Added start of HTTP server (& data storage)

components/http_server/CMakeLists.txt

@@ -0,0 +1,4 @@
+idf_component_register(SRCS "http.c"
+  INCLUDE_DIRS "."
+  PRIV_REQUIRES dht22 wifi esp_http_server 
+)

components/http_server/Kconfig.projbuild

@@ -0,0 +1,14 @@
+menu "HTTP"
+#    config WIFI_SSID
+#        string "WiFi SSID"
+#        default "VM8094728"
+#        help
+#            SSID (network name) for the example to connect to.
+
+#    config WIFI_PASSWORD
+#        string "WiFi Password"
+#        default "tx3YrxvzMrbr"
+#        help
+#            WiFi password (WPA or WPA2) for the example to use.
+
+endmenu

components/http_server/http.c

@@ -0,0 +1,98 @@
+#include "http.h"
+#include "esp_sntp.h"
+#include "wifi.h"
+#include <math.h>
+#include <stdlib.h>
+#include "esp_log.h"
+#include "esp_http_server.h"
+
+// 2 Days worth of samples
+#define NUM_SAMPLES_TO_STORE (( 24  *   60 ) / 10 ) * 2
+
+typedef struct {
+  uint8_t myt_sec;   // 0 -> 61
+  uint8_t myt_min;   // 0 -> 59
+  uint8_t myt_hour;  // 0 -> 23
+  uint8_t myt_day;   // 1 -> 31
+  uint8_t myt_month; // 0 -> 11 !!
+  uint8_t myt_year;  // years since 1900
+} my_time;
+
+typedef struct {
+  deci_percent rh;
+  deci_degrees_c temp;
+  my_time time;
+} my_dht22_data;
+
+
+// I know this is asking for a race condition...
+static my_dht22_data *dht22_buffer = NULL;
+static int dht22_num = 0;
+
+my_time get_time() {
+  time_t epoch;
+  time(&epoch);
+  struct tm *timeinfo = localtime(&epoch);
+  my_time my_current_time;
+
+  // There must be a better way - I couldn't figure out how to do it
+  // nicely all at once
+  my_current_time.myt_sec = timeinfo->tm_sec;
+  // -5 to get the middle of the averaged window
+  my_current_time.myt_min = timeinfo->tm_min;
+  my_current_time.myt_hour = timeinfo->tm_hour;
+  my_current_time.myt_day = timeinfo->tm_mday;
+  my_current_time.myt_month = timeinfo->tm_mon;
+  my_current_time.myt_year = timeinfo->tm_year;
+  return my_current_time;
+}
+
+
+esp_err_t dht22_data_get_handler(httpd_req_t *req) {
+  char *resp;
+
+  size_t size_of_csv_line = strlen("YYYY:MM:DD HH:MM:SS,XXXX,YYYY\n");
+
+  resp = calloc(dht22_num, size_of_csv_line + 1);
+
+  for (int i = 0; i < dht22_num; i++) {
+    my_dht22_data d = dht22_buffer[i];
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-truncation"
+    snprintf(resp + (i * size_of_csv_line), size_of_csv_line,
+             "%04d:%02d:%02d %02d:%02d:%02d\t%04d\t%04d\n", d.time.myt_year,
+             d.time.myt_month, d.time.myt_day, d.time.myt_hour, d.time.myt_min,
+             d.time.myt_sec, d.rh, d.temp);
+#pragma GCC diagnostic pop
+  }
+  // shouldn't need to null terminate this becuase of calloc
+
+  httpd_resp_send(req, resp, HTTPD_RESP_USE_STRLEN);
+  return ESP_OK;
+}
+
+/* URI handler structure for GET /uri */
+httpd_uri_t dht22_data_get = {
+    .uri      = "/dht22.csv",
+    .method   = HTTP_GET,
+    .handler  = dht22_data_get_handler,
+    .user_ctx = NULL
+};
+
+void init_dht22_data() {
+  dht22_buffer = malloc(NUM_SAMPLES_TO_STORE * sizeof(my_dht22_data));
+  // register an http endpoint thingy probably?
+}
+
+void add_dht22_data(float rh, float temp) {
+  if (dht22_buffer == NULL) {
+    return;
+  }
+  my_dht22_data dht22_data;
+  dht22_data.time = get_time();
+  dht22_data.time.myt_min -= 5;
+  dht22_data.temp = round(temp);
+  dht22_data.rh = round(rh);
+  dht22_buffer[dht22_num] = dht22_data;
+  dht22_num++;
+}

components/http_server/http.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include "dht22.h"
+
+void init_dht22_data();
+
+// This function presumes we've got a 10 minute average here
+//  - could think about abstracting the average out into this
+//  function maybe. Something for the future!
+void add_dht22_data(float rh, float temp);

main/main.c

@@ -6,14 +6,15 @@
 
 #include "dht22.h"
 #include "esp_log.h"
-#include "esp_sntp.h"
 #include "freertos/FreeRTOS.h"
 #include "freertos/projdefs.h"
 #include "freertos/task.h"
+#include "http.h"
 #include "nvs_flash.h"
 #include "portmacro.h"
 #include "sdkconfig.h"
 #include "wifi.h"
+#include "http.h"
 #include <inttypes.h>
 #include <stdbool.h>
 #include <stdint.h>
@@ -29,15 +30,6 @@ static TaskHandle_t dht22_handle = NULL;
 static TaskHandle_t pms5003_handle = NULL;
 static TaskHandle_t ds18b20_handle = NULL;
 
-typedef struct {
-  uint8_t myt_sec;   // 0 -> 61
-  uint8_t myt_min;   // 0 -> 69
-  uint8_t myt_hour;  // 0 -> 23
-  uint8_t myt_day;   // 1 -> 31
-  uint8_t myt_month; // 0 -> 11 !!
-  uint8_t myt_year;  // years since 1900
-} my_time;
-
 #ifdef CONFIG_DS18B20_ENABLED
 #include "ds18b20.h"
 
@@ -65,13 +57,8 @@ void read_from_pms5003() {
 #ifdef CONFIG_DHT22_ENABLED
 #include "dht22.h"
 
-typedef struct {
-  deci_percent rh;
-  deci_degrees_c temp;
-  my_time time;
-} my_dht22_data;
-
-my_dht22_data latest_datapoint;
+deci_percent dht22_rh;
+deci_degrees_c dht22_temp;
 
 void read_from_dht22() {
   // From datasheet:
@@ -81,33 +68,32 @@ void read_from_dht22() {
   uint32_t num_samples_last_ten_mins = 0;
   float relative_humidity_tmp;
   float temperature_tmp;
-  my_dht22_data ten_minute_average;
 
   while (run_dht) {
     int ret = dht22_read();
     if (ret != DHT22_OK) {
       dht22_handle_error(ret);
     } else {
-      latest_datapoint.temp = dht22_temperature();
-      latest_datapoint.rh = dht22_relative_humidity();
+      dht22_temp = dht22_temperature();
+      dht22_rh = dht22_relative_humidity();
       ESP_LOGI(TAG,
-               "Sucesfully obtained DHT22 data (temp: %"PRIi16" rh: %"PRIu16")",
-               latest_datapoint.temp, latest_datapoint.rh);
+               "Sucesfully obtained DHT22 data (temp: %" PRIi16 " rh: %" PRIu16
+               ")",
+               dht22_temp, dht22_rh);
 
       // No point collecting rolling average if we don't know what the time is
       if (has_ntp_time_obtained_once()) {
         if (num_samples_last_ten_mins == 0) {
-          relative_humidity_tmp = latest_datapoint.rh;
-          temperature_tmp = latest_datapoint.temp;
+          relative_humidity_tmp = dht22_rh;
+          temperature_tmp = dht22_temp;
         } else {
-          relative_humidity_tmp +=
-              ((float)latest_datapoint.rh - relative_humidity_tmp) /
+          relative_humidity_tmp += ((float)dht22_rh - relative_humidity_tmp) /
                                    ((float)num_samples_last_ten_mins + 1.0);
-          temperature_tmp += ((float)latest_datapoint.temp - temperature_tmp) /
+          temperature_tmp += ((float)dht22_temp - temperature_tmp) /
                              ((float)num_samples_last_ten_mins + 1.0);
         }
         num_samples_last_ten_mins += 1;
-        ESP_LOGI(TAG, "latest_datapoint.temp: %" PRIi16, latest_datapoint.temp);
+        ESP_LOGI(TAG, "latest_datapoint.temp: %" PRIi16, dht22_temp);
         ESP_LOGI(TAG, "ten_minute_average.temp: %f, num_samples: %" PRIu32,
                  temperature_tmp, num_samples_last_ten_mins);
 
@@ -119,30 +105,8 @@ void read_from_dht22() {
                    temperature_tmp);
           num_samples_last_ten_mins = 0;
 
-          time_t epoch;
-          time(&epoch);
-          struct tm *timeinfo = localtime(&epoch);
+          add_dht22_data(relative_humidity_tmp, temperature_tmp);
 
-          // There must be a better way - I couldn't figure out how to do it
-          // nicely all at once
-          ten_minute_average.time.myt_sec = timeinfo->tm_sec;
-          // -5 to get the middle of the averaged window
-          ten_minute_average.time.myt_min = timeinfo->tm_min - 5;
-          ten_minute_average.time.myt_hour = timeinfo->tm_hour;
-          ten_minute_average.time.myt_day = timeinfo->tm_mday;
-          ten_minute_average.time.myt_month = timeinfo->tm_mon;
-          ten_minute_average.time.myt_year = timeinfo->tm_year;
-
-          // TODO: Consider rounding this number - although, .1 of a degree C...
-          //  no one is going to miss that. Probably the calculation require to
-          //  do the rounding would affect the temperature that much anyways
-          //  haha
-          ten_minute_average.temp = temperature_tmp;
-          ten_minute_average.rh = relative_humidity_tmp;
-          ESP_LOGW(TAG, "ten_min_avg.temp %" PRIi16 ", .rh %" PRIu16,
-                   ten_minute_average.temp, ten_minute_average.rh);
-
-          // TODO: Write the data out somewhere - into RAM maybe
           // TODO: maybe push the data somewhere - or put a flag up that data
           // can be pushed
           //  ^ could do a cute Semaphore thingy here - I don't think I've
@@ -165,6 +129,7 @@ void app_main(void) {
   ESP_ERROR_CHECK(ret);
 
 #ifdef CONFIG_DHT22_ENABLED
+  init_dht22_data();
   xTaskCreate(read_from_dht22, "DHT22",
               4 * 1024, // honestly I have _no_ idea
               NULL,
@@ -190,5 +155,5 @@ void app_main(void) {
               5, // no idea either
               &ds18b20_handle);
 #endif /* CONFIG DS18B20_ENABLED */
-  // start_wifi();
+  start_wifi();
 }