org.hcjf.io.net.http.RestContext Maven / Gradle / Ivy
package org.hcjf.io.net.http;
import com.google.gson.*;
import org.hcjf.encoding.MimeType;
import org.hcjf.errors.HCJFRuntimeException;
import org.hcjf.layers.Layers;
import org.hcjf.layers.crud.CreateLayerInterface;
import org.hcjf.layers.crud.DeleteLayerInterface;
import org.hcjf.layers.crud.ReadLayerInterface;
import org.hcjf.layers.crud.UpdateLayerInterface;
import org.hcjf.layers.query.*;
import org.hcjf.properties.SystemProperties;
import org.hcjf.utils.JsonUtils;
import org.hcjf.utils.Strings;
import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.util.*;
import java.util.regex.Pattern;
/**
* This class provides an abstraction to implements a simple rest end point that
* join any rest rule with some layer implementation.
* @author javaito
*/
public class RestContext extends Context {
private static class Fields {
private static final String VALUE_FIELD = "value";
private static final String PARAMS_FIELD = "params";
private static final String ID_URL_FIELD = "id";
private static final String REQUEST_CONFIG = "__request_config";
private static final String DATE_FORMAT_CONFIG = "dateFormat";
private static class Throwable {
private static final String MESSAGE = "message";
private static final String EXCEPTION = "exception";
private static final String BODY = "body";
private static final String TAGS = "tags";
}
}
private static final String REGEX_TEMPLATE = "\\/%s(\\/(?[A-Za-z0-9\\-\\_]{0,})){0,}";
private static final String DEFAULT_QUERY_PARAMETER = "q";
private final List idRegexList;
public RestContext(String baseContext) {
this(baseContext, List.of(SystemProperties.getPattern(SystemProperties.HCJF_UUID_REGEX)));
}
public RestContext(String baseContext, List idRegexList) {
super(String.format(REGEX_TEMPLATE, Strings.trim(baseContext, Strings.SLASH)));
this.idRegexList = idRegexList;
}
/**
* This method receive the http request and delegate each request for the different method depends of the
* http method and the request body.
* @param request All the request information.
* @return Returns the response object.
*/
@Override
public HttpResponse onContext(HttpRequest request) {
HttpMethod method = request.getMethod();
JsonParser jsonParser = new JsonParser();
Gson gson = new GsonBuilder().setDateFormat(SystemProperties.get(SystemProperties.HCJF_DEFAULT_DATE_FORMAT)).create();
JsonElement jsonElement;
Collection headers = new ArrayList<>();
String lastPart = request.getPathParts().get(request.getPathParts().size() -1);
Object id = null;
for(Pattern idRegex : idRegexList) {
if(idRegex.matcher(lastPart).matches()) {
id = Strings.deductInstance(lastPart);
break;
}
}
String resourceName = Strings.join(request.getPathParts().stream().skip(1).limit(request.getPathParts().size() -
(id == null ? 0 : 2)), Strings.CLASS_SEPARATOR);
if(method.equals(HttpMethod.GET)) {
if(id == null) {
if (request.hasParameter(DEFAULT_QUERY_PARAMETER)) {
Queryable queryable = Query.compile(request.getParameter(DEFAULT_QUERY_PARAMETER));
Collection queryResult = Query.evaluate(queryable);
if(queryResult instanceof ResultSet) {
ResultSet resultSet = (ResultSet) queryResult;
headers.add(new HttpHeader(HttpHeader.X_HCJF_QUERY_TOTAL_TIME, resultSet.getTotalTime().toString()));
headers.add(new HttpHeader(HttpHeader.X_HCJF_QUERY_TIME_COMPILING, resultSet.getTimeCompilingQuery().toString()));
headers.add(new HttpHeader(HttpHeader.X_HCJF_QUERY_TIME_COLLECTING_DATA, resultSet.getTimeCollectingData().toString()));
headers.add(new HttpHeader(HttpHeader.X_HCJF_QUERY_TIME_EVALUATING_CONDITIONS, resultSet.getTimeEvaluatingConditions().toString()));
headers.add(new HttpHeader(HttpHeader.X_HCJF_QUERY_AVERAGE_TIME_EVALUATING_CONDITIONS, resultSet.getAverageTimeFormattingDataByRow().toString()));
headers.add(new HttpHeader(HttpHeader.X_HCJF_QUERY_TIME_FORMATTING_DATA, resultSet.getTimeFormattingData().toString()));
headers.add(new HttpHeader(HttpHeader.X_HCJF_QUERY_AVERAGE_TIME_FORMATTING_DATA, resultSet.getAverageTimeFormattingDataByRow().toString()));
headers.add(new HttpHeader(HttpHeader.X_HCJF_QUERY_PRESENT_FIELDS, Strings.join(resultSet.getPresentFields(), Strings.ARGUMENT_SEPARATOR)));
}
jsonElement = gson.toJsonTree(queryResult);
} else {
ReadLayerInterface readLayerInterface = Layers.get(ReadLayerInterface.class, resourceName);
jsonElement = gson.toJsonTree(readLayerInterface.read());
}
} else {
ReadLayerInterface readLayerInterface = Layers.get(ReadLayerInterface.class, resourceName);
jsonElement = gson.toJsonTree(readLayerInterface.read(id));
}
} else if(method.equals(HttpMethod.POST)) {
RequestModel requestModel = new RequestModel((JsonObject) jsonParser.parse(new String(request.getBody())));
if(requestModel.getBody() == null) {
// If the method is post and the body object is null then the request attempt to create a parameterized
// query instance or a group of queryable instances.
if(requestModel.getQueryable() != null) {
jsonElement = gson.toJsonTree(Query.evaluate(requestModel.getQueryable()));
} else if(requestModel.getQueryables() != null){
JsonObject queriesResult = new JsonObject();
for(String key : requestModel.getQueryables().keySet()) {
try {
queriesResult.add(key, gson.toJsonTree(Query.evaluate(requestModel.getQueryables().get(key))));
} catch (Throwable throwable){
queriesResult.add(key, createJsonFromThrowable(throwable));
}
}
jsonElement = queriesResult;
} else {
throw new HCJFRuntimeException("Unsupported POST method configuration");
}
} else {
// This method call by default to create layer interface implementation.
CreateLayerInterface createLayerInterface = Layers.get(CreateLayerInterface.class, resourceName);
jsonElement = gson.toJsonTree(createLayerInterface.create(requestModel.getBody()));
}
} else if(method.equals(HttpMethod.PUT)) {
// This method call to update layer interface implementation.
UpdateLayerInterface updateLayerInterface = Layers.get(UpdateLayerInterface.class, resourceName);
RequestModel requestModel = new RequestModel((JsonObject) jsonParser.parse(new String(request.getBody())));
if(id != null) {
requestModel.getBody().put(Fields.ID_URL_FIELD, id);
jsonElement = gson.toJsonTree(updateLayerInterface.update(requestModel.getBody()));
} else {
jsonElement = gson.toJsonTree(updateLayerInterface.update(requestModel.queryable, requestModel.getBody()));
}
} else if(method.equals(HttpMethod.DELETE)) {
// This method call to delete layer interface implementation.
DeleteLayerInterface deleteLayerInterface = Layers.get(DeleteLayerInterface.class, resourceName);
if(id != null) {
jsonElement = gson.toJsonTree(deleteLayerInterface.delete(id));
} else {
RequestModel requestModel = new RequestModel((JsonObject) jsonParser.parse(new String(request.getBody())));
jsonElement = gson.toJsonTree(deleteLayerInterface.delete(requestModel.getQueryable()));
}
} else {
throw new HCJFRuntimeException("Unsupported http method: %s", method.toString());
}
HttpResponse response = new HttpResponse();
response.addHeader(new HttpHeader(HttpHeader.CONTENT_TYPE, MimeType.APPLICATION_JSON.toString()));
byte[] body = jsonElement.toString().getBytes();
response.addHeader(new HttpHeader(HttpHeader.CONTENT_LENGTH, Integer.toString(body.length)));
for(HttpHeader header : headers) {
response.addHeader(header);
}
response.setBody(body);
return response;
}
/**
* This method generate error response all the times that the request generates an throwable instance.
* @param request All the request information.
* @param throwable Throwable object, could be null.
* @return Returns http response instance.
*/
@Override
protected HttpResponse onError(HttpRequest request, Throwable throwable) {
HttpResponse response = new HttpResponse();
response.setResponseCode(HttpResponseCode.BAD_REQUEST);
response.addHeader(new HttpHeader(HttpHeader.CONTENT_TYPE, MimeType.APPLICATION_JSON.toString()));
byte[] body = createJsonFromThrowable(throwable).toString().getBytes();
response.addHeader(new HttpHeader(HttpHeader.CONTENT_LENGTH, Integer.toString(body.length)));
response.setBody(body);
return response;
}
/**
* This method create a json object from a throwable.
* @param throwable throwable instance.
* @return Json object.
*/
private JsonObject createJsonFromThrowable(Throwable throwable) {
JsonObject jsonObject = new JsonObject();
if(throwable.getMessage() != null) {
jsonObject.addProperty(Fields.Throwable.MESSAGE, throwable.getMessage());
}
Map tags = getTags(throwable, new HashMap<>());
if(!tags.isEmpty()) {
JsonObject jsonTags = new JsonObject();
for(String tag : tags.keySet()) {
jsonTags.addProperty(tag, tags.get(tag));
}
jsonObject.add(Fields.Throwable.TAGS, jsonTags);
}
jsonObject.addProperty(Fields.Throwable.EXCEPTION, throwable.getClass().getName());
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
PrintStream printStream = new PrintStream(byteArrayOutputStream);
throwable.printStackTrace(printStream);
jsonObject.addProperty(Fields.Throwable.BODY, byteArrayOutputStream.toString());
return jsonObject;
}
/**
* Find all the tags into the throwable instances and his causes.
* @param throwable Throwable instance.
* @param tag Map to store the tags founded.
* @return Return the same map sending as parameter.
*/
private Map getTags(Throwable throwable, Map tag) {
if(throwable.getMessage() != null) {
tag.putAll(Strings.getTagsFromMessage(throwable.getMessage()));
}
if(throwable.getCause() != null) {
tag = getTags(throwable.getCause(), tag);
}
return tag;
}
/**
* This inner class contains the necessary methods to parse the request body in order to call
* the specific layer implementation.
*/
private static class RequestModel {
private Map body;
private Queryable queryable;
private Map queryables;
private Map requestConfig;
public RequestModel(JsonObject jsonObject) {
if(!jsonObject.has(SystemProperties.get(SystemProperties.Net.Rest.BODY_FIELD)) &&
!jsonObject.has(SystemProperties.get(SystemProperties.Net.Rest.QUERY_FIELD)) &&
!jsonObject.has(SystemProperties.get(SystemProperties.Net.Rest.QUERIES_FIELD))) {
body = JsonUtils.createBody(jsonObject);
} else {
if (jsonObject.has(SystemProperties.get(SystemProperties.Net.Rest.BODY_FIELD))) {
body = JsonUtils.createBody(jsonObject.getAsJsonObject(SystemProperties.get(SystemProperties.Net.Rest.BODY_FIELD)));
}
if (jsonObject.has(SystemProperties.get(SystemProperties.Net.Rest.QUERY_FIELD))) {
queryable = createQuery(jsonObject.get(SystemProperties.get(SystemProperties.Net.Rest.QUERY_FIELD)));
}
if (jsonObject.has(SystemProperties.get(SystemProperties.Net.Rest.QUERIES_FIELD))) {
queryables = new HashMap<>();
JsonObject queryablesObject = jsonObject.getAsJsonObject(SystemProperties.get(SystemProperties.Net.Rest.QUERIES_FIELD));
for (String key : queryablesObject.keySet()) {
queryables.put(key, createQuery(queryablesObject.get(key)));
}
}
}
}
/**
* Creates the queryable instance from a json element.
* @param element Json element instance.
* @return Returns the queriable instance.
*/
private Queryable createQuery(JsonElement element) {
Queryable result;
if(element instanceof JsonObject) {
JsonObject queryJsonObject = element.getAsJsonObject();
ParameterizedQuery parameterizedQuery = Query.compile(queryJsonObject.get(Fields.VALUE_FIELD).getAsString()).getParameterizedQuery();
if(queryJsonObject.has(Fields.PARAMS_FIELD)) {
for (Object parameter : JsonUtils.createList(queryJsonObject.get(Fields.PARAMS_FIELD).getAsJsonArray())) {
parameterizedQuery.add(parameter);
}
}
result = parameterizedQuery;
} else {
result = Query.compile(element.getAsString());
}
return result;
}
/**
* Returns the body of the request.
* @return Body of the request.
*/
public Map getBody() {
return body;
}
/**
* Returns the queryable instance of the request.
* @return Queriable instace.
*/
public Queryable getQueryable() {
return queryable;
}
/**
* Returns a map of the queryable instances of the request.
* @return Queryable instances of the request.
*/
public Map getQueryables() {
return queryables;
}
}
}
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