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).
Committer:
Jan Jongboom
Date:
Wed Feb 15 21:57:31 2017 +0100
Revision:
0:85fdc69bc10c
Child:
3:0f5859a9e3de
Initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Jan Jongboom 0:85fdc69bc10c 1 #include "select-demo.h"
Jan Jongboom 0:85fdc69bc10c 2
Jan Jongboom 0:85fdc69bc10c 3 #if DEMO == DEMO_HTTP
Jan Jongboom 0:85fdc69bc10c 4
Jan Jongboom 0:85fdc69bc10c 5 #include "mbed.h"
Jan Jongboom 0:85fdc69bc10c 6 #include "easy-connect.h"
Jan Jongboom 0:85fdc69bc10c 7 #include "http_request.h"
Jan Jongboom 0:85fdc69bc10c 8
Jan Jongboom 0:85fdc69bc10c 9 Serial pc(USBTX, USBRX);
Jan Jongboom 0:85fdc69bc10c 10
Jan Jongboom 0:85fdc69bc10c 11 void dump_response(HttpResponse* res) {
Jan Jongboom 0:85fdc69bc10c 12 printf("Status: %d - %s\n", res->get_status_code(), res->get_status_message().c_str());
Jan Jongboom 0:85fdc69bc10c 13
Jan Jongboom 0:85fdc69bc10c 14 printf("Headers:\n");
Jan Jongboom 0:85fdc69bc10c 15 for (size_t ix = 0; ix < res->get_headers_length(); ix++) {
Jan Jongboom 0:85fdc69bc10c 16 printf("\t%s: %s\n", res->get_headers_fields()[ix].c_str(), res->get_headers_values()[ix].c_str());
Jan Jongboom 0:85fdc69bc10c 17 }
Jan Jongboom 0:85fdc69bc10c 18 printf("\nBody:\n\n%s\n", res->get_body().c_str());
Jan Jongboom 0:85fdc69bc10c 19 }
Jan Jongboom 0:85fdc69bc10c 20
Jan Jongboom 0:85fdc69bc10c 21 int main() {
Jan Jongboom 0:85fdc69bc10c 22 pc.baud(115200);
Jan Jongboom 0:85fdc69bc10c 23 // Connect to the network (see mbed_app.json for the connectivity method used)
Jan Jongboom 0:85fdc69bc10c 24 NetworkInterface *network = easy_connect(true);
Jan Jongboom 0:85fdc69bc10c 25 if (!network) {
Jan Jongboom 0:85fdc69bc10c 26 printf("Cannot connect to the network, see serial output");
Jan Jongboom 0:85fdc69bc10c 27 return 1;
Jan Jongboom 0:85fdc69bc10c 28 }
Jan Jongboom 0:85fdc69bc10c 29
Jan Jongboom 0:85fdc69bc10c 30 // Do a GET request to httpbin.org
Jan Jongboom 0:85fdc69bc10c 31 HttpRequest get_req(network, HTTP_GET, "http://httpbin.org/status/418");
Jan Jongboom 0:85fdc69bc10c 32
Jan Jongboom 0:85fdc69bc10c 33 // By default the body is automatically parsed and stored in a string, this is memory heavy.
Jan Jongboom 0:85fdc69bc10c 34 // To receive chunked response, pass in a callback as third parameter to 'send'.
Jan Jongboom 0:85fdc69bc10c 35 HttpResponse* get_res = get_req.send();
Jan Jongboom 0:85fdc69bc10c 36 if (!get_res) {
Jan Jongboom 0:85fdc69bc10c 37 printf("HttpRequest failed (error code %d)\n", get_req.get_error());
Jan Jongboom 0:85fdc69bc10c 38 return 1;
Jan Jongboom 0:85fdc69bc10c 39 }
Jan Jongboom 0:85fdc69bc10c 40
Jan Jongboom 0:85fdc69bc10c 41 printf("\n----- HTTP GET response -----\n");
Jan Jongboom 0:85fdc69bc10c 42 dump_response(get_res);
Jan Jongboom 0:85fdc69bc10c 43
Jan Jongboom 0:85fdc69bc10c 44 delete get_res;
Jan Jongboom 0:85fdc69bc10c 45
Jan Jongboom 0:85fdc69bc10c 46 // POST request to httpbin.org
Jan Jongboom 0:85fdc69bc10c 47 HttpRequest post_req(network, HTTP_POST, "http://httpbin.org/post");
Jan Jongboom 0:85fdc69bc10c 48 post_req.set_header("Content-Type", "application/json");
Jan Jongboom 0:85fdc69bc10c 49
Jan Jongboom 0:85fdc69bc10c 50 const char body[] = "{\"hello\":\"world\"}";
Jan Jongboom 0:85fdc69bc10c 51
Jan Jongboom 0:85fdc69bc10c 52 HttpResponse* post_res = post_req.send(body, strlen(body));
Jan Jongboom 0:85fdc69bc10c 53 if (!post_res) {
Jan Jongboom 0:85fdc69bc10c 54 printf("HttpRequest failed (error code %d)\n", post_req.get_error());
Jan Jongboom 0:85fdc69bc10c 55 return 1;
Jan Jongboom 0:85fdc69bc10c 56 }
Jan Jongboom 0:85fdc69bc10c 57
Jan Jongboom 0:85fdc69bc10c 58 printf("\n----- HTTP POST response -----\n");
Jan Jongboom 0:85fdc69bc10c 59 dump_response(post_res);
Jan Jongboom 0:85fdc69bc10c 60
Jan Jongboom 0:85fdc69bc10c 61 delete post_res;
Jan Jongboom 0:85fdc69bc10c 62
Jan Jongboom 0:85fdc69bc10c 63
Jan Jongboom 0:85fdc69bc10c 64 Thread::wait(osWaitForever);
Jan Jongboom 0:85fdc69bc10c 65 }
Jan Jongboom 0:85fdc69bc10c 66
Jan Jongboom 0:85fdc69bc10c 67 #endif