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PlantUML is a component that allows to quickly write diagrams from text.
// THIS FILE HAS BEEN GENERATED BY A PREPROCESSOR.
/* +=======================================================================
* |
* | PlantUML : a free UML diagram generator
* |
* +=======================================================================
*
* (C) Copyright 2009-2024, Arnaud Roques
*
* Project Info: https://plantuml.com
*
* If you like this project or if you find it useful, you can support us at:
*
* https://plantuml.com/patreon (only 1$ per month!)
* https://plantuml.com/liberapay (only 1€ per month!)
* https://plantuml.com/paypal
*
*
* PlantUML is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* PlantUML distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library. If not, see
* Supports three parameters for datasource, default JSON value and charset. The
* datasource will be checked against the security rules.
*
* Examples:
*
*
* @ startuml
* ' loads a local file
* !$JSON_LOCAL_RELATIVE=%load_json("file.json")
*
* ' loads a local file from an absolute file path
* !$JSON_LOCAL_ABS=%load_json("c:/loaded/data/file.json")
*
* ' tries to load a local file and returns an empty JSON
* !$JSON_LOCAL_REL_EMPTY=%load_json("file-not-existing.json")
*
* ' tries to load a local file and returns an default JSON
* !$DEF_JSON={"status":"No data found"}
* !$JSON_LOCAL_REL_DEF=%load_json("file-not-existing.json", $DEF_JSON)
*
* ' loads a local file with a specific charset (default is UTF-8)
* !$JSON_LOCAL_RELATIVE_CHARSET=%load_json("file.json", "{}", "iso-8859-1")
*
* ' loads a remote JSON from an endpoint (and default, if not reachable)
* !$STATUS_NO_CONNECTION={"status": "No connection"}
* !$JSON_REMOTE_DEF=%load_json("https://localhost:7778/management/health", $STATUS_NO_CONNECTION)
* status -> $JSON_REMOTE_DEF.status
* @ enduml
*
*
* @author Aljoscha Rittner
*/
public class LoadJson extends SimpleReturnFunction {
private static final String VALUE_CHARSET_DEFAULT = "UTF-8";
private static final String VALUE_DEFAULT_DEFAULT = "{}";
public TFunctionSignature getSignature() {
return new TFunctionSignature("%load_json", 3);
}
@Override
public boolean canCover(int nbArg, Set namedArgument) {
return nbArg == 1 || nbArg == 2 || nbArg == 3;
}
@Override
public TValue executeReturnFunction(TContext context, TMemory memory, StringLocated location, List values,
Map named) throws EaterException {
final String path = values.get(0).toString();
try {
String data = loadStringData(path, getCharset(values));
if (data == null)
data = getDefaultJson(values);
JsonValue jsonValue = Json.parse(data);
return TValue.fromJson(jsonValue);
} catch (ParseException pe) {
Logme.error(pe);
throw new EaterException("JSON parse issue in source " + path + " on location " + pe.getLocation(), location);
} catch (UnsupportedEncodingException e) {
Logme.error(e);
throw new EaterException("JSON encoding issue in source " + path + ": " + e.getMessage(), location);
}
}
/**
* Returns the JSON default, if the data source contains no data.
*
* @param values value parameters
* @return the defined default JSON or {@code "{}"}
*/
private String getDefaultJson(List values) {
if (values.size() > 1)
return values.get(1).toString();
return VALUE_DEFAULT_DEFAULT;
}
/**
* Returns the charset name (if set)
*
* @param values value parameters
* @return defined charset or {@code "UTF-8"}
*/
private String getCharset(List values) {
if (values.size() == 3)
return values.get(2).toString();
return VALUE_CHARSET_DEFAULT;
}
/**
* Loads String data from a data source {@code path} (file or URL) and expects
* the data encoded in {@code charset}.
*
* @param path path to data source (http(s)-URL or file).
* @param charset character set to encode the string data
* @return the decoded String from the data source
* @throws EaterException if something went wrong on reading data
*/
private String loadStringData(String path, String charset)
throws EaterException, UnsupportedEncodingException {
byte[] byteData = null;
if (path.startsWith("http://") || path.startsWith("https://")) {
final SURL url = SURL.create(path);
if (url != null)
byteData = url.getBytes();
// ::comment when __CORE__
} else {
try {
final SFile file = FileSystem.getInstance().getFile(path);
if (file != null && file.exists() && file.canRead() && !file.isDirectory()) {
final ByteArrayOutputStream out = new ByteArrayOutputStream(1024 * 8);
FileUtils.copyToStream(file, out);
byteData = out.toByteArray();
}
} catch (IOException e) {
Logme.error(e);
}
}
if (byteData == null || byteData.length == 0)
return null; // no length, no data (we want the default)
return new String(byteData, charset);
}
}