sandbox / Mbed OS http-example

HTTP and HTTPS example application for Mbed OS 5

Dependencies:   mbed-http

This application demonstrates how to make HTTP and HTTPS requests and parse the response from Mbed OS 5.

It consists of six example applications, which you can select in source/select-demo.h:

Response parsing is done through nodejs/http-parser.

Note: HTTPS requests do not work on targets with less than 128K of RAM due to the size of the TLS handshake. For more background see mbed-http.

To build

  1. If you're using WiFi, specify the credentials in mbed_app.json.
  2. Build the project in the online compiler or using Mbed CLI.
  3. Flash the project to your development board.
  4. Attach a serial monitor to your board to see the debug messages.

Defining the network interface

This application uses the on-board network interface for your board. If you use an external network interface (f.e. a WiFi module) you need to add the driver to this project. Then, open network-helper.h and specify which network driver to use.

More information is in the Mbed OS documentation under IP Networking.

Entropy (or lack thereof)

On all platforms that do not have the TRNG feature, the application is compiled without TLS entropy sources. This means that your code is inherently unsafe and should not be deployed to any production systems. To enable entropy, remove the MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES and MBEDTLS_TEST_NULL_ENTROPY macros from mbed_app.json.

Flash size

Default flash size for HTTPS is very large, as the application is loading the default Mbed TLS configuration. To use a more optimized version, you can disable unused cypher suites and other Mbed TLS features with a custom configuration file. Create a new configuration file, then add in mbed_app.json:

"MBEDTLS_CONFIG_FILE=\"mbedtls_config.h\""

to the macros array.

Running tests

You can run the integration tests from this project via Mbed CLI.

  1. In select-demo.h set the DEMO macro to DEMO_TESTS.
  2. Set your WiFi credentials in mbed_app.json.
  3. Then run the tests via: 

$ mbed test -v -n mbed-http-tests-tests-*

Tested on

  • K64F with Ethernet.
  • NUCLEO_F411RE with ESP8266 (not working on Mbed OS 5.12+)
  • ODIN-W2 with WiFi.
  • K64F with Atmel 6LoWPAN shield.
  • DISCO-L475VG-IOT01A with WiFi (requires the wifi-ism43362 driver).

source/main-http-ipv6.cpp@35:4b847971db1b, 2019-01-04 (annotated)

Committer:
Jan Jongboom
Date:
Fri Jan 04 13:32:26 2019 +0100
Revision:
35:4b847971db1b
Parent:
31:66704f6f17c5 
Update to Mbed OS 5.11

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Jan Jongboom 24:9faf23bbfb7f 1 #include "select-demo.h"
Jan Jongboom 24:9faf23bbfb7f 2
Jan Jongboom 24:9faf23bbfb7f 3 #if DEMO == DEMO_HTTP_IPV6
Jan Jongboom 24:9faf23bbfb7f 4
Jan Jongboom 24:9faf23bbfb7f 5 #include "mbed.h"
Jan Jongboom 31:66704f6f17c5 6 #include "network-helper.h"
Jan Jongboom 24:9faf23bbfb7f 7 #include "http_request.h"
Jan Jongboom 24:9faf23bbfb7f 8
Jan Jongboom 24:9faf23bbfb7f 9 void dump_response(HttpResponse* res) {
Jan Jongboom 24:9faf23bbfb7f 10 printf("Status: %d - %s\n", res->get_status_code(), res->get_status_message().c_str());
Jan Jongboom 24:9faf23bbfb7f 11
Jan Jongboom 24:9faf23bbfb7f 12 printf("Headers:\n");
Jan Jongboom 24:9faf23bbfb7f 13 for (size_t ix = 0; ix < res->get_headers_length(); ix++) {
Jan Jongboom 24:9faf23bbfb7f 14 printf("\t%s: %s\n", res->get_headers_fields()[ix]->c_str(), res->get_headers_values()[ix]->c_str());
Jan Jongboom 24:9faf23bbfb7f 15 }
Jan Jongboom 24:9faf23bbfb7f 16 printf("\nBody (%d bytes):\n\n%s\n", res->get_body_length(), res->get_body_as_string().c_str());
Jan Jongboom 24:9faf23bbfb7f 17 }
Jan Jongboom 24:9faf23bbfb7f 18
Jan Jongboom 24:9faf23bbfb7f 19 int main() {
Jan Jongboom 30:4825e4f38844 20 NetworkInterface* network = connect_to_default_network_interface();
Jan Jongboom 24:9faf23bbfb7f 21 if (!network) {
Jan Jongboom 30:4825e4f38844 22 printf("Cannot connect to the network, see serial output\n");
Jan Jongboom 24:9faf23bbfb7f 23 return 1;
Jan Jongboom 24:9faf23bbfb7f 24 }
Jan Jongboom 24:9faf23bbfb7f 25
Jan Jongboom 24:9faf23bbfb7f 26 // Do a GET request to icanhazip.com which returns the public IPv6 address for the device
Jan Jongboom 24:9faf23bbfb7f 27 // This page is only accessible over IPv6
Jan Jongboom 24:9faf23bbfb7f 28 {
Jan Jongboom 24:9faf23bbfb7f 29 // By default the body is automatically parsed and stored in a buffer, this is memory heavy.
Jan Jongboom 24:9faf23bbfb7f 30 // To receive chunked response, pass in a callback as last parameter to the constructor.
Jan Jongboom 24:9faf23bbfb7f 31 HttpRequest* get_req = new HttpRequest(network, HTTP_GET, "http://ipv6.icanhazip.com");
Jan Jongboom 24:9faf23bbfb7f 32
Jan Jongboom 24:9faf23bbfb7f 33 HttpResponse* get_res = get_req->send();
Jan Jongboom 24:9faf23bbfb7f 34 if (!get_res) {
Jan Jongboom 24:9faf23bbfb7f 35 printf("HttpRequest failed (error code %d)\n", get_req->get_error());
Jan Jongboom 24:9faf23bbfb7f 36 return 1;
Jan Jongboom 24:9faf23bbfb7f 37 }
Jan Jongboom 24:9faf23bbfb7f 38
Jan Jongboom 24:9faf23bbfb7f 39 printf("\n----- HTTP GET response -----\n");
Jan Jongboom 24:9faf23bbfb7f 40 dump_response(get_res);
Jan Jongboom 24:9faf23bbfb7f 41
Jan Jongboom 24:9faf23bbfb7f 42 delete get_req;
Jan Jongboom 24:9faf23bbfb7f 43 }
Jan Jongboom 24:9faf23bbfb7f 44
Jan Jongboom 28:9bccd981a393 45 wait(osWaitForever);
Jan Jongboom 24:9faf23bbfb7f 46 }
Jan Jongboom 24:9faf23bbfb7f 47
Jan Jongboom 24:9faf23bbfb7f 48 #endif