Re: [Libguestfs] [PATCH nbdkit v2 2/2] tests: Test retry-request + curl in a realistic mirroring situation

Test the new nbdkit-retry-request-filter with the curl plugin. I have modified our test webserver so it provides a magical "/mirror" path which acts somewhat like a download mirror with occasional broken redirects. Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2013000 --- tests/Makefile.am | 24 ++++ tests/test-retry-request-mirror.c | 130 ++++++++++++++++++++ tests/web-server.c | 197 +++++++++++++++++++++++++++--- .gitignore | 1 + 4 files changed, 337 insertions(+), 15 deletions(-)

diff --git a/tests/Makefile.am b/tests/Makefile.am index 9a1485a6c..b8a3a654c 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -1701,6 +1701,30 @@ EXTRA_DIST += \ test-retry-request.sh \ $(NULL) +LIBNBD_TESTS += test-retry-request-mirror + +test_retry_request_mirror_SOURCES = \ + test-retry-request-mirror.c \ + web-server.c \ + web-server.h \ + test.h \ + $(NULL) +test_retry_request_mirror_CPPFLAGS = \ + -I$(top_srcdir)/common/utils +test_retry_request_mirror_CFLAGS = \ + $(WARNINGS_CFLAGS) \ + $(PTHREAD_CFLAGS) \ + $(LIBNBD_CFLAGS) \ + $(NULL) +test_retry_request_mirror_LDFLAGS = \ + $(top_builddir)/common/utils/libutils.la \ + $(PTHREAD_LIBS) \ + $(NULL) +test_retry_request_mirror_LDADD = \ + libtest.la \ + $(LIBNBD_LIBS) \ + $(NULL) + # swab filter test. TESTS += \ test-swab-8.sh \ diff --git a/tests/test-retry-request-mirror.c b/tests/test-retry-request-mirror.c new file mode 100644 index 000000000..861e2e0e5 --- /dev/null +++ b/tests/test-retry-request-mirror.c @@ -0,0 +1,130 @@ +/* nbdkit + * Copyright (C) 2013-2021 Red Hat Inc. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * * Neither the name of Red Hat nor the names of its contributors may be + * used to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A + * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +/* This is a test of recovering from broken redirects to a mirror + * service. See the following bug for background: + * https://bugzilla.redhat.com/show_bug.cgi?id=2013000 + */ + +#include <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <stdbool.h> +#include <stdint.h> +#include <inttypes.h> +#include <string.h> +#include <unistd.h> + +#include <libnbd.h> + +#include "cleanup.h" +#include "web-server.h" + +#include "test.h" + +int +main (int argc, char *argv[]) +{ + const char *sockpath; + struct nbd_handle *nbd; + CLEANUP_FREE char *usp_param = NULL; + char buf[512]; + int state, i; + +#ifndef HAVE_CURLOPT_UNIX_SOCKET_PATH + fprintf (stderr, "%s: curl does not support CURLOPT_UNIX_SOCKET_PATH\n", + argv[0]); + exit (77); +#endif + + sockpath = web_server ("disk", NULL); + if (sockpath == NULL) { + fprintf (stderr, "%s: could not start web server thread\n", argv[0]); + exit (EXIT_FAILURE); + } + + /* Start nbdkit. */ + if (asprintf (&usp_param, "unix-socket-path=%s", sockpath) == -1) { + perror ("asprintf"); + exit (EXIT_FAILURE);

+ } + if (test_start_nbdkit ("--filter=retry-request", + "curl", usp_param, "http://localhost/mirror", + "retry-request-delay=1", + NULL) == -1) + exit (EXIT_FAILURE); + + nbd = nbd_create (); + if (nbd == NULL) { + nbd_error: + fprintf (stderr, "%s: %s\n", argv[0], nbd_get_error ()); + exit (EXIT_FAILURE); + }

+ + if (nbd_connect_unix (nbd, sock /* NBD socket */) == -1) + goto nbd_error; + + /* The way the test works is we fetch the magic "/mirror" path (see + * web-server.c). This redirects to /mirror1, /mirror2, /mirror3 + * round robin on each request. /mirror1 returns all 1's, /mirror2 + * returns all 2's, and /mirror3 returns a 404 error. The 404 error + * should be transparently skipped by the filter, so we should see + * alternating 1's and 2's buffers. + */ + if (nbd_pread (nbd, buf, sizeof buf, 0, 0) == -1) + goto nbd_error; + + if (buf[0] == 1 && buf[1] == 1 && buf[511] == 1) + state = 2; + else if (buf[0] == 2 && buf[1] == 2 && buf[511] == 2) + state = 1; + else { + fprintf (stderr, "%s: unexpected start state\n", argv[0]); + exit (EXIT_FAILURE); + } + + for (i = 0; i < 10; ++i) { + if (nbd_pread (nbd, buf, sizeof buf, 0, 0) == -1) + goto nbd_error; + if (buf[0] != state || buf[1] != state || buf[511] != state) { + fprintf (stderr, "%s: unexpected state\n", argv[0]); + exit (EXIT_FAILURE); + } + state++; + if (state == 3) + state = 1; + } + + nbd_close (nbd); + exit (EXIT_SUCCESS); +} diff --git a/tests/web-server.c b/tests/web-server.c index ac44d16b2..07a2ec398 100644 --- a/tests/web-server.c +++ b/tests/web-server.c @@ -57,6 +57,8 @@ #define SOCK_CLOEXEC 0 #endif +enum method { HEAD, GET }; + static char tmpdir[] = "/tmp/wsXXXXXX"; static char sockpath[] = "............./sock"; static int listen_sock = -1; @@ -67,7 +69,12 @@ static check_request_t check_request; static void *start_web_server (void *arg); static void handle_requests (int s); -static void handle_request (int s, bool headers_only); +static void handle_file_request (int s, enum method method); +static void handle_mirror_redirect_request (int s); +static void handle_mirror_data_request (int s, enum method method, char byte); +static void send_404_not_found (int s); +static void send_405_method_not_allowed (int s); +static void send_500_internal_server_error (int s); static void xwrite (int s, const char *buf, size_t len); static void xpread (char *buf, size_t count, off_t offset); @@ -177,12 +184,15 @@ start_web_server (void *arg) static void handle_requests (int s) { - size_t r, n, sz; bool eof = false; fprintf (stderr, "web server: accepted connection\n"); while (!eof) { + size_t r, n, sz; + enum method method; + char path[128]; + /* Read request until we see "\r\n\r\n" (end of headers) or EOF. */ n = 0; for (;;) { @@ -214,30 +224,73 @@ handle_requests (int s) /* Call the optional user function to check the request. */ if (check_request) check_request (request); - /* HEAD or GET request? */ - if (strncmp (request, "HEAD ", 5) == 0) - handle_request (s, true); - else if (strncmp (request, "GET ", 4) == 0) - handle_request (s, false); + /* Get the method and path fields from the first line. */ + if (strncmp (request, "HEAD ", 5) == 0) { + method = HEAD; + n = strcspn (&request[5], " \n\t"); + if (n >= sizeof path) { + send_500_internal_server_error (s); + eof = true; + break; + } + memcpy (path, &request[5], n); + path[n] = '\0'; + } + else if (strncmp (request, "GET ", 4) == 0) { + method = GET; + n = strcspn (&request[4], " \n\t"); + if (n >= sizeof path) { + send_500_internal_server_error (s); + eof = true; + break; + } + memcpy (path, &request[4], n); + path[n] = '\0'; + } else { - /* Return 405 Method Not Allowed. */ - const char response[] = - "HTTP/1.1 405 Method Not Allowed\r\n" - "Content-Length: 0\r\n" - "Connection: close\r\n" - "\r\n"; - xwrite (s, response, strlen (response)); + send_405_method_not_allowed (s); eof = true; break; } + + fprintf (stderr, "web server: requested path: %s\n", path); + + /* For testing retry-request + curl: + * /mirror redirects round-robin to /mirror1, /mirror2, /mirror3 + * /mirror1 returns a file of \x01 bytes + * /mirror2 returns a file of \x02 bytes + * /mirror3 returns 404 errors + * Anything else returns a 500 error + */ + if (strcmp (path, "/mirror") == 0) + handle_mirror_redirect_request (s); + else if (strcmp (path, "/mirror1") == 0) + handle_mirror_data_request (s, method, 1); + else if (strcmp (path, "/mirror2") == 0) + handle_mirror_data_request (s, method, 2); + else if (strcmp (path, "/mirror3") == 0) { + send_404_not_found (s); + eof = true; + } + else if (strncmp (path, "/mirror", 7) == 0) { + send_500_internal_server_error (s); + eof = true; + } + + /* Otherwise it's a regular file request. 'path' is ignored, we + * only serve a single file passed to web_server(). + */ + else + handle_file_request (s, method); } close (s); } static void -handle_request (int s, bool headers_only) +handle_file_request (int s, enum method method) { + const bool headers_only = method == HEAD; uint64_t offset, length, end; const char *p; const char response1_ok[] = "HTTP/1.1 200 OK\r\n"; @@ -295,6 +348,120 @@ handle_request (int s, bool headers_only) free (data); } +/* Request for /mirror */ +static void +handle_mirror_redirect_request (int s) +{ + static char rr = '1'; /* round robin '1', '2', '3' */ + /* Note we send 302 (temporary redirect), same as Fedora's mirrorservice. */ + const char found[] = "HTTP/1.1 302 Found\r\nContent-Length: 0\r\n"; + char location[] = "Location: /mirrorX\r\n"; + const char eol[] = "\r\n"; + + location[17] = rr; + rr++; + if (rr == '4') + rr = '1'; + + xwrite (s, found, strlen (found)); + xwrite (s, location, strlen (location)); + xwrite (s, eol, strlen (eol)); +} + +static void +handle_mirror_data_request (int s, enum method method, char byte) +{ + const bool headers_only = method == HEAD; + uint64_t offset, length, end; + const char *p; + const char response1_ok[] = "HTTP/1.1 200 OK\r\n"; + const char response1_partial[] = "HTTP/1.1 206 Partial Content\r\n"; + const char response2[] = + "Accept-rANGES: bytes\r\n" /* See RHBZ#1837337 */ + "Connection: keep-alive\r\n" + "Content-Type: application/octet-stream\r\n"; + char response3[64]; + const char response4[] = "\r\n"; + char *data; + + /* If there's no Range request header then send the full size as the + * content-length. + */ + p = strcasestr (request, "\r\nRange: bytes="); + if (p == NULL) { + offset = 0; + length = statbuf.st_size; + xwrite (s, response1_ok, strlen (response1_ok)); + } + else { + p += 15; + if (sscanf (p, "%" SCNu64 "-%" SCNu64, &offset, &end) != 2) { + fprintf (stderr, "web server: could not parse " + "range request from curl client\n"); + exit (EXIT_FAILURE); + } + /* Unclear but "Range: bytes=0-4" means bytes 0-3. '4' is the + * byte beyond the end of the range. + */ + length = end - offset; + xwrite (s, response1_partial, strlen (response1_partial)); + } + + xwrite (s, response2, strlen (response2)); + snprintf (response3, sizeof response3, + "Content-Length: %" PRIu64 "\r\n", length); + xwrite (s, response3, strlen (response3)); + xwrite (s, response4, strlen (response4)); + + if (headers_only) + return; + + /* Send the file content. */ + data = malloc (length); + if (data == NULL) { + perror ("malloc"); + exit (EXIT_FAILURE); + } + + memset (data, byte, length); + xwrite (s, data, length); + + free (data); +} + +static void +send_404_not_found (int s) +{ + const char response[] = + "HTTP/1.1 404 Not Found\r\n" + "Content-Length: 0\r\n" + "Connection: close\r\n" + "\r\n"; + xwrite (s, response, strlen (response)); +} + +static void +send_405_method_not_allowed (int s) +{ + const char response[] = + "HTTP/1.1 405 Method Not Allowed\r\n" + "Content-Length: 0\r\n" + "Connection: close\r\n" + "\r\n"; + xwrite (s, response, strlen (response)); +} + +static void +send_500_internal_server_error (int s) +{ + const char response[] = + "HTTP/1.1 500 Internal Server Error\r\n" + "Content-Length: 0\r\n" + "Connection: close\r\n" + "\r\n"; + xwrite (s, response, strlen (response)); +} + static void xwrite (int s, const char *buf, size_t len) { diff --git a/.gitignore b/.gitignore index 847b72dd6..e7b07d510 100644 --- a/.gitignore +++ b/.gitignore @@ -155,6 +155,7 @@ plugins/*/*.3 /tests/test-python /tests/test-random /tests/test-readahead +/tests/test-retry-request-mirror /tests/test-ruby /tests/test-S3/boto3/__pycache__/ /tests/test-shell