Add HTTPClient, ported from the ESP8266 (#784)

Remove the need to have a separate WiFiClient that's destroyed after
the HTTPClient.  Let the object handle its own client, and pass through
any SSL requests.

Also supports the original ::begin methods which need a
WiFiClient(Secure) to be passed in and managed by the app.

Author: earlephilhower

docs/httpclient.rst

@@ -0,0 +1,40 @@
+HTTPClient Library
+==================
+
+A simple HTTP requestor that can handle both HTTP and HTTP requests is
+included as the ``HTTPClient`` library.
+
+Check the examples for use under HTTP and HTTPS configurations.  In general,
+for HTTP connections (unsecured and very uncommon on the internet today) simply
+passing in a URL and performiung a GET is sufficient to transfer data.
+
+.. code:: cpp
+
+    // Error checking is left as an exercise for the reader...
+    HTTPClient http;
+    if (http.begin("http://my.server/url")) {
+        if (http.GET() > 0) {
+            String data = http.getString();
+        }
+        http.end();
+    }
+
+For HTTPS connections, simply add the appropriate WiFiClientSecure calls
+as needed (i.e. ``setInsecure()``, ``setTrustAnchor``, etc.).  See the
+WiFiClientSecure documentation for more details.
+
+.. code:: cpp
+
+    // Error checking is left as an exercise for the reader...
+    HTTPClient https;
+    https.setInsecure(); // Use certs, but do not check their authenticity
+    if (https.begin("https://my.secure.server/url")) {
+        if (http.GET() > 0) {
+            String data = http.getString();
+        }
+        http.end();
+    }
+
+Unlike the ESP8266 and ESP32 ``HTTPClient`` implementations it is not necessary
+to create a ``WiFiClient`` or ``WiFiClientSecure`` to pass in to the ``HTTPClient``
+object.

docs/index.rst

@@ -50,6 +50,8 @@ For the latest version, always check https://github.com/earlephilhower/arduino-p
    WiFiClientSecure (TLS/SSL/HTTPS) <bearssl-client-secure-class>
    WiFiServerSecure (TLS/SSL/HTTPS) <bearssl-server-secure-class>
 
+   HTTP/HTTPS Client <httpclient>
+
    Over-the-Air (OTA) Updates <ota>
 
    Ported/Optimized Libraries <libraries>

keywords.txt

@@ -2,6 +2,8 @@
 # Syntax Coloring Map
 #######################################
 
+Arduino	KEYWORD3		RESERVED_WORD
+
 #######################################
 # Datatypes (KEYWORD1)
 #######################################

libraries/HTTPClient/examples/Authorization/Authorization.ino

@@ -0,0 +1,87 @@
+/**
+   Authorization.ino
+
+    Created on: 09.12.2015
+
+*/
+
+#include <Arduino.h>
+#include <WiFi.h>
+#include <HTTPClient.h>
+
+#ifndef STASSID
+#define STASSID "your-ssid"
+#define STAPSK "your-password"
+#endif
+
+const char *ssid = STASSID;
+const char *pass = STAPSK;
+
+WiFiMulti WiFiMulti;
+
+void setup() {
+
+  Serial.begin(115200);
+  // Serial.setDebugOutput(true);
+
+  Serial.println();
+  Serial.println();
+  Serial.println();
+
+  for (uint8_t t = 4; t > 0; t--) {
+    Serial.printf("[SETUP] WAIT %d...\n", t);
+    Serial.flush();
+    delay(1000);
+  }
+
+  WiFi.mode(WIFI_STA);
+  WiFiMulti.addAP(ssid, pass);
+}
+
+void loop() {
+  // wait for WiFi connection
+  if ((WiFiMulti.run() == WL_CONNECTED)) {
+
+    HTTPClient http;
+    http.setInsecure();
+
+    Serial.print("[HTTP] begin...\n");
+    // configure traged server and url
+
+
+    http.begin("https://guest:guest@jigsaw.w3.org/HTTP/Basic/");
+
+    /*
+      // or
+      http.begin(client, "http://jigsaw.w3.org/HTTP/Basic/");
+      http.setAuthorization("guest", "guest");
+
+      // or
+      http.begin(client, "http://jigsaw.w3.org/HTTP/Basic/");
+      http.setAuthorization("Z3Vlc3Q6Z3Vlc3Q=");
+    */
+
+
+    Serial.print("[HTTP] GET...\n");
+    // start connection and send HTTP header
+    int httpCode = http.GET();
+
+    // httpCode will be negative on error
+    if (httpCode > 0) {
+      // HTTP header has been send and Server response header has been handled
+      Serial.printf("[HTTP] GET... code: %d\n", httpCode);
+
+      // file found at server
+      if (httpCode == HTTP_CODE_OK) {
+        String payload = http.getString();
+        Serial.println(payload);
+      }
+    } else {
+      Serial.printf("[HTTP] GET... failed, error: %s\n", http.errorToString(httpCode).c_str());
+    }
+
+    http.end();
+  }
+
+  delay(10000);
+}

libraries/HTTPClient/examples/BasicHttpClient/BasicHttpClient.ino

@@ -0,0 +1,75 @@
+/**
+   BasicHTTPClient.ino
+
+   Created on: 24.05.2015
+
+*/
+
+#include <Arduino.h>
+#include <WiFi.h>
+#include <HTTPClient.h>
+
+#ifndef STASSID
+#define STASSID "your-ssid"
+#define STAPSK "your-password"
+#endif
+
+const char *ssid = STASSID;
+const char *pass = STAPSK;
+
+WiFiMulti WiFiMulti;
+
+void setup() {
+
+  Serial.begin(115200);
+  // Serial.setDebugOutput(true);
+
+  Serial.println();
+  Serial.println();
+  Serial.println();
+
+  for (uint8_t t = 4; t > 0; t--) {
+    Serial.printf("[SETUP] WAIT %d...\n", t);
+    Serial.flush();
+    delay(1000);
+  }
+
+  WiFiMulti.addAP(ssid, pass);
+}
+
+void loop() {
+  // wait for WiFi connection
+  if ((WiFiMulti.run() == WL_CONNECTED)) {
+
+    HTTPClient http;
+
+    Serial.print("[HTTP] begin...\n");
+    if (http.begin("http://httpbin.org")) {  // HTTP
+
+
+      Serial.print("[HTTP] GET...\n");
+      // start connection and send HTTP header
+      int httpCode = http.GET();
+
+      // httpCode will be negative on error
+      if (httpCode > 0) {
+        // HTTP header has been send and Server response header has been handled
+        Serial.printf("[HTTP] GET... code: %d\n", httpCode);
+
+        // file found at server
+        if (httpCode == HTTP_CODE_OK || httpCode == HTTP_CODE_MOVED_PERMANENTLY) {
+          String payload = http.getString();
+          Serial.println(payload);
+        }
+      } else {
+        Serial.printf("[HTTP] GET... failed, error: %s\n", http.errorToString(httpCode).c_str());
+      }
+
+      http.end();
+    } else {
+      Serial.printf("[HTTP} Unable to connect\n");
+    }
+  }
+
+  delay(10000);
+}

libraries/HTTPClient/examples/BasicHttpsClient-Hard/BasicHttpsClient-Hard.ino

@@ -0,0 +1,80 @@
+/**
+   BasicHTTPSClient-Hard.ino
+
+   Demonstrates the manual way of making a WiFiClient and passing it in to the HTTPClient
+
+   Created on: 20.08.2018
+
+*/
+
+#include <Arduino.h>
+#include <WiFi.h>
+#include <HTTPClient.h>
+
+#ifndef STASSID
+#define STASSID "your-ssid"
+#define STAPSK "your-password"
+#endif
+
+const char *ssid = STASSID;
+const char *pass = STAPSK;
+
+WiFiMulti WiFiMulti;
+
+void setup() {
+
+  Serial.begin(115200);
+
+  Serial.println();
+  Serial.println();
+  Serial.println();
+
+  for (uint8_t t = 4; t > 0; t--) {
+    Serial.printf("[SETUP] WAIT %d...\n", t);
+    Serial.flush();
+    delay(1000);
+  }
+
+  WiFi.mode(WIFI_STA);
+  WiFiMulti.addAP(ssid, pass);
+}
+
+void loop() {
+  // wait for WiFi connection
+  if ((WiFiMulti.run() == WL_CONNECTED)) {
+
+    WiFiClientSecure client;
+    client.setInsecure(); // Not safe against MITM attacks
+
+    HTTPClient https;
+
+    Serial.print("[HTTPS] begin...\n");
+    if (https.begin(client, "https://jigsaw.w3.org/HTTP/connection.html")) {  // HTTPS
+
+      Serial.print("[HTTPS] GET...\n");
+      // start connection and send HTTP header
+      int httpCode = https.GET();
+
+      // httpCode will be negative on error
+      if (httpCode > 0) {
+        // HTTP header has been send and Server response header has been handled
+        Serial.printf("[HTTPS] GET... code: %d\n", httpCode);
+
+        // file found at server
+        if (httpCode == HTTP_CODE_OK || httpCode == HTTP_CODE_MOVED_PERMANENTLY) {
+          String payload = https.getString();
+          Serial.println(payload);
+        }
+      } else {
+        Serial.printf("[HTTPS] GET... failed, error: %s\n", https.errorToString(httpCode).c_str());
+      }
+
+      https.end();
+    } else {
+      Serial.printf("[HTTPS] Unable to connect\n");
+    }
+  }
+
+  Serial.println("Wait 10s before next round...");
+  delay(10000);
+}