Rename project.

.gitignore

@@ -1,3 +1,4 @@
 config.h
 *.bin
 *.elf
+configs/

config.h.example

@@ -1,3 +1,7 @@
+// Do not edit these two lines
+#ifndef __CONFIG_H__
+#define __CONFIG_H__
+
 #define WIFI_SSID "myNetwork"
 #define WIFI_PASSWORD "myPassword"
 #define WEBHOOK_URL "example.com/aoeuhtns"
@@ -8,12 +12,58 @@
 //
 // We would expect the webhook to return something like:
 //
-// [1 0 1]
+// [1, 0, 1]
 //
 // to activate the momentary switch, (pin 5) deactivate the first
 // latched switch, (pin 8) and activate the second latched switch. (pin 10)
-const int PIN_MAP[][2] = {
+const int NUM_PINS = 3;
+const int PIN_MAP[NUM_PINS][2] = {
                                   {5, 1},
                                   {8, 1},
                                   {10, 1}
 };
+
+// The signing/root certificate for your webhook site.
+// For internal installations this might be a self-signing cert.
+// For public installations, acquire the root cert for the CA and
+// place it here. You can get this for your target domain with:
+//
+// sudo openssl s_client -connect sss.annabunch.es:443 -showcerts
+//
+// Be sure that you copy the cert that is described as a "Root CA" or
+// "Root Trust" certificate.
+//
+// The provided example is for letsencrypt.org
+static const char ca_cert[] PROGMEM = R"EOF(
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
+)EOF";
+
+
+// Do not edit this line
+#endif

gpio-webhook-arduino.ino

@@ -19,31 +19,6 @@ const int OLD_HIGH = 255;
 // Gets read from by set_pins().
 int pin_states[NUM_PINS] = {0};
 
-void init_serial() {
-  Serial.begin(9600);
-}
-
-void init_pins() {
-  for (int i = 0; i < NUM_PINS; i++) {
-    digitalWrite(PIN_MAP[i][0], LOW);
-  }
-}
-
-void setup() {
-  init_pins();
-  init_serial();
-  init_wifi();
-}
-
-void loop() {
-  poll_server();
-  set_pins();
-  int elapsed = handle_momentary();
-
-  Serial.flush();
-  delay(REQUEST_RATE - elapsed);
-}
-
 // if any momentary pins went high this loop, we
 // wait the agreed upon delay and then turn them off.
 // if any momentary data input went low, we "reset"
@@ -81,20 +56,10 @@ int handle_momentary() {
 // poll_server makes the actual HTTP request and handles
 // the result. It returns false if an error occurred.
 bool poll_server() {
-  client.begin(transport, WEBHOOK_URL);
+  String data = FetchURL(WEBHOOK_URL);
-  int status = client.GET();
+  if (data == "") return false;
-  if (status < 0) {
+  parse_webhook_response(data);
-    Serial.print("Client error communicating with server: ");
+  return true;
-    Serial.println(status);
-    return false;
-  }
-  if (status <= 400) {
-    Serial.print("Received HTTP status code ");
-    Serial.println(status);
-    return false;
-  }
-
-  parse_webhook_response(client.getString());
 }
 
 void parse_webhook_response(String raw_data) {
@@ -122,8 +87,18 @@ void parse_webhook_response(String raw_data) {
   }
 }
 
+// Set the pins to the right state, and set them all to high during
+// initialization.
+void initPins() {
+  for (int i = 0; i < NUM_PINS; i++) {
+    pinMode(PIN_MAP[i][0], OUTPUT);
+    digitalWrite(PIN_MAP[i][0], HIGH);
+  }
+
+}
+
 // Uses the current pin_states to actually write to the pins
-void set_pins() {
+void writePins() {
   for (int i = 0; i < NUM_PINS; i++) {
     if (tripped(i)) {
       continue;
@@ -139,3 +114,18 @@ void set_pins() {
 bool tripped(int i) {
   return PIN_MAP[i][1] == 0 && pin_states[i] == OLD_HIGH;
 }
+
+void setup() {
+  Serial.begin(9600);
+  initPins();
+  InitWifi();
+}
+
+void loop() {
+  poll_server();
+  writePins();
+  int elapsed = handle_momentary();
+
+  Serial.flush();
+  delay(REQUEST_RATE - elapsed);
+}

readme.md

@@ -1,13 +1,14 @@
 # Control I/O pins with a webhook
 
 This is an Arduino IDE sketch for a "smart" controller that can activate pins
-based on the state of some webpage. The motivating use cases are:
+based on the state of some webpage. (designed to be driven by [gpio webhook server](https://git.annabunch.es/annabunches/gpio-webhook-server))
+The motivating use cases are:
 
 * Controlling a PC power switch remotely, using a transistor wired to the power switch pins
 * Lighting specific LEDs to create a remotely controlled 'traffic light'.
 
 This sketch currently targets only the ESP8266, and will probably not work with other
-microcontrollers. Support for other boards may come if I run out of ESP8266's.
+microcontrollers. Support for other boards may come if I run out of ESP8266s.
 
 ## Configuration
 

wifi.h

@@ -1,17 +1,39 @@
+#include "config.h"
 #include <ESP8266WiFi.h>
 #include <ESP8266HTTPClient.h>
-//#include <WifiClientSecureBearSSL.h>
+#include <WiFiClientSecureBearSSL.h>
-#include <bearssl.h>
-#include <FS.h>
 
 HTTPClient client;
-BearSSL::WifiClientSecure *transport;
+BearSSL::WiFiClientSecure *secure_transport;
+BearSSL::Session *tls_session;
 BearSSL::X509List cert_list;
 
-void init_wifi() {
+void syncTime() {
-  transport = new WifiClientSecure();
+  // sync time
+  Serial.print("Syncing time");
+  configTime(8 * 3600, 0, "pool.ntp.org", "time.nist.gov");
+  time_t now = time(nullptr);
+  while (now < 8 * 3600 * 2) {
+    delay(500);
+    Serial.print(".");
+    now = time(nullptr);
+  }
+  Serial.println("");
+}
 
-  Serial.println("Attempting to (re)connect to wifi");
+void initTLS() {
+  secure_transport = new BearSSL::WiFiClientSecure();
+
+  syncTime();
+  cert_list.append(ca_cert);
+  secure_transport->setTrustAnchors(&cert_list);
+
+  tls_session = new BearSSL::Session();
+  secure_transport->setSession(tls_session);
+}
+
+void InitWifi() {
+  Serial.println("Attempting to connect to wifi");
   WiFi.disconnect();
   WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
   int elapsed = 0;
@@ -25,36 +47,23 @@ void init_wifi() {
 
   Serial.println("Wifi connected");
   
-  sync_time();
+  initTLS();
-  load_ca_cert();
 }
 
-void load_ca_cert() {
+String FetchURL(const char *path) {
-  // read cert from file
+  client.begin(*secure_transport, WEBHOOK_URL);
-  if (!SPIFFS.begin()) {
+
-    Serial.println("Failed to mount file system.");
+  int status = client.GET();
-    return
+  if (status < 0) {
+    Serial.print("Client error communicating with server: ");
+    Serial.println(status);
+    return "";
+  }
+  if (status >= 400) {
+    Serial.print("Received HTTP status code ");
+    Serial.println(status);
+    return "";
   }
 
-  File cert = SPIFFS.open("/ca_cert.pem", "r");
+  return client.getString();
-  if (!cert) {
-    Serial.println("Couldn't open cert file.");
-    return;
-  }
-
-  cert_list.append(strdup(cert.readString().c_str()));
-  netClient->setTrustAnchors(&certList);
-}
-
-void sync_time() {
-  // sync time
-  Serial.print("Syncing time");
-  configTime(8 * 3600, 0, "pool.ntp.org", "time.nist.gov");
-  time_t now = time(nullptr);
-  while (now < 8 * 3600 * 2) {
-    delay(500);
-    Serial.print(".");
-    now = time(nullptr);
-  }
-  Serial.println("");
 }