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/************* Restget C++ Program Source Code File (.CPP) *************/
/* Adapted from the sample program of the Casablanca tutorial. */
/* Copyright Olivier Bertrand 2019. */
/***********************************************************************/
#include <cpprest/filestream.h>
#include <cpprest/http_client.h>
using namespace utility::conversions; // String conversions utilities
using namespace web; // Common features like URIs.
using namespace web::http; // Common HTTP functionality
using namespace web::http::client; // HTTP client features
using namespace concurrency::streams; // Asynchronous streams
typedef const char* PCSZ;
extern "C" int restGetFile(char* m, bool xt, PCSZ http, PCSZ uri, PCSZ fn);
/***********************************************************************/
/* Make a local copy of the requested file. */
/***********************************************************************/
int restGetFile(char *m, bool xt, PCSZ http, PCSZ uri, PCSZ fn)
{
int rc = 0;
auto fileStream = std::make_shared<ostream>();
if (!http || !fn) {
//strcpy(g->Message, "Missing http or filename");
strcpy(m, "Missing http or filename");
return 2;
} // endif
if (xt)
fprintf(stderr, "restGetFile: fn=%s\n", fn);
// Open stream to output file.
pplx::task<void> requestTask = fstream::open_ostream(to_string_t(fn))
.then([=](ostream outFile) {
*fileStream= outFile;
if (xt)
fprintf(stderr, "Outfile isopen=%d\n", outFile.is_open());
// Create http_client to send the request.
http_client client(to_string_t(http));
if (uri) {
// Build request URI and start the request.
uri_builder builder(to_string_t(uri));
return client.request(methods::GET, builder.to_string());
} else
return client.request(methods::GET);
})
// Handle response headers arriving.
.then([=](http_response response) {
if (xt)
fprintf(stderr, "Received response status code:%u\n",
response.status_code());
// Write response body into the file.
return response.body().read_to_end(fileStream->streambuf());
})
// Close the file stream.
.then([=](size_t n) {
if (xt)
fprintf(stderr, "Return size=%zu\n", n);
return fileStream->close();
});
// Wait for all the outstanding I/O to complete and handle any exceptions
try {
if (xt)
fprintf(stderr, "Waiting\n");
requestTask.wait();
} catch (const std::exception &e) {
if (xt)
fprintf(stderr, "Error exception: %s\n", e.what());
sprintf(m, "Error exception: %s", e.what());
rc= 1;
} // end try/catch
if (xt)
fprintf(stderr, "restget done: rc=%d\n", rc);
return rc;
} // end of restGetFile
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