[Tarantool-patches] [PATCH v4 3/4] http: enrich httpc_request with curl error message buffer

[Ilya Kosarev <i.kosarev@tarantool.org>]

When processing curl request error code, we are collecting error
message using curl_easy_strerror. Now we are providing more info
in errmsg, which is obtained using curl_easy_setopt with
CURLOPT_ERRORBUFFER option. Test case to confirm it is added.

Closes #4578

@TarantoolBot document
Title: http: new field in client_object:request return table
Update the documentation for client_object:request method to reflect
new field errmsg in return table. It contains extended curl request
error message obtained using CURLOPT_ERRORBUFFER option.
See https://curl.haxx.se/libcurl/c/CURLOPT_ERRORBUFFER.html
---
 src/httpc.c                       | 1 +
 src/httpc.h                       | 5 +++++
 src/lua/httpc.c                   | 4 ++++
 test/app-tap/http_client.test.lua | 4 +++-
 4 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/httpc.c b/src/httpc.c
index 22b54d16a..b493a8498 100644
--- a/src/httpc.c
+++ b/src/httpc.c
@@ -398,6 +398,7 @@ httpc_execute(struct httpc_request *req, double timeout)
 	curl_easy_setopt(req->curl_request.easy, CURLOPT_HEADERDATA, (void *) req);
 	curl_easy_setopt(req->curl_request.easy, CURLOPT_PRIVATE, (void *) &req->curl_request);
 	curl_easy_setopt(req->curl_request.easy, CURLOPT_HTTPHEADER, req->headers);
+	curl_easy_setopt(req->curl_request.easy, CURLOPT_ERRORBUFFER, req->errmsg);
 
 	++env->stat.total_requests;
 
diff --git a/src/httpc.h b/src/httpc.h
index f710b3d13..145b59929 100644
--- a/src/httpc.h
+++ b/src/httpc.h
@@ -105,6 +105,11 @@ struct httpc_request {
 	int status;
 	/** Error message */
 	const char *reason;
+	/**
+	 * Buffer for error message obtained using
+	 * CURLOPT_ERRORBUFFER option.
+	 */
+        const char errmsg[CURL_ERROR_SIZE];
 	/** buffer of headers */
 	struct region resp_headers;
 	/** buffer of body */
diff --git a/src/lua/httpc.c b/src/lua/httpc.c
index 6ed4eb788..9fb8e4801 100644
--- a/src/lua/httpc.c
+++ b/src/lua/httpc.c
@@ -335,6 +335,10 @@ luaT_httpc_request(lua_State *L)
 	lua_pushstring(L, req->reason);
 	lua_settable(L, -3);
 
+	lua_pushstring(L, "errmsg");
+	lua_pushstring(L, req->errmsg);
+	lua_settable(L, -3);
+
 	size_t headers_len = region_used(&req->resp_headers);
 	if (headers_len > 0) {
 		char *headers = region_join(&req->resp_headers, headers_len);
diff --git a/test/app-tap/http_client.test.lua b/test/app-tap/http_client.test.lua
index b85b605cf..2fac80115 100755
--- a/test/app-tap/http_client.test.lua
+++ b/test/app-tap/http_client.test.lua
@@ -171,7 +171,7 @@ local function test_cancel_and_errinj(test, url, opts)
 end
 
 local function test_post_and_get(test, url, opts)
-    test:plan(21)
+    test:plan(23)
 
     local http = client.new()
     test:ok(http ~= nil, "client is created")
@@ -227,6 +227,7 @@ local function test_post_and_get(test, url, opts)
     r = responses.absent_get
     test:is(r.status, 500, "GET: absent method http code page exists")
     test:is(r.reason, 'Unknown', '500 - Unknown')
+    test:is(type(r.errmsg), 'string', 'check error message')
     test:is(r.body, "No such method", "GET: absent method right body")
 
     r = responses.empty_post
@@ -249,6 +250,7 @@ local function test_post_and_get(test, url, opts)
     r = responses.bad_get
     test:is(r.status, 404, "GET: http page not exists")
     test:is(r.reason, 'Unknown', '404 - Unknown')
+    test:is(type(r.errmsg), 'string', 'check error message')
     test:isnt(r.body:len(), 0, "GET: not empty body page not exists")
     test:ok(string.find(r.body, "Not Found"),
                 "GET: right body page not exists")
-- 
2.17.1