Java tutorial
/* * Copyright 2015 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.cloud.dataflow.shell.command; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStreamReader; import java.net.URI; import java.nio.charset.Charset; import java.util.Collections; import java.util.HashMap; import com.fasterxml.jackson.core.JsonFactory; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.ObjectMapper; import org.springframework.http.HttpEntity; import org.springframework.http.HttpHeaders; import org.springframework.http.HttpStatus; import org.springframework.http.MediaType; import org.springframework.http.ResponseEntity; import org.springframework.http.client.ClientHttpResponse; import org.springframework.shell.core.CommandMarker; import org.springframework.shell.core.annotation.CliCommand; import org.springframework.shell.core.annotation.CliOption; import org.springframework.shell.support.util.OsUtils; import org.springframework.stereotype.Component; import org.springframework.util.Assert; import org.springframework.util.FileCopyUtils; import org.springframework.web.client.ResourceAccessException; import org.springframework.web.client.ResponseErrorHandler; import org.springframework.web.client.RestTemplate; /** * Http commands. * * @author Jon Brisbin * @author Ilayaperumal Gopinathan * @author Gunnar Hillert * @author Eric Bottard * @author David Turanski */ @Component public class HttpCommands implements CommandMarker { private static final String DEFAULT_MEDIA_TYPE = MediaType.TEXT_PLAIN_VALUE + "; Charset=UTF-8"; private static final String POST_HTTPSOURCE = "http post"; private static final String GET_HTTPSOURCE = "http get"; @CliCommand(value = { POST_HTTPSOURCE }, help = "POST data to http endpoint") public String postHttp(@CliOption(mandatory = false, key = { "", "target" }, help = "the location to post to", unspecifiedDefaultValue = "http://localhost:9000") String target, @CliOption(mandatory = false, key = "data", help = "the text payload to post. exclusive with file. embedded double quotes are not supported if next to a space character") String data, @CliOption(mandatory = false, key = "file", help = "filename to read data from. exclusive with data") File file, @CliOption(mandatory = false, key = "contentType", help = "the content-type to use. file is also read using the specified charset", unspecifiedDefaultValue = DEFAULT_MEDIA_TYPE) MediaType mediaType) throws IOException { Assert.isTrue(file != null || data != null, "One of 'file' or 'data' must be set"); Assert.isTrue(file == null || data == null, "Only one of 'file' or 'data' must be set"); if (mediaType.getCharSet() == null) { mediaType = new MediaType(mediaType, Collections.singletonMap("charset", Charset.defaultCharset().toString())); } if (file != null) { InputStreamReader isr = new InputStreamReader(new FileInputStream(file), mediaType.getCharSet()); data = FileCopyUtils.copyToString(isr); } final StringBuilder buffer = new StringBuilder(); URI requestURI = URI.create(target); final HttpHeaders headers = new HttpHeaders(); headers.setContentType(mediaType); final HttpEntity<String> request = new HttpEntity<String>(data, headers); try { outputRequest("POST", requestURI, mediaType, data, buffer); ResponseEntity<String> response = createRestTemplate(buffer).postForEntity(requestURI, request, String.class); outputResponse(response, buffer); if (!response.getStatusCode().is2xxSuccessful()) { buffer.append(OsUtils.LINE_SEPARATOR) .append(String.format("Error sending data '%s' to '%s'", data, target)); } return buffer.toString(); } catch (ResourceAccessException e) { return String.format(buffer.toString() + "Failed to access http endpoint %s", target); } catch (Exception e) { return String.format(buffer.toString() + "Failed to send data to http endpoint %s", target); } } @CliCommand(value = { GET_HTTPSOURCE }, help = "Make GET request to http endpoint") public String getHttp(@CliOption(mandatory = false, key = { "", "target" }, help = "the URL to make the request to", unspecifiedDefaultValue = "http://localhost:9393") String target) throws IOException { final StringBuilder buffer = new StringBuilder(); URI requestURI = URI.create(target); try { outputRequest("GET", requestURI, null, "", buffer); ResponseEntity<String> response = createRestTemplate(buffer).getForEntity(requestURI, String.class); outputResponse(response, buffer); if (!response.getStatusCode().is2xxSuccessful()) { buffer.append(OsUtils.LINE_SEPARATOR) .append(String.format("Error sending request to '%s'", target)); } return buffer.toString(); } catch (ResourceAccessException e) { return String.format(buffer.toString() + "Failed to access http endpoint %s", target); } catch (Exception e) { return String.format(buffer.toString() + "Failed to get data from http endpoint %s", target); } } private RestTemplate createRestTemplate(final StringBuilder buffer) { RestTemplate restTemplate = new RestTemplate(); restTemplate.setErrorHandler(new ResponseErrorHandler() { @Override public boolean hasError(ClientHttpResponse response) throws IOException { HttpStatus status = response.getStatusCode(); return (status == HttpStatus.BAD_GATEWAY || status == HttpStatus.GATEWAY_TIMEOUT || status == HttpStatus.INTERNAL_SERVER_ERROR); } @Override public void handleError(ClientHttpResponse response) throws IOException { outputError(response.getStatusCode(), buffer); } }); return restTemplate; } private void outputRequest(String method, URI requestUri, MediaType mediaType, String requestData, StringBuilder buffer) { buffer.append("> ").append(method).append(' '); if (mediaType != null) { buffer.append("(").append(mediaType.toString()).append(") "); } buffer.append(requestUri.toString()).append(" ").append(requestData).append(OsUtils.LINE_SEPARATOR); } private void outputResponse(ResponseEntity<String> response, StringBuilder buffer) { buffer.append("> ").append(response.getStatusCode().value()).append(" ") .append(response.getStatusCode().name()).append(OsUtils.LINE_SEPARATOR); String maybeJson = response.getBody(); if (maybeJson != null) { buffer.append(prettyPrintIfJson(maybeJson)); } } private String prettyPrintIfJson(String maybeJson) { JsonFactory factory = new JsonFactory(); ObjectMapper mapper = new ObjectMapper(factory); TypeReference<HashMap<String, Object>> typeRef = new TypeReference<HashMap<String, Object>>() { }; try { return mapper.writerWithDefaultPrettyPrinter().writeValueAsString(mapper.readValue(maybeJson, typeRef)); } catch (IOException e) { // Not JSON? Return unchanged return maybeJson; } } private void outputError(HttpStatus status, StringBuilder buffer) { buffer.append("> ").append(status.value()).append(" ").append(status.name()).append(OsUtils.LINE_SEPARATOR); } }