Etlas project.

1 files changed, 183 insertions, 0 deletions

diff --git a/esp32/main/stock.c b/esp32/main/stock.c
new file mode 100644
index 0000000..832caaf
--- /dev/null
+++ b/esp32/main/stock.c
@@ -0,0 +1,183 @@
+#include <freertos/FreeRTOS.h>
+
+#include <assert.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <esp_log.h>
+#include <esp_tls.h>
+#include <esp_http_client.h>
+#include <sys/param.h>
+
+#include "stock.h"
+
+#define PRICE_LEN 15
+
+static char* TAG = "stock";
+static esp_http_client_handle_t http_client;
+
+static esp_err_t http_evt_handler(esp_http_client_event_t *evt)
+{
+	static int read_len;
+
+	switch(evt->event_id) {
+		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:
+			int copy_len = 0;
+			int cont_len = esp_http_client_get_content_length(evt->client);
+			char **user_data = (char **) evt->user_data;
+
+			if (*user_data == NULL) {
+				*user_data = calloc(cont_len + 1, sizeof(char));
+				if (!evt->user_data)
+					ESP_LOGE(TAG, "calloc() failed for response buffer");
+			}
+
+			if (evt->user_data) {
+				copy_len = MIN(evt->data_len, (cont_len - read_len));
+				if (copy_len) {
+					memcpy((*(char **) evt->user_data) + read_len,
+						evt->data, copy_len);
+					read_len += copy_len;
+				}
+
+				ESP_LOGD(TAG, "HTTP response size = %d bytes", read_len);
+			}
+			break;
+		case HTTP_EVENT_ON_FINISH:
+			read_len = 0;
+
+			ESP_LOGD(TAG, "HTTP_EVENT_ON_FINISH");
+			ESP_LOGD(TAG, "%s", *(char **) evt->user_data);
+			ESP_LOGD(TAG,
+				"response status=%d",
+				esp_http_client_get_status_code(evt->client));
+
+			break;
+		case HTTP_EVENT_DISCONNECTED:
+			int mbedtls_err = 0;
+			esp_err_t err;
+
+			ESP_LOGI(TAG, "HTTP_EVENT_DISCONNECTED");
+
+			err = esp_tls_get_and_clear_last_error(
+				(esp_tls_error_handle_t) evt->data,
+				&mbedtls_err,
+				NULL);
+
+			if (err != 0) {
+				ESP_LOGE(TAG, "Last esp error code: 0x%x", err);
+				ESP_LOGI(TAG, "Last mbedtls failure: 0x%x", mbedtls_err);
+			}
+
+			read_len = 0;
+			break;
+		default:
+			break;
+	}
+
+	return ESP_OK;
+}
+
+static inline int min(int a, int b) {
+	return a < b ? a : b;
+}
+
+static inline int max(int a, int b) {
+	return a > b ? a : b;
+}
+
+static inline int get_price_value(char **s, char *buf, int n) {
+	int i;
+
+	for (i = 0; **s && **s != '\n'; (*s)++) {
+		if (i < n - 1)
+			buf[i++] = **s;
+	}
+
+	buf[i] = '\0';
+	return (int)(atof(buf) * 100);
+}
+
+static inline void parse(char *s, struct stock_data *sd)
+{
+	int i;
+	const int n = 10;
+
+	char buf_t[n];
+	char buf_p[n];
+
+	sd->price_max = 0;
+	sd->price_min = INT_MAX;
+
+	for (i = 0; *s && *s != '\n'; s++) {
+		if (i < n - 1)
+			buf_t[i++] = *s;
+	}
+
+	buf_t[i] = '\0';
+
+	if (*s)
+		s++;
+
+	sd->price_ref = get_price_value(&s, buf_p, n);
+
+	if (*s)
+		s++;
+	
+	for (i = 0; *s && *s != '\n' && i < sd->prices_maxlen; i++) {
+		sd->prices[i] = get_price_value(&s, buf_p, n);
+		sd->price_min = min(sd->prices[i], sd->price_min);
+		sd->price_max = max(sd->prices[i], sd->price_max);
+
+		if (*s)
+			s++;
+	}
+
+	sd->prices_len = i;
+
+	if (!sd->price_ref)
+		sd->price_ref = sd->price_max + 1;
+
+	snprintf(sd->ticker, TICKER_LEN, "%s: %s", buf_t, buf_p);
+}
+
+void stock_get_data(struct stock_data *sd)
+{
+	esp_err_t rc;
+	char *buf = NULL;
+
+	esp_http_client_config_t conf = {
+		.url = CONFIG_STOCK_API_URL,
+		.is_async = true,
+		.timeout_ms = 5000,
+		.event_handler = http_evt_handler,
+		.disable_auto_redirect = true,
+		.auth_type = HTTP_AUTH_TYPE_BASIC,
+		.max_authorization_retries = -1
+	};
+
+	http_client = esp_http_client_init(&conf);
+	esp_http_client_set_user_data(http_client, &buf);	
+
+	for(;;) {
+		rc = esp_http_client_perform(http_client);
+		if (rc != ESP_ERR_HTTP_EAGAIN)
+			break;
+
+		vTaskDelay((TickType_t) 100 / portTICK_PERIOD_MS);
+	}
+
+	parse(buf, sd);
+
+	free(buf);
+	ESP_ERROR_CHECK(esp_http_client_cleanup(http_client));	
+	http_client = NULL;
+}
+