Add license

RESTful version of simple socket listener.

LICENSE.txt

@@ -0,0 +1,7 @@
+Copyright 2024 Fabian Müller <fabian@fablab-altmuehlfranken.de>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

src/main.cpp

@@ -4,9 +4,11 @@
 
 #include "credentials.h"
 #include "webserver.h"
+#include "socketserver.h"
 #include "util.h"
 
 static ESP8266WiFiMulti wifiMulti;
+static SocketServer socketServer;
 
 void setup() {
     // serial console, for use via USB (also exposed to TXD0/RXD0 GPIOs)
@@ -43,10 +45,12 @@ void setup() {
     // configure HTTP endpoints
     configureWebServer();
 
-    // don't forget to start the webserver!
+    // don't forget to start all the services
     webServer.begin();
+    socketServer.begin();
 }
 
 void loop() {
     webServer.handleClient();
+    socketServer.handleClient();
 }

src/socketserver.h

@@ -0,0 +1,34 @@
+#pragma once
+
+class SocketServer {
+public:
+    static constexpr int Port = 3000;
+
+    void begin() {
+        _server.begin();
+    }
+
+    void handleClient() {
+        auto client = _server.available();
+
+        if (client) {
+            Serial.println("Client connected to socket server: " + client.remoteIP().toString() + ":" + client.remotePort());
+        } else {
+            return;
+        }
+
+        while (client.connected()) {
+            while (client.available() > 0) {
+                auto chr = client.read();
+                Serial.write(chr);
+                Serial1.write(chr);
+            }
+        }
+        client.stop();
+        Serial.println();
+        Serial.println("Client disconnected");
+    }
+
+private:
+    WiFiServer _server{Port};
+};

src/util.h

@@ -60,6 +60,7 @@ enum class Macros {
     Beep1 = 'q',
     Beep2 = 'r',
     Beep3 = 's',
+    Temperature = 'H',
 };
 
 // symbols should be inserted as string representations of their numeric value prefixed by ^
@@ -121,7 +122,7 @@ enum class ExtendedChar {
     LatinSmallLetterAWithCircumflex = 0x83,
     // ä
     LatinSmallLetterAWithDiaeresis = 0x84,
-    // á
+    // à
     LatinSmallLetterAWithGrave = 0x85,
     // å
     LatinSmallLetterAWithRingAbove = 0x86,
@@ -245,6 +246,19 @@ enum class ExtendedChar {
     GreekSmallLetterPhi = 0xed,
 };
 
+String hexDump(String in) {
+    String out;
+    for (size_t i = 0; i < in.length(); ++i) {
+        auto hexChar = String(in[i], HEX);
+        if (hexChar.length() == 1) {
+            out.concat('0');
+        }
+        out.concat(hexChar);
+        out.concat(' ');
+    }
+    return out;
+}
+
 /*
  * Message syntax:
  * separator: ~
@@ -298,13 +312,5 @@ void sendTextToSign(
     Serial1.print(toSend);
 
     Serial.println("Text sent to device: " + toSend);
-    Serial.print("Hex dump: ");
-    for (size_t i = 0; i < toSend.length(); ++i) {
-        auto hexChar = String(toSend[i], HEX);
-        if (hexChar.length() == 1) {
-            hexChar = '0' + hexChar;
-        }
-        Serial.print(hexChar + ' ');
-    }
-    Serial.println();
+    Serial.println("Hex dump: " + hexDump(toSend));
 }

src/webserver.h

@@ -66,6 +66,21 @@ namespace {
         sendTextToSign(text);
         webServer.send(200, "text/plain", "ok");
     }
+
+    // RESTful API endpoint -- returns a proper status code rather than a redirect
+    void handleRawApiSend() {
+        String toSend = webServer.arg("plain");
+
+        if (toSend.isEmpty()) {
+            webServer.send(404, "text/plain", "empty body");
+            return;
+        }
+
+        Serial.println("Raw message sent to device: " + toSend);
+        Serial.println("Hex dump: " + hexDump(toSend));
+        Serial1.print(toSend);
+        webServer.send(200, "text/plain", "ok");
+    }
 }
 
 void configureWebServer() {
@@ -74,4 +89,5 @@ void configureWebServer() {
     webServer.on("/", HTTPMethod::HTTP_GET, handleIndex);
     webServer.on("/", HTTPMethod::HTTP_POST, handleFormSend);
     webServer.on("/send", HTTPMethod::HTTP_POST, handleApiSend);
+    webServer.on("/raw", HTTPMethod::HTTP_POST, handleRawApiSend);
 }