
*
* @param endpoint The endpoint to send the request to.
* @param file The file to upload
* @param responseClass The class to deserialise the Json response to. Can be null if no response
* message is expected.
* @param fields Any name-value pairs to serialise
* @param <T> The type to deserialise the response to.
* @return A {@link Response} containing the deserialised body, if any.
* @throws IOException If an error occurs.
* @see MultipartEntityBuilder
*/
public <T> Response<T> post(
Endpoint endpoint, File file, Class<T> responseClass, NameValuePair... fields)
throws IOException {
if (file == null) {
return post(endpoint, responseClass, fields);
} // deal with null case
// Create the request
HttpPost post = new HttpPost(endpoint.url());
post.setHeaders(combineHeaders());
// Add fields as text pairs
MultipartEntityBuilder multipartEntityBuilder = MultipartEntityBuilder.create();
for (NameValuePair field : fields) {
multipartEntityBuilder.addTextBody(field.getName(), field.getValue());
}
// Add file as binary
FileBody bin = new FileBody(file);
multipartEntityBuilder.addPart("file", bin);
// Set the body
post.setEntity(multipartEntityBuilder.build());
// Send the request and process the response
try (CloseableHttpResponse response = httpClient().execute(post)) {
T body = deserialiseResponseMessage(response, responseClass);
return new Response<>(response.getStatusLine(), body);
}
}
/**
* Sends a POST request and returns the response.
*
* @param endpoint The endpoint to send the request to.
* @param responseClass The class to deserialise the Json response to. Can be null if no response
* message is expected.
* @param headers Any additional headers to send with this request. You can use {@link
* org.apache.http.HttpHeaders} constants for header names.
* @param <T> The type to deserialise the response to.
* @return A {@link Response} containing the deserialised body, if any.
* @throws IOException If an error occurs.
*/
public <T> Response<T> delete(Endpoint endpoint, Class<T> responseClass, NameValuePair... headers)
throws IOException {
// Create the request
HttpDelete delete = new HttpDelete(endpoint.url());
delete.setHeaders(combineHeaders(headers));
// Send the request and process the response
try (CloseableHttpResponse response = httpClient().execute(delete)) {
T body = deserialiseResponseMessage(response, responseClass);
return new Response<>(response.getStatusLine(), body);
}
}
/**
* Sends a GET request and returns the response.
*
* @param endpoint The endpoint to send the request to.
* @param responseClass The class to deserialise the Json response to. Can be null if no response
* message is expected.
* @param headers Any additional headers to send with this request. You can use {@link
* org.apache.http.HttpHeaders} constants for header names.
* @param <T> The type to deserialise the response to.
* @return A {@link Response} containing the deserialised body, if any.
* @throws IOException If an error occurs.
*/
public <T> Response<T> get(Endpoint endpoint, Class<T> responseClass, NameValuePair... headers)
throws IOException {
// Create the request
HttpGet get = new HttpGet(endpoint.url());
get.setHeaders(combineHeaders(headers));
// Send the request and process the response
try (CloseableHttpResponse response = httpClient().execute(get)) {
// System.out.println(response);
T body = deserialiseResponseMessage(response, responseClass);
return new Response<>(response.getStatusLine(), body);
}
}
/**
* Sends a POST request and returns the response.
*
* <p>Specifically for the use case where we have no requestMessage
*
* @param endpoint The endpoint to send the request to.
* @param responseClass The class to deserialise the Json response to. Can be null if no response
* message is expected.
* @param headers Any additional headers to send with this request. You can use {@link
* org.apache.http.HttpHeaders} constants for header names.
* @param <T> The type to deserialise the response to.
* @return A {@link Response} containing the deserialised body, if any.
* @throws IOException If an error occurs.
*/
public <T> Response<T> post(Endpoint endpoint, Class<T> responseClass, NameValuePair... headers)
throws IOException {
// Create the request
HttpPost post = new HttpPost(endpoint.url());
post.setHeaders(combineHeaders(headers));
// Add the request message if there is one
post.setEntity(serialiseRequestMessage(null));
// Send the request and process the response
try (CloseableHttpResponse response = httpClient().execute(post)) {
T body = deserialiseResponseMessage(response, responseClass);
return new Response<>(response.getStatusLine(), body);
}
}
/**
* 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;
}