[PATCH] http-push: making HTTP push more robust and more user-friendly

["Grégoire Barbier" <gb@gbarbier.org>]

Fail when info/refs exists and is already locked (avoiding strange behaviour
and errors, and maybe avoiding some repository corruption).

Warn if the URL does not end with '/' (since 302 is not yet handled)

More explicit error message when the URL or password is not set correctly
(instead of "no DAV locking support").

DAV locking time of 1 minute instead of 10 minutes (avoid waiting 10 minutes
for a orphan lock to expire before anyone can do a push on the repo).

Signed-off-by: Grégoire Barbier <gb@gbarbier.org>
---
 http-push.c |   17 ++++++++++++++++-
 http.c      |   25 +++++++++++++++++++++++++
 http.h      |    1 +
 3 files changed, 42 insertions(+), 1 deletions(-)

diff --git a/http-push.c b/http-push.c
index 55d0c94..c005903 100644
--- a/http-push.c
+++ b/http-push.c
@@ -57,7 +57,7 @@ enum XML_Status {
 #define PROPFIND_ALL_REQUEST "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n<D:allprop/>\n</D:propfind>"
 #define LOCK_REQUEST "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:lockinfo xmlns:D=\"DAV:\">\n<D:lockscope><D:exclusive/></D:lockscope>\n<D:locktype><D:write/></D:locktype>\n<D:owner>\n<D:href>mailto:%s</D:href>\n</D:owner>\n</D:lockinfo>"
 
-#define LOCK_TIME 600
+#define LOCK_TIME 60
 #define LOCK_REFRESH 30
 
 /* bits #0-15 in revision.h */
@@ -2224,6 +2224,16 @@ int main(int argc, char **argv)
 
 	no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 
+	/* Verify connexion string (agains bad URLs or password errors) */
+	if (remote->url && remote->url[strlen(remote->url)-1] != '/') {
+		fprintf(stderr, "Warning: remote URL does not end with a '/' which often leads to problems\n");
+	}
+	if (!http_test_connection(remote->url)) {
+		fprintf(stderr, "Error: cannot access to remote URL (maybe malformed URL, network error or bad credentials)\n");
+		rc = 1;
+		goto cleanup;
+	}
+
 	/* Verify DAV compliance/lock support */
 	if (!locking_available()) {
 		fprintf(stderr, "Error: no DAV locking support on remote repo %s\n", remote->url);
@@ -2239,6 +2249,11 @@ int main(int argc, char **argv)
 		info_ref_lock = lock_remote("info/refs", LOCK_TIME);
 		if (info_ref_lock)
 			remote->can_update_info_refs = 1;
+		else {
+			fprintf(stderr, "Error: cannot lock existing info/refs\n");
+			rc = 1;
+			goto cleanup;
+		}
 	}
 	if (remote->has_info_packs)
 		fetch_indices();
diff --git a/http.c b/http.c
index d2c11ae..8b04ae9 100644
--- a/http.c
+++ b/http.c
@@ -634,3 +634,28 @@ int http_fetch_ref(const char *base, const char *ref, unsigned char *sha1)
 	free(url);
 	return ret;
 }
+
+int http_test_connection(const char *url)
+{
+	struct strbuf buffer = STRBUF_INIT;
+	struct active_request_slot *slot;
+	struct slot_results results;
+	int ret = 0;
+
+	slot = get_active_slot();
+	slot->results = &results;
+	curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
+	curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
+	curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
+	curl_easy_setopt(slot->curl, CURLOPT_URL, url);
+	if (start_active_slot(slot)) {
+		run_active_slot(slot);
+		if (results.curl_result == CURLE_OK)
+			ret = -1;
+		else
+			error("Cannot access to URL %s, return code %d", url, results.curl_result);
+	} else
+		error("Unable to start request");
+	strbuf_release(&buffer);
+	return ret;
+}
diff --git a/http.h b/http.h
index aeba930..b353007 100644
--- a/http.h
+++ b/http.h
@@ -77,6 +77,7 @@ extern void step_active_slots(void);
 
 extern void http_init(void);
 extern void http_cleanup(void);
+extern int http_test_connection(const char *url);
 
 extern int data_received;
 extern int active_requests;
-- 
1.5.3.6