Add ESP32 output driver, and some convience defines to allow using the same example code on all platforms.

Author: tfry-git

EmbAJAX.cpp

@@ -2,7 +2,7 @@
  * 
  * EmbAJAX - Simplistic framework for creating and handling displays and controls on a WebPage served by an Arduino (or other small device).
  * 
- * Copyright (C) 2018 Thomas Friedrichsmeier
+ * Copyright (C) 2018-2019 Thomas Friedrichsmeier
  * 
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published
@@ -19,6 +19,9 @@
  * 
 **/
 
+// Avoid auto-including an output driver, here.
+#define EMBAJAX_OUTUPUTDRIVER_IMPLEMENTATION
+
 #include "EmbAJAX.h"
 
 #define ITOA_BUFLEN 8

EmbAJAX.h

@@ -2,7 +2,7 @@
  * 
  * EmbAJAX - Simplistic framework for creating and handling displays and controls on a WebPage served by an Arduino (or other small device).
  * 
- * Copyright (C) 2018 Thomas Friedrichsmeier
+ * Copyright (C) 2018-2019 Thomas Friedrichsmeier
  * 
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published
@@ -18,8 +18,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  * 
 **/
-#ifndef ARDUJAX_H
-#define ARDUJAX_H
+#ifndef EMBAJAX_H
+#define EMBAJAX_H
 
 #include <Arduino.h>
 
@@ -163,34 +163,15 @@ class EmbAJAXOutputDriverBase {
     uint16_t next_revision;
 };
 
-#if defined (ESP8266)  // TODO: Move this to extra header
-#include <ESP8266WebServer.h>
-/**  @brief Output driver implementation for ESP8266WebServer */
-class EmbAJAXOutputDriverESP8266 : public EmbAJAXOutputDriverBase {
-public:
-    /** To register an ESP8266WebServer with EmbAJAX, simply create a (globaL) instance of this class. */
-    EmbAJAXOutputDriverESP8266(ESP8266WebServer *server) {
-        EmbAJAXBase::setDriver(this);
-        _server = server;
-    }
-    void printHeader(bool html) override {
-        _server->setContentLength(CONTENT_LENGTH_UNKNOWN);
-        if (html) {
-            _server->send(200, "text/html", "");
-        } else {
-            _server->send(200, "text/json", "");
-        }
-    }
-    void printContent(const char *content) override {
-        if (content[0] != '\0') _server->sendContent(content);  // NOTE: There seems to be a bug in the server when sending empty string.
-    }
-    const char* getArg(const char* name, char* buf, int buflen) override {
-        _server->arg(name).toCharArray (buf, buflen);
-        return buf;
-    };
-private:
-    ESP8266WebServer *_server;
-};
+// If the user has not #includ'ed a specific output driver implementation, make a good guess, here
+#if not defined (EMBAJAX_OUTUPUTDRIVER_IMPLEMENTATION)
+#if defined (ESP8266)
+#include <EmbAJAXOutputDriverESP8266.h>
+#elif defined (ESP32)
+#include <EmbAJAXOutputDriverESP32.h>
+#else
+#error No output driver available for this hardware (yet). Please implement your own (it is easy!) and submit a patch.
+#endif
 #endif
 
 /** Convenience macro to set up an EmbAJAXPage, without counting the number of elements for the template. See EmbAJAXPage::EmbAJAXPage()

EmbAJAXOutputDriverESP32.h

@@ -0,0 +1,33 @@
+/**
+ * 
+ * EmbAJAX - Simplistic framework for creating and handling displays and controls on a WebPage served by an Arduino (or other small device).
+ * 
+ * Copyright (C) 2018-2019 Thomas Friedrichsmeier
+ * 
+ * This program 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.
+ * 
+ * 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 Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+**/
+
+#ifndef EMBAJAXOUTPUTDRIVERESP32_H
+#define EMBAJAXOUTPUTDRIVERESP32_H
+
+#include <WebServer.h>
+#define EmbAJAXOutputDriverWebserverClass Webserver
+
+#include <WiFi.h>  // Makes the examples work cross-platform; not strictly needed
+
+// the actual implementation
+#include "EmbAJAXOutputDriverGeneric.h"
+
+#endif

EmbAJAXOutputDriverESP8266.h

@@ -0,0 +1,35 @@
+/**
+ * 
+ * EmbAJAX - Simplistic framework for creating and handling displays and controls on a WebPage served by an Arduino (or other small device).
+ * 
+ * Copyright (C) 2018-2019 Thomas Friedrichsmeier
+ * 
+ * This program 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.
+ * 
+ * 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 Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+**/
+
+#ifndef EMBAJAXOUTPUTDRIVERESP8266_H
+#define EMBAJAXOUTPUTDRIVERESP8266_H
+
+#include <ESP8266WebServer.h>
+#define EmbAJAXOutputDriverWebServerClass ESP8266WebServer
+#include <ESP8266WiFi.h>  // Makes the examples work cross-platform; not strictly needed
+
+// the actual implementation
+#include "EmbAJAXOutputDriverGeneric.h"
+
+// for compatibility with early code examples
+#define EmbAJAXOutputDriverESP8266 EmbAJAXOutputDriver
+
+#endif

EmbAJAXOutputDriverGeneric.h

@@ -0,0 +1,62 @@
+/**
+ * 
+ * EmbAJAX - Simplistic framework for creating and handling displays and controls on a WebPage served by an Arduino (or other small device).
+ * 
+ * Copyright (C) 2018-2019 Thomas Friedrichsmeier
+ * 
+ * This program 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.
+ * 
+ * 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 Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+**/
+
+#ifndef EMBAJAXOUTPUTDRIVERGENERIC_H
+#define EMBAJAXOUTPUTDRIVERGENERIC_H
+
+#if defined (EMBAJAX_OUTUPUTDRIVER_IMPLEMENTATION)
+#error Duplicate definition of output driver. Fix your include-directives.
+#endif
+#define EMBAJAX_OUTUPUTDRIVER_IMPLEMENTATION
+
+#if not defined EmbAJAXOutputDriverWebServerClass
+#error Please define EmbAJAXOutputDriverWebServerClass or #include appropriate hardware specific driver
+#endif
+
+/**  @brief Output driver implementation. This implementation should work for most arduino web servers with minimal adjustmnets. */
+class EmbAJAXOutputDriver : public EmbAJAXOutputDriverBase {
+public:
+    /** To register an WebServer with EmbAJAX, simply create a (globaL) instance of this class. 
+        @param server pointer to the server. The class of this is usually an auto-detected sensible default for the platform, e.g. ESP8266WebServer on ESP8266. */
+    EmbAJAXOutputDriver(EmbAJAXOutputDriverWebServerClass *server) {
+        EmbAJAXBase::setDriver(this);
+        _server = server;
+    }
+    void printHeader(bool html) override {
+        _server->setContentLength(CONTENT_LENGTH_UNKNOWN);
+        if (html) {
+            _server->send(200, "text/html", "");
+        } else {
+            _server->send(200, "text/json", "");
+        }
+    }
+    void printContent(const char *content) override {
+        if (content[0] != '\0') _server->sendContent(content);  // NOTE: There seems to be a bug in the ESP8266 server when sending empty string.
+    }
+    const char* getArg(const char* name, char* buf, int buflen) override {
+        _server->arg(name).toCharArray (buf, buflen);
+        return buf;
+    };
+private:
+    EmbAJAXOutputDriverWebServerClass *_server;
+};
+
+#endif

README.md

@@ -53,19 +53,27 @@ The following additional features may be of interest (supported as of now):
 - Allows to insert your own custom CSS for styling (no styling in the lib).
 - Elements can be hidden, inputs can be disabled from the server (EmbAJAXBase::setVisible(), setEnabled()).
 
-## Example sketch (compilable on ESP8266)
+### Hardware support
+
+Currently there are output drivers for ESP8266 and ESP32. However, drivers are really easy to add. All that is needed is a very
+basic abstraction across some web server calls.
+
+ESP8266 support is solid. ESP32-support is currently plagued by a bug in the ESP32's networking code, that causes incoming connections
+to fail under some circumstances (https://github.com/espressif/arduino-esp32/issues/1921).
+
+
+## Example sketch
 
 Not really useful, but you know what to really do with a slider, and a display, right?
 Some further examples can be found in the examples folder.
 
 ```cpp
-#include <ESP8266WiFi.h>
-#include <ESP8266WebServer.h>
 #include <EmbAJAX.h>
 
-// Set up web server, and register it with EmbAJAX
-ESP8266WebServer server(80);
-EmbAJAXOutputDriverESP8266 driver(&server);
+// Set up web server, and register it with EmbAJAX. Note: EmbAJAXOutputDirverWebServerClass is a
+// converience #define to allow using the same example code across platforms
+EmbAJAXOutputDriverWebServerClass server(80);
+EmbAJAXOutputDriver driver(&server);
 
 // Define the main elements of interest as variables, so we can access them later in our sketch.
 EmbAJAXSlider slider("slider", 0, 500, 400);   // slider, from 0 to 500, initial value 400

examples/Blink/Blink.ino

@@ -1,24 +1,21 @@
 /* Basic usage example for EmbAJAX library:
  * Provide a web interface to set built-in LED on, off, or blinking.
  * 
- * This example is based on an ESP8266 with Arduino core (https://github.com/esp8266/Arduino).
- * 
  * Note that ESP boards seems to be no real standard on which pin the builtin LED is on, and
  * there is a very real chance that LED_BUILTIN is not defined, correctly, for your board.
  * If you see no blinking, try changing the LEDPIN define (with an externally connected LED
- * on a known pin being the safest option).
+ * on a known pin being the safest option). Similarly, on and off states are sometimes reversed.
  * 
  * This example code is in the public domain (CONTRARY TO THE LIBRARY ITSELF). */
 
-#include <ESP8266WiFi.h>
-#include <ESP8266WebServer.h>
 #include <EmbAJAX.h>
 
 #define LEDPIN LED_BUILTIN
 
-// Set up web server, and register it with EmbAJAX
-ESP8266WebServer server(80);
-EmbAJAXOutputDriverESP8266 driver(&server);
+// Set up web server, and register it with EmbAJAX. Note: EmbAJAXOutputDirverWebServerClass is a
+// converience #define to allow using the same example code across platforms
+EmbAJAXOutputDriverWebServerClass server(80);
+EmbAJAXOutputDriver driver(&server);
 
 // Define the main elements of interest as variables, so we can access to them later in our sketch.
 const char* modes[] = {"On", "Blink", "Off"};

examples/Inputs/Inputs.ino

@@ -3,18 +3,15 @@
 * of this writing. The right hand side has displays to show some sort of value for each (after a
 * round-trip to the server).
 * 
-* This example is based on an ESP8266 with Arduino core (https://github.com/esp8266/Arduino).
-* 
 * This example code is in the public domain (CONTRARY TO THE LIBRARY ITSELF). */
 
-#include <ESP8266WiFi.h>
-#include <ESP8266WebServer.h>
 #include <EmbAJAX.h>
 #include <EmbAJAXValidatingTextInput.h> // Fancier text input in a separate header file
 
-// Set up web server, and register it with EmbAJAX
-ESP8266WebServer server(80);
-EmbAJAXOutputDriverESP8266 driver(&server);
+// Set up web server, and register it with EmbAJAX. Note: EmbAJAXOutputDirverWebServerClass is a
+// converience #define to allow using the same example code across platforms
+EmbAJAXOutputDriverWebServerClass server(80);
+EmbAJAXOutputDriver driver(&server);
 
 #define BUFLEN 30
 

examples/TwoPages/TwoPages.ino

@@ -1,19 +1,16 @@
 /* Basic usage example for EmbAJAX library:
  * Demonstrate using two pages with shared controls
  * 
- * This example is based on an ESP8266 with Arduino core (https://github.com/esp8266/Arduino).
- * 
  * This example code is in the public domain (CONTRARY TO THE LIBRARY ITSELF). */
 
-#include <ESP8266WiFi.h>
-#include <ESP8266WebServer.h>
 #include <EmbAJAX.h>
 
 #define LEDPIN LED_BUILTIN
 
-// Set up web server, and register it with EmbAJAX
-ESP8266WebServer server(80);
-EmbAJAXOutputDriverESP8266 driver(&server);
+// Set up web server, and register it with EmbAJAX. Note: EmbAJAXOutputDirverWebServerClass is a
+// converience #define to allow using the same example code across platforms
+EmbAJAXOutputDriverWebServerClass server(80);
+EmbAJAXOutputDriver driver(&server);
 
 // Define the main elements of interest as variables, so we can access to them later in our sketch.
 EmbAJAXSlider shared_slider("shared_slider", 0, 1000, 100);

examples/Visibility/Visibility.ino

@@ -3,17 +3,14 @@
 * This example shows the semantics of calling setVisible() and setEnabled() on the various
 * elements.
 * 
-* This example is based on an ESP8266 with Arduino core (https://github.com/esp8266/Arduino).
-* 
 * This example code is in the public domain (CONTRARY TO THE LIBRARY ITSELF). */
 
-#include <ESP8266WiFi.h>
-#include <ESP8266WebServer.h>
 #include <EmbAJAX.h>
 
-// Set up web server, and register it with EmbAJAX
-ESP8266WebServer server(80);
-EmbAJAXOutputDriverESP8266 driver(&server);
+// Set up web server, and register it with EmbAJAX. Note: EmbAJAXOutputDirverWebServerClass is a
+// converience #define to allow using the same example code across platforms
+EmbAJAXOutputDriverWebServerClass server(80);
+EmbAJAXOutputDriver driver(&server);
 
 // The radio groups will be used to control the state
 const char* visibility_opts[] = {"Normal", "Hidden", "Disabled"};