Add websocket example that supports permessage-deflate extension

examples/websocket_mbedtls/websocket_mbedtls.c

@@ -0,0 +1,108 @@
+/* websocket_mbedtls - Websocket example using mbed TLS.
+ *
+ * It creates a websocket with a server running on Heroku. It uses TLS v1.2.
+ * I already implemented support to the permessage-deflate extension that
+ * reduces the footprint of the websocket frames using the inflate deflate
+ * algorithm.
+
+ * The remaining memory when using the websocket on top of mbed TLS 1.2 is ~14Kb
+ *
+ * There is room for memory optimization. Feel free to improve the code.
+ *
+ * After get the esp8266 connected, go to ruby-websockets-chat.herokuapp.com
+ * and type some commands like break (to reconnect), turn led on and turn led off.
+ * 
+ * If you wanna check the source code from the server:
+ * https://github.com/heroku-examples/ruby-websockets-chat-demo
+ * 
+ * If you wanna work with the permessage-deflate extension, connect to the
+ * host serene-escarpment-15149.herokuapp.com and the path /echo . It is a websocket
+ * server echoing back your messages and supporting the permessage-deflate extension:
+ * https://github.com/luisbebop/websocket-echo-deflate
+ */
+
+#include "espressif/esp_common.h"
+#include "esp/uart.h"
+#include <string.h>
+#include "FreeRTOS.h"
+#include "task.h"
+#include "ssid_config.h"
+#include "conn.h"
+#include "ws.h"
+#include "util.h"
+
+const int gpio = 2;
+
+void websocket_task(void *pvParameters)
+{
+	//char * host = "serene-escarpment-15149.herokuapp.com";
+	//char * path = "/echo";
+	
+	char *host = "ruby-websockets-chat.herokuapp.com";
+	char *path = "/";
+	
+	int socket = 0, ret = 0;
+	int port = 443;
+	Bool compression = false, timeout = false;
+	char text[2048];
+	
+	gpio_enable(gpio, GPIO_OUTPUT);
+	gpio_write(gpio, 1);
+			
+    while(1) {
+		vTaskDelay(5000 / portTICK_RATE_MS);
+		printf("top of loop, free heap = %u\n", xPortGetFreeHeapSize());
+		
+		socket = ConnConnect(host, port);
+		printf("\nConnConnect socket %d\n", socket);
+		
+		ret = wsConnect(socket, host, path, &compression);
+		printf("wsConnect ret %d compression %d\n", ret, compression);
+	    if ( ret < 0)
+	    {
+	        printf("websocket handshake error ret=%d\n", ret);
+	    }
+			
+		strcpy(text, "{\"handle\":\"websocket-c-client\", \"text\": \"hello from low level ~*~ esp8266\"}");
+		wsSendText(socket, text, compression);
+		
+		while(1) {
+			printf("top of loop, free heap = %u\n", xPortGetFreeHeapSize());
+
+			memset(text, 0, sizeof(text));
+			wsReceiveText(socket, text, 2048, compression, &timeout, 15);
+
+			if (timeout) {
+				printf("wsReceiveText timeout\n");
+			} else {
+				printf("no timeout ...\n");
+				printf("%s\n", text);
+				
+				if(strstr(text, "break") != 0) break;
+				if(strstr(text, "turn led on") != 0) gpio_write(gpio, 0);
+				if(strstr(text, "turn led off") != 0) gpio_write(gpio, 1);
+			}
+		}
+		
+		printf("Before ConnClose top of loop, free heap = %u\n", xPortGetFreeHeapSize());
+		ConnClose(socket);
+		printf("After ConnClose top of loop, free heap = %u\n", xPortGetFreeHeapSize());
+    }
+}
+
+void user_init(void)
+{
+    uart_set_baud(0, 115200);
+    printf("SDK version:%s\n", sdk_system_get_sdk_version());
+
+    struct sdk_station_config config = {
+        .ssid = WIFI_SSID,
+        .password = WIFI_PASS,
+    };
+
+    /* required to call wifi_set_opmode before station_set_config */
+    sdk_wifi_set_opmode(STATION_MODE);
+    sdk_wifi_station_set_config(&config);
+
+    xTaskCreate(&websocket_task, (signed char *)"websocket_task", 2048, NULL, 2, NULL);
+}