Reworked all examples

This commit is contained in:
Benoit Blanchon
2017-12-11 15:19:28 +01:00
parent 57d98e48f7
commit 461e30148c
8 changed files with 308 additions and 152 deletions

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@ -2,9 +2,10 @@
// Copyright Benoit Blanchon 2014-2017
// MIT License
//
// Example of an HTTP client parsing a JSON response.
// This example shows how to parse a JSON document in an HTTP response.
// It uses the Ethernet library, but can be easily adapter for Wifi.
//
// This program perform an HTTP GET of arduinojson.org/example.json
// It performs a GET resquest on arduinojson.org/example.json
// Here is the expected response:
// {
// "sensor": "gps",
@ -14,73 +15,98 @@
// 2.302038
// ]
// }
// See http://arduinojson.org/assistant/ to compute the size of the buffer.
//
// Disclaimer: the code emphasize the communication between client and server,
// it doesn't claim to be a reference of good coding practices.
#include <ArduinoJson.h>
#include <Ethernet.h>
#include <SPI.h>
void setup() {
// Initialize Serial port
Serial.begin(9600);
while (!Serial);
while (!Serial) continue;
echo("Initialize Ethernet library");
// Initialize Ethernet library
byte mac[] = {0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED};
Ethernet.begin(mac) || die("Failed to configure Ethernet");
if (!Ethernet.begin(mac)) {
Serial.println(F("Failed to configure Ethernet"));
return;
}
delay(1000);
echo("Connect to HTTP server");
Serial.println(F("Connecting..."));
// Connect to HTTP server
EthernetClient client;
client.setTimeout(10000);
client.connect("arduinojson.org", 80) || die("Connection failed");
if (!client.connect("arduinojson.org", 80)) {
Serial.println(F("Connection failed"));
return;
}
echo("Send HTTP request");
client.println("GET /example.json HTTP/1.0");
client.println("Host: arduinojson.org");
client.println("Connection: close");
client.println() || die("Failed to send request");
Serial.println(F("Connected!"));
echo("Check HTTP status");
// Send HTTP request
client.println(F("GET /example.json HTTP/1.0"));
client.println(F("Host: arduinojson.org"));
client.println(F("Connection: close"));
if (client.println() == 0) {
Serial.println(F("Failed to send request"));
return;
}
// Check HTTP status
char status[32] = {0};
client.readBytesUntil('\r', status, sizeof(status));
if (strcmp(status, "HTTP/1.1 200 OK") != 0) {
echo(status);
die("Unexpected HTTP response");
Serial.print(F("Unexpected response: "));
Serial.println(status);
return;
}
echo("Skip HTTP headers");
// Skip HTTP headers
char endOfHeaders[] = "\r\n\r\n";
client.find(endOfHeaders) || die("Invalid response");
if (!client.find(endOfHeaders)) {
Serial.println(F("Invalid response"));
return;
}
echo("Allocate JsonBuffer");
const size_t BUFFER_SIZE = JSON_OBJECT_SIZE(3) + JSON_ARRAY_SIZE(2) + 60;
DynamicJsonBuffer jsonBuffer(BUFFER_SIZE);
// Allocate JsonBuffer
// (see https://arduinojson.org/assistant/ to compute the capacity)
const size_t capacity = JSON_OBJECT_SIZE(3) + JSON_ARRAY_SIZE(2) + 60;
DynamicJsonBuffer jsonBuffer(capacity);
echo("Parse JSON object");
// Parse JSON object
JsonObject& root = jsonBuffer.parseObject(client);
if (!root.success()) die("Parsing failed!");
if (!root.success()) {
Serial.println(F("Parsing failed!"));
return;
}
echo("Extract values");
echo(root["sensor"].as<char*>());
echo(root["time"].as<char*>());
echo(root["data"][0].as<char*>());
echo(root["data"][1].as<char*>());
// Extract values
Serial.println(F("Response:"));
Serial.println(root["sensor"].as<char*>());
Serial.println(root["time"].as<char*>());
Serial.println(root["data"][0].as<char*>());
Serial.println(root["data"][1].as<char*>());
echo("Disconnect");
// Disconnect
client.stop();
}
void loop() {}
void echo(const char* message) {
Serial.println(message);
void loop() {
// not used in this example
}
bool die(const char* message) {
Serial.println(message);
while (true); // loop forever
return false;
}
// See also
// --------
//
// The website arduinojson.org contains the documentation for all the functions
// used above. It also includes an FAQ that will help you solve any
// serialization problem.
// Please check it out at: https://arduinojson.org/
//
// The book "Mastering ArduinoJson" contains a tutorial on deserialization
// showing how to parse the response from Yahoo Weather. In the last chapter,
// it shows how to parse the huge documents from OpenWeatherMap
// and Weather Underground.
// Please check it out at: https://leanpub.com/arduinojson/