Espressif ESP32-S2 User Manual

Chapter 2. API Reference
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/* Load server private key */
extern const unsigned char prvtkey_pem_start[] asm("_binary_prvtkey_pem_
,→start");
extern const unsigned char prvtkey_pem_end[] asm("_binary_prvtkey_pem_
,→end");
https_conf.prvtkey_pem = prvtkey_pem_start;
https_conf.prvtkey_len = prvtkey_pem_end - prvtkey_pem_start;
esp_local_ctrl_config_t config = {
.transport = ESP_LOCAL_CTRL_TRANSPORT_HTTPD,
.transport_config = {
.httpd = &https_conf
},
.proto_sec = {
.version = PROTOCOM_SEC0,
.custom_handle = NULL,
.pop = NULL,
},
.handlers = {
/* User defined handler functions */
.get_prop_values = get_property_values,
.set_prop_values = set_property_values,
.usr_ctx = NULL,
.usr_ctx_free_fn = NULL
},
/* Maximum number of properties that may be set */
.max_properties = 10
};
/* Start esp_local_ctrl service */
ESP_ERROR_CHECK(esp_local_ctrl_start(&config));
You may set security for transport in ESP local control using following options:
1. PROTOCOM_SEC1: specifies that end to end encryption is used.
2. PROTOCOM_SEC0: specifies that data will be exchanged as a plain text.
3. PROTOCOM_SEC_CUSTOM: you can define your own security requirement. Please note that you will also
have to provide custom_handle of type protocomm_security_t * in this context.
Creating a property
Now that we know how to start the esp_local_ctrl service, let’s add a property to it. Each property must have a
unique name (string), a type (e.g. enum), flags (bit fields) and size.
The size is to be kept 0, if we want our property value to be of variable length (e.g. if its a string or bytestream). For
fixed length property value data-types, like int, float, etc., setting the size field to the right value, helps esp_local_ctrl
to perform internal checks on arguments received with write requests.
The interpretation of type and flags fields is totally upto the application, hence they may be used as enumerations, bit-
fields, or even simple integers. One way is to use type values to classify properties, while flags to specify characteristics
of a property.
Here is an example property which is to function as a timestamp. It is assumed that the application defines
TYPE_TIMESTAMP and READONLY, which are used for setting the type and flags fields here.
/* Create a timestamp property */
esp_local_ctrl_prop_t timestamp = {
.name = "timestamp",
.type = TYPE_TIMESTAMP,
.size = sizeof(int32_t),
.flags = READONLY,
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Espressif ESP32-S2 Specifications

General

Brand	Espressif
Model	ESP32-S2
Category	Single board computers
Language	English