diff -r a467e8cbd16b -r 8c6885543e2c streamlet-examples/streamlet-common.h
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/streamlet-examples/streamlet-common.h Mon Jan 27 00:03:14 2020 +0100
@@ -0,0 +1,230 @@
+/**
+ * Relational pipes
+ * Copyright © 2020 František Kučera (Frantovo.cz, GlobalCode.info)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 3 of the License.
+ *
+ * This program is 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see .
+ */
+#pragma once
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#include "../src/StreamletMsg.h"
+
+/**
+ * Unlike the protocol and the message format,
+ * these helper classes and functions are not part of the public API.
+ * Thus when writing custom streamlets, it is better to copy this file
+ * and review its changes while upgrading to new upstream version.
+ */
+
+using S = relpipe::in::filesystem::StreamletMsg;
+
+class Streamlet {
+private:
+
+ class Message {
+ public:
+ int code;
+ std::vector parameters;
+
+ Message() {
+ }
+
+ Message(int code) : code(code) {
+ }
+
+ Message(int code, std::vector parameters) : code(code), parameters(parameters) {
+ }
+
+ Message(int code, std::wstring p1) : code(code), parameters({p1}) {
+ }
+
+ Message(int code, std::wstring p1, std::wstring p2) : code(code), parameters({p1, p2}) {
+ }
+ };
+
+ static const char SEPARATOR = '\0';
+
+ int readInt() {
+ return std::stoi(readString());
+ }
+
+ std::wstring readString() {
+ std::stringstream s;
+ for (char ch; std::cin.read(&ch, 1).good() && ch != SEPARATOR;) s.put(ch);
+ return convertor.from_bytes(s.str());
+ }
+
+ void writeString(std::wstring s) {
+ std::cout << convertor.to_bytes(s.c_str());
+ std::cout.put(SEPARATOR);
+ if (std::cout.bad()) throw std::runtime_error("Unable to write to sub-process.");
+ }
+
+ void writeInt(int i) {
+ writeString(std::to_wstring(i));
+ }
+
+ void flush() {
+ std::cout.flush();
+ }
+
+ Message read() {
+ Message m;
+ m.code = readInt();
+ int count = readInt();
+ for (int i = 0; i < count; i++) m.parameters.push_back(readString());
+ return m;
+ }
+
+ void processMessages() {
+ while (true) {
+ Message m = read();
+ if (m.code == S::VERSION_SUPPORTED) processVersionSupported(m);
+ else if (m.code == S::WAITING_FOR_VERSION) processWaitingForVersion(m);
+ else if (m.code == S::RELATION_START) processRelationStart(m);
+ else if (m.code == S::INPUT_ATTRIBUTE_METADATA) processInputAttributeMetadata(m);
+ else if (m.code == S::OUTPUT_ATTRIBUTE_ALIAS) processOutputAttributeAlias(m);
+ else if (m.code == S::OPTION) processOption(m);
+ else if (m.code == S::INPUT_ATTRIBUTE) processInputAttribute(m);
+ else if (m.code == S::WAITING_FOR_OUTPUT_ATTRIBUTES_METADATA) processWaitingForOutputAttributesMetadata(m);
+ else if (m.code == S::WAITING_FOR_OUTPUT_ATTRIBUTES) processWaitingForOutputAttributes(m);
+ else if (m.code == S::RELATION_END) break;
+ else processUnsupportedMessage(m);
+ }
+ }
+
+protected:
+
+ class AttributeMetadata {
+ public:
+ std::wstring name;
+ std::wstring type;
+ };
+
+ class OutputAttribute {
+ public:
+ std::wstring value;
+ bool isNull;
+ };
+
+ class Option {
+ public:
+ std::wstring name;
+ std::wstring value;
+ };
+
+ std::vector versionsSupported;
+ std::vector inputAttributes;
+ std::vector outputAttributeAliases;
+ std::vector