mirror of
https://github.com/eledio-devices/thirdparty-ArduinoJson.git
synced 2025-10-31 00:32:37 +01:00
Rewrote example JsonHttpClient.ino (fixes #600)
This commit is contained in:
Benoit Blanchon
10
CHANGELOG.md
10
CHANGELOG.md
@@ -1,6 +1,10 @@
|
||||
ArduinoJson: change log
|
||||
=======================
|
||||
|
||||
HEAD
|
||||
----
|
||||
* Rewrote example `JsonHttpClient.ino` (issue #600)
|
||||
|
||||
v5.11.2
|
||||
-------
|
||||
|
||||
@@ -45,20 +49,20 @@ v5.10.0
|
||||
### BREAKING CHANGES :warning:
|
||||
|
||||
| Old syntax | New syntax |
|
||||
|---------------------------------|---------------------|
|
||||
|:--------------------------------|:--------------------|
|
||||
| `double_with_n_digits(3.14, 2)` | `3.14` |
|
||||
| `float_with_n_digits(3.14, 2)` | `3.14f` |
|
||||
| `obj.set("key", 3.14, 2)` | `obj["key"] = 3.14` |
|
||||
| `arr.add(3.14, 2)` | `arr.add(3.14)` |
|
||||
|
||||
| Input | Old output | New output |
|
||||
|-----------|------------|------------|
|
||||
|:----------|:-----------|:-----------|
|
||||
| `3.14159` | `3.14` | `3.14159` |
|
||||
| `42.0` | `42.00` | `42` |
|
||||
| `0.0` | `0.00` | `0` |
|
||||
|
||||
| Expression | Old result | New result |
|
||||
|--------------------------------|------------|------------|
|
||||
|:-------------------------------|:-----------|:-----------|
|
||||
| `JsonVariant(42).is<int>()` | `true` | `true` |
|
||||
| `JsonVariant(42).is<float>()` | `false` | `true` |
|
||||
| `JsonVariant(42).is<double>()` | `false` | `true` |
|
||||
|
||||
@@ -1,181 +1,86 @@
|
||||
// Sample Arduino Json Web Client
|
||||
// Downloads and parse http://jsonplaceholder.typicode.com/users/1
|
||||
//
|
||||
// ArduinoJson - arduinojson.org
|
||||
// Copyright Benoit Blanchon 2014-2017
|
||||
// MIT License
|
||||
//
|
||||
// Example of an HTTP client parsing a JSON response.
|
||||
//
|
||||
// This program perform an HTTP GET of arduinojson.org/example.json
|
||||
// Here is the expected response:
|
||||
// {
|
||||
// "sensor": "gps",
|
||||
// "time": 1351824120,
|
||||
// "data": [
|
||||
// 48.756080,
|
||||
// 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>
|
||||
|
||||
EthernetClient client;
|
||||
|
||||
const char* server = "jsonplaceholder.typicode.com"; // server's address
|
||||
const char* resource = "/users/1"; // http resource
|
||||
const unsigned long BAUD_RATE = 9600; // serial connection speed
|
||||
const unsigned long HTTP_TIMEOUT = 10000; // max respone time from server
|
||||
const size_t MAX_CONTENT_SIZE = 512; // max size of the HTTP response
|
||||
|
||||
// The type of data that we want to extract from the page
|
||||
struct UserData {
|
||||
char name[32];
|
||||
char company[32];
|
||||
};
|
||||
|
||||
// ARDUINO entry point #1: runs once when you press reset or power the board
|
||||
void setup() {
|
||||
initSerial();
|
||||
initEthernet();
|
||||
}
|
||||
Serial.begin(9600);
|
||||
while (!Serial);
|
||||
|
||||
// ARDUINO entry point #2: runs over and over again forever
|
||||
void loop() {
|
||||
if (connect(server)) {
|
||||
if (sendRequest(server, resource) && skipResponseHeaders()) {
|
||||
UserData userData;
|
||||
if (readReponseContent(&userData)) {
|
||||
printUserData(&userData);
|
||||
}
|
||||
}
|
||||
}
|
||||
disconnect();
|
||||
wait();
|
||||
}
|
||||
|
||||
// Initialize Serial port
|
||||
void initSerial() {
|
||||
Serial.begin(BAUD_RATE);
|
||||
while (!Serial) {
|
||||
; // wait for serial port to initialize
|
||||
}
|
||||
Serial.println("Serial ready");
|
||||
}
|
||||
|
||||
// Initialize Ethernet library
|
||||
void initEthernet() {
|
||||
echo("Initialize Ethernet library");
|
||||
byte mac[] = {0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED};
|
||||
if (!Ethernet.begin(mac)) {
|
||||
Serial.println("Failed to configure Ethernet");
|
||||
return;
|
||||
}
|
||||
Serial.println("Ethernet ready");
|
||||
Ethernet.begin(mac) || die("Failed to configure Ethernet");
|
||||
delay(1000);
|
||||
}
|
||||
|
||||
// Open connection to the HTTP server
|
||||
bool connect(const char* hostName) {
|
||||
Serial.print("Connect to ");
|
||||
Serial.println(hostName);
|
||||
echo("Connect to HTTP server");
|
||||
EthernetClient client;
|
||||
client.setTimeout(10000);
|
||||
client.connect("arduinojson.org", 80) || die("Connection failed");
|
||||
|
||||
bool ok = client.connect(hostName, 80);
|
||||
|
||||
Serial.println(ok ? "Connected" : "Connection Failed!");
|
||||
return ok;
|
||||
}
|
||||
|
||||
// Send the HTTP GET request to the server
|
||||
bool sendRequest(const char* host, const char* resource) {
|
||||
Serial.print("GET ");
|
||||
Serial.println(resource);
|
||||
|
||||
client.print("GET ");
|
||||
client.print(resource);
|
||||
client.println(" HTTP/1.0");
|
||||
client.print("Host: ");
|
||||
client.println(host);
|
||||
echo("Send HTTP request");
|
||||
client.println("GET /example.json HTTP/1.0");
|
||||
client.println("Host: arduinojson.org");
|
||||
client.println("Connection: close");
|
||||
client.println();
|
||||
client.println() || die("Failed to send request");
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
// Skip HTTP headers so that we are at the beginning of the response's body
|
||||
bool skipResponseHeaders() {
|
||||
// HTTP headers end with an empty line
|
||||
char endOfHeaders[] = "\r\n\r\n";
|
||||
|
||||
client.setTimeout(HTTP_TIMEOUT);
|
||||
bool ok = client.find(endOfHeaders);
|
||||
|
||||
if (!ok) {
|
||||
Serial.println("No response or invalid response!");
|
||||
echo("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");
|
||||
}
|
||||
|
||||
return ok;
|
||||
}
|
||||
echo("Skip HTTP headers");
|
||||
char endOfHeaders[] = "\r\n\r\n";
|
||||
client.find(endOfHeaders) || die("Invalid response");
|
||||
|
||||
// Parse the JSON from the input string and extract the interesting values
|
||||
// Here is the JSON we need to parse
|
||||
// {
|
||||
// "id": 1,
|
||||
// "name": "Leanne Graham",
|
||||
// "username": "Bret",
|
||||
// "email": "Sincere@april.biz",
|
||||
// "address": {
|
||||
// "street": "Kulas Light",
|
||||
// "suite": "Apt. 556",
|
||||
// "city": "Gwenborough",
|
||||
// "zipcode": "92998-3874",
|
||||
// "geo": {
|
||||
// "lat": "-37.3159",
|
||||
// "lng": "81.1496"
|
||||
// }
|
||||
// },
|
||||
// "phone": "1-770-736-8031 x56442",
|
||||
// "website": "hildegard.org",
|
||||
// "company": {
|
||||
// "name": "Romaguera-Crona",
|
||||
// "catchPhrase": "Multi-layered client-server neural-net",
|
||||
// "bs": "harness real-time e-markets"
|
||||
// }
|
||||
// }
|
||||
bool readReponseContent(struct UserData* userData) {
|
||||
// Compute optimal size of the JSON buffer according to what we need to parse.
|
||||
// See http://arduinojson.org/assistant/
|
||||
const size_t BUFFER_SIZE =
|
||||
JSON_OBJECT_SIZE(8) // the root object has 8 elements
|
||||
+ JSON_OBJECT_SIZE(5) // the "address" object has 5 elements
|
||||
+ JSON_OBJECT_SIZE(2) // the "geo" object has 2 elements
|
||||
+ JSON_OBJECT_SIZE(3) // the "company" object has 3 elements
|
||||
+ MAX_CONTENT_SIZE; // additional space for strings
|
||||
|
||||
// Allocate a temporary memory pool
|
||||
echo("Allocate JsonBuffer");
|
||||
const size_t BUFFER_SIZE = JSON_OBJECT_SIZE(3) + JSON_ARRAY_SIZE(2) + 60;
|
||||
DynamicJsonBuffer jsonBuffer(BUFFER_SIZE);
|
||||
|
||||
echo("Parse JSON object");
|
||||
JsonObject& root = jsonBuffer.parseObject(client);
|
||||
if (!root.success()) die("Parsing failed!");
|
||||
|
||||
if (!root.success()) {
|
||||
Serial.println("JSON parsing failed!");
|
||||
return false;
|
||||
}
|
||||
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*>());
|
||||
|
||||
// Here were copy the strings we're interested in
|
||||
strcpy(userData->name, root["name"]);
|
||||
strcpy(userData->company, root["company"]["name"]);
|
||||
// It's not mandatory to make a copy, you could just use the pointers
|
||||
// Since, they are pointing inside the "content" buffer, so you need to make
|
||||
// sure it's still in memory when you read the string
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
// Print the data extracted from the JSON
|
||||
void printUserData(const struct UserData* userData) {
|
||||
Serial.print("Name = ");
|
||||
Serial.println(userData->name);
|
||||
Serial.print("Company = ");
|
||||
Serial.println(userData->company);
|
||||
}
|
||||
|
||||
// Close the connection with the HTTP server
|
||||
void disconnect() {
|
||||
Serial.println("Disconnect");
|
||||
echo("Disconnect");
|
||||
client.stop();
|
||||
}
|
||||
|
||||
// Pause for a 1 minute
|
||||
void wait() {
|
||||
Serial.println("Wait 60 seconds");
|
||||
delay(60000);
|
||||
void loop() {}
|
||||
|
||||
void echo(const char* message) {
|
||||
Serial.println(message);
|
||||
}
|
||||
|
||||
bool die(const char* message) {
|
||||
Serial.println(message);
|
||||
while (true); // loop forever
|
||||
return false;
|
||||
}
|
||||
Reference in New Issue
Block a user