From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Kirill Shcherbatov Subject: [PATCH v6 4/4] lib: introduce json_path_cmp, json_path_validate Date: Thu, 6 Dec 2018 11:42:31 +0300 Message-Id: <7e8a84a863de29269e0731f3dcff2df90ed6813e.1544084229.git.kshcherbatov@tarantool.org> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: tarantool-patches@freelists.org, vdavydov.dev@gmail.com Cc: kostja@tarantool.org, Kirill Shcherbatov List-ID: Introduced json_path_validate routine to ensure user-defined JSON path is valid. This will be required to raise an error if an incorrect user-defined jason-path is detected. Introduced json_path_cmp routine to compare JSON paths that may have different representation. Note that: - in case of paths that have same token-sequence prefix, the path having more tokens is assumed to be greater - both paths to compare should be valid Needed for #1012 --- src/lib/json/json.c | 29 +++++++++++++++++++++++++++++ src/lib/json/json.h | 28 ++++++++++++++++++++++++++++ test/unit/json_path.c | 37 ++++++++++++++++++++++++++++++++++++- test/unit/json_path.result | 13 ++++++++++++- 4 files changed, 105 insertions(+), 2 deletions(-) diff --git a/src/lib/json/json.c b/src/lib/json/json.c index 65169b047..5586e59fc 100644 --- a/src/lib/json/json.c +++ b/src/lib/json/json.c @@ -500,3 +500,32 @@ json_tree_postorder_next(struct json_token *root, struct json_token *pos) return json_tree_leftmost(next); return pos->parent; } + +int +json_path_cmp(const char *a, uint32_t a_len, const char *b, uint32_t b_len, + uint32_t index_base) +{ + struct json_lexer lexer_a, lexer_b; + json_lexer_create(&lexer_a, a, a_len, index_base); + json_lexer_create(&lexer_b, b, b_len, index_base); + struct json_token token_a, token_b; + token_a.parent = NULL; + token_b.parent = NULL; + int rc_a, rc_b; + while ((rc_a = json_lexer_next_token(&lexer_a, &token_a)) == 0 && + (rc_b = json_lexer_next_token(&lexer_b, &token_b)) == 0 && + token_a.type != JSON_TOKEN_END && + token_b.type != JSON_TOKEN_END) { + int rc = json_token_cmp(&token_a, &token_b); + if (rc != 0) + return rc; + } + /* Paths a and b should be valid. */ + assert(rc_b == 0 && rc_b == 0); + /* + * The parser stopped because the end of one of the paths + * was reached. As JSON_TOKEN_END > JSON_TOKEN_{NUM, STR}, + * the path having more tokens has lower key.type value. + */ + return token_b.type - token_a.type; +} diff --git a/src/lib/json/json.h b/src/lib/json/json.h index 4ff2b9c67..aae337e29 100644 --- a/src/lib/json/json.h +++ b/src/lib/json/json.h @@ -30,6 +30,7 @@ * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ +#include #include "trivia/util.h" #ifdef __cplusplus @@ -222,6 +223,33 @@ json_lexer_create(struct json_lexer *lexer, const char *src, int src_len, int json_lexer_next_token(struct json_lexer *lexer, struct json_token *token); +/** + * Compare two JSON paths using Lexer class. + * - in case of paths that have same token-sequence prefix, + * the path having more tokens is assumed to be greater + * - both paths should be valid + * (may be tested with json_path_validate). + */ +int +json_path_cmp(const char *a, uint32_t a_len, const char *b, uint32_t b_len, + uint32_t index_base); + +/** + * Check if the passed JSON path is valid. + * Return 0 for valid path and error position for invalid. + */ +static inline int +json_path_validate(const char *path, uint32_t path_len, uint32_t index_base) +{ + struct json_lexer lexer; + json_lexer_create(&lexer, path, path_len, index_base); + struct json_token token; + int rc; + while ((rc = json_lexer_next_token(&lexer, &token)) == 0 && + token.type != JSON_TOKEN_END) {}; + return rc; +} + /** Create a JSON tree object to manage data relations. */ int json_tree_create(struct json_tree *tree); diff --git a/test/unit/json_path.c b/test/unit/json_path.c index 04d36688b..f345b8125 100644 --- a/test/unit/json_path.c +++ b/test/unit/json_path.c @@ -405,15 +405,50 @@ test_tree() footer(); } +void +test_path_cmp() +{ + const char *a = "Data[1][\"FIO\"].fname"; + uint32_t a_len = strlen(a); + const struct path_and_errpos rc[] = { + {a, 0}, + {"[\"Data\"][1].FIO[\"fname\"]", 0}, + {"Data[1]", 1}, + {"Data[1][\"FIO\"].fname[1]", -1}, + {"Data[1][\"Info\"].fname[1]", -1}, + }; + header(); + plan(lengthof(rc) + 2); + for (size_t i = 0; i < lengthof(rc); ++i) { + const char *path = rc[i].path; + int errpos = rc[i].errpos; + int rc = json_path_cmp(a, a_len, path, strlen(path), + TUPLE_INDEX_BASE); + if (rc > 0) rc = 1; + if (rc < 0) rc = -1; + is(rc, errpos, "path cmp result \"%s\" with \"%s\": " + "have %d, expected %d", a, path, rc, errpos); + } + const char *invalid = "Data[[1][\"FIO\"].fname"; + int ret = json_path_validate(a, strlen(a), TUPLE_INDEX_BASE); + is(ret, 0, "path %s is valid", a); + ret = json_path_validate(invalid, strlen(invalid), TUPLE_INDEX_BASE); + is(ret, 6, "path %s error pos %d expected %d", invalid, ret, 6); + + check_plan(); + footer(); +} + int main() { header(); - plan(3); + plan(4); test_basic(); test_errors(); test_tree(); + test_path_cmp(); int rc = check_plan(); footer(); diff --git a/test/unit/json_path.result b/test/unit/json_path.result index 0ee970c8c..cf0fa51c4 100644 --- a/test/unit/json_path.result +++ b/test/unit/json_path.result @@ -1,5 +1,5 @@ *** main *** -1..3 +1..4 *** test_basic *** 1..71 ok 1 - parse <[1]> @@ -158,4 +158,15 @@ ok 2 - subtests ok 54 - records iterated count 4 of 4 ok 3 - subtests *** test_tree: done *** + *** test_path_cmp *** + 1..7 + ok 1 - path cmp result "Data[1]["FIO"].fname" with "Data[1]["FIO"].fname": have 0, expected 0 + ok 2 - path cmp result "Data[1]["FIO"].fname" with "["Data"][1].FIO["fname"]": have 0, expected 0 + ok 3 - path cmp result "Data[1]["FIO"].fname" with "Data[1]": have 1, expected 1 + ok 4 - path cmp result "Data[1]["FIO"].fname" with "Data[1]["FIO"].fname[1]": have -1, expected -1 + ok 5 - path cmp result "Data[1]["FIO"].fname" with "Data[1]["Info"].fname[1]": have -1, expected -1 + ok 6 - path Data[1]["FIO"].fname is valid + ok 7 - path Data[[1]["FIO"].fname error pos 6 expected 6 +ok 4 - subtests + *** test_path_cmp: done *** *** main: done *** -- 2.19.2