ESP32-http client笔记

基于ESP-IDF4.1

#include <string.h>
#include <stdlib.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_log.h"
#include "esp_system.h"
#include "nvs_flash.h"
#include "esp_event.h"
#include "esp_netif.h"
#include "protocol_examples_common.h"
#include "esp_tls.h"

#include "esp_http_client.h"

#define MAX_HTTP_RECV_BUFFER 512
static const char *TAG = "HTTP_CLIENT";

//Http事件处理程序
esp_err_t _http_event_handler(esp_http_client_event_t *evt)
{
    switch(evt->event_id) {
        case HTTP_EVENT_ERROR:
            ESP_LOGD(TAG, "HTTP_EVENT_ERROR");
            break;
        case HTTP_EVENT_ON_CONNECTED:
            ESP_LOGD(TAG, "HTTP_EVENT_ON_CONNECTED");
            break;
        case HTTP_EVENT_HEADER_SENT:
            ESP_LOGD(TAG, "HTTP_EVENT_HEADER_SENT");
            break;
        case HTTP_EVENT_ON_HEADER:
            ESP_LOGD(TAG, "HTTP_EVENT_ON_HEADER, key=%s, value=%s", evt->header_key, evt->header_value);
            break;
        case HTTP_EVENT_ON_DATA:
            ESP_LOGD(TAG, "HTTP_EVENT_ON_DATA, len=%d", evt->data_len);
            if (!esp_http_client_is_chunked_response(evt->client)) {
                // Write out data
                // printf("%.*s", evt->data_len, (char*)evt->data);
            }

            break;
        case HTTP_EVENT_ON_FINISH:
            ESP_LOGD(TAG, "HTTP_EVENT_ON_FINISH");
            break;
        case HTTP_EVENT_DISCONNECTED:
            ESP_LOGI(TAG, "HTTP_EVENT_DISCONNECTED");
            int mbedtls_err = 0;
            esp_err_t err = esp_tls_get_and_clear_last_error(evt->data, &mbedtls_err, NULL);
            if (err != 0) {
                ESP_LOGI(TAG, "Last esp error code: 0x%x", err);
                ESP_LOGI(TAG, "Last mbedtls failure: 0x%x", mbedtls_err);
            }
            break;
    }
    return ESP_OK;
}

static void http_rest_with_url(void)
{
    esp_http_client_config_t config = {
        .url = "http://httpbin.org/get",
        .event_handler = _http_event_handler,
    };
    esp_http_client_handle_t client = esp_http_client_init(&config);

    // GET
    esp_err_t err = esp_http_client_perform(client);
    if (err == ESP_OK) {
        ESP_LOGI(TAG, "HTTP GET Status = %d, content_length = %d",
                esp_http_client_get_status_code(client),
                esp_http_client_get_content_length(client));
    } else {
        ESP_LOGE(TAG, "HTTP GET request failed: %s", esp_err_to_name(err));
    }

    // POST
    const char *post_data = "field1=value1&field2=value2";
    esp_http_client_set_url(client, "http://httpbin.org/post");
    esp_http_client_set_method(client, HTTP_METHOD_POST);
    esp_http_client_set_post_field(client, post_data, strlen(post_data));
    err = esp_http_client_perform(client);
    if (err == ESP_OK) {
        ESP_LOGI(TAG, "HTTP POST Status = %d, content_length = %d",
                esp_http_client_get_status_code(client),
                esp_http_client_get_content_length(client));
    } else {
        ESP_LOGE(TAG, "HTTP POST request failed: %s", esp_err_to_name(err));
    }

    //PUT
    esp_http_client_set_url(client, "http://httpbin.org/put");
    esp_http_client_set_method(client, HTTP_METHOD_PUT);
    err = esp_http_client_perform(client);
    if (err == ESP_OK) {
        ESP_LOGI(TAG, "HTTP PUT Status = %d, content_length = %d",
                esp_http_client_get_status_code(client),
                esp_http_client_get_content_length(client));
    } else {
        ESP_LOGE(TAG, "HTTP PUT request failed: %s", esp_err_to_name(err));
    }

    //PATCH
    esp_http_client_set_url(client, "http://httpbin.org/patch");
    esp_http_client_set_method(client, HTTP_METHOD_PATCH);
    esp_http_client_set_post_field(client, NULL, 0);
    err = esp_http_client_perform(client);
    if (err == ESP_OK) {
        ESP_LOGI(TAG, "HTTP PATCH Status = %d, content_length = %d",
                esp_http_client_get_status_code(client),
                esp_http_client_get_content_length(client));
    } else {
        ESP_LOGE(TAG, "HTTP PATCH request failed: %s", esp_err_to_name(err));
    }

    //DELETE
    esp_http_client_set_url(client, "http://httpbin.org/delete");
    esp_http_client_set_method(client, HTTP_METHOD_DELETE);
    err = esp_http_client_perform(client);
    if (err == ESP_OK) {
        ESP_LOGI(TAG, "HTTP DELETE Status = %d, content_length = %d",
                esp_http_client_get_status_code(client),
                esp_http_client_get_content_length(client));
    } else {
        ESP_LOGE(TAG, "HTTP DELETE request failed: %s", esp_err_to_name(err));
    }

    //HEAD
    esp_http_client_set_url(client, "http://httpbin.org/get");
    esp_http_client_set_method(client, HTTP_METHOD_HEAD);
    err = esp_http_client_perform(client);
    if (err == ESP_OK) {
        ESP_LOGI(TAG, "HTTP HEAD Status = %d, content_length = %d",
                esp_http_client_get_status_code(client),
                esp_http_client_get_content_length(client));
    } else {
        ESP_LOGE(TAG, "HTTP HEAD request failed: %s", esp_err_to_name(err));
    }

    esp_http_client_cleanup(client);
}


static void http_perform_as_stream_reader(void)
{
    char *buffer = malloc(MAX_HTTP_RECV_BUFFER + 1);
    if (buffer == NULL) {
        ESP_LOGE(TAG, "Cannot malloc http receive buffer");
        return;
    }
    esp_http_client_config_t config = {
        .url = "http://httpbin.org/get",
        .event_handler = _http_event_handler,
    };
    esp_http_client_handle_t client = esp_http_client_init(&config);
    esp_err_t err;
    if ((err = esp_http_client_open(client, 0)) != ESP_OK) {
        ESP_LOGE(TAG, "Failed to open HTTP connection: %s", esp_err_to_name(err));
        free(buffer);
        return;
    }
    int content_length =  esp_http_client_fetch_headers(client);
    int total_read_len = 0, read_len;
    if (total_read_len < content_length && content_length <= MAX_HTTP_RECV_BUFFER) {
        read_len = esp_http_client_read(client, buffer, content_length);
        if (read_len <= 0) {
            ESP_LOGE(TAG, "Error read data");
        }
        buffer[read_len] = 0;
        ESP_LOGD(TAG, "read_len = %d", read_len);
    }
    ESP_LOGI(TAG, "HTTP Stream reader Status = %d, content_length = %d",
                    esp_http_client_get_status_code(client),
                    esp_http_client_get_content_length(client));
    esp_http_client_close(client);
    esp_http_client_cleanup(client);
    free(buffer);
}

//任务
static void http_test_task(void *pvParameters)
{
    http_rest_with_url();
    http_perform_as_stream_reader();

    ESP_LOGI(TAG, "Finish http example");
    vTaskDelete(NULL);
}

void app_main(void)
{
    esp_err_t ret = nvs_flash_init();
    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
      ESP_ERROR_CHECK(nvs_flash_erase());
      ret = nvs_flash_init();
    }
    ESP_ERROR_CHECK(ret);
    ESP_ERROR_CHECK(esp_netif_init());
    ESP_ERROR_CHECK(esp_event_loop_create_default());

    //连接网络
    ESP_ERROR_CHECK(example_connect());
    ESP_LOGI(TAG, "Connected to AP, begin http example");

    xTaskCreate(&http_test_task, "http_test_task", 8192, NULL, 5, NULL);
}

原文：https://gitee.com/EspressifSystems/esp-idf