Merge remote-tracking branch 'origin/issue93'

Conflicts:
	src/ejdb/tests/ejdbtest2.c

3 files changed, 129 insertions, 0 deletions

diff --git a/src/ejdb/ejdb.c b/src/ejdb/ejdb.c
index a1045e6..abdbaa6 100644
--- a/src/ejdb/ejdb.c
+++ b/src/ejdb/ejdb.c
@@ -592,6 +592,79 @@ EJQRESULT ejdbqryexecute(EJCOLL *coll, const EJQ *q, uint32_t *count, int qflags
     return res;
 }
 
+bson* ejdbqrydistinct(EJCOLL *coll, const char *fpath, bson *qobj, bson *orqobjs, int orqobjsnum, uint32_t *count, TCXSTR *log) {
+    assert(coll);
+    uint32_t icount = 0;
+    
+    bson *rqobj = qobj;
+    bson *hints = bson_create();
+    bson_init_as_query(hints);
+    bson_append_start_object(hints, "$fields");
+    bson_append_int(hints, fpath, 1);
+    bson_append_finish_object(hints);
+    bson_append_start_object(hints, "$orderby");
+    bson_append_int(hints, fpath, 1);
+    bson_append_finish_object(hints);
+    bson_finish(hints);
+
+    EJQ *q = NULL;
+    bson *rres = NULL;
+    *count = 0;
+
+    if (!rqobj) {
+        rqobj = bson_create();
+        bson_init(rqobj);
+        bson_finish(rqobj);
+    }
+    q = ejdbcreatequery(coll->jb, rqobj, orqobjs, orqobjsnum, hints);
+    if (q == NULL) {
+        goto fail;
+    }
+    if (q->flags & EJQUPDATING) {
+        _ejdbsetecode(coll->jb, JBEQERROR, __FILE__, __LINE__, __func__);
+        goto fail;
+    }
+    TCLIST *res = ejdbqryexecute(coll, q, &icount, 0, log);
+    rres = bson_create();
+    bson_init(rres);
+
+    bson_iterator bsi[2];
+    bson_iterator *prev = NULL, *cur;
+    int biind = 0;
+    char biindstr[TCNUMBUFSIZ];
+    memset(biindstr, '\0', 32);
+    int fplen = strlen(fpath);
+    for(int i = 0; i < TCLISTNUM(res); ++i) {
+        cur = bsi + (biind & 1);
+        BSON_ITERATOR_FROM_BUFFER(cur, TCLISTVALPTR(res, i));
+        bson_type bt = bson_find_fieldpath_value2(fpath, fplen, cur);
+        if (bt == BSON_EOO) {
+            continue;
+        }
+        
+        if (prev == NULL || bson_compare_it_current(prev, cur)) {
+            bson_numstrn(biindstr, TCNUMBUFSIZ, biind);
+            bson_append_field_from_iterator2(biindstr, cur, rres);
+            prev = cur;
+            biind++;
+        }
+    }
+    bson_finish(rres);
+    tclistdel(res);
+    
+    *count = biind;
+    
+fail:
+    if (q) {
+        ejdbquerydel(q);
+    }
+    if (rqobj != qobj) {
+        bson_destroy(rqobj);
+    }
+    bson_destroy(hints);
+    return rres;
+}
+
 int ejdbqresultnum(EJQRESULT qr) {
     return qr ? tclistnum(qr) : 0;
 }
diff --git a/src/ejdb/ejdb.h b/src/ejdb/ejdb.h
index d00c212..bb07773 100644
--- a/src/ejdb/ejdb.h
+++ b/src/ejdb/ejdb.h
@@ -496,6 +496,21 @@ EJDB_EXPORT void ejdbqresultdispose(EJQRESULT qr);
 EJDB_EXPORT uint32_t ejdbupdate(EJCOLL *jcoll, bson *qobj, bson *orqobjs, int orqobjsnum, bson *hints, TCXSTR *log);
 
 /**
+ * Provides 'distinct' operation over query (http://docs.mongodb.org/manual/reference/method/db.collection.distinct/).
+ * 
+ * @param jcoll EJDB database collection handle.
+ * @param fpath Field path to collect distinct values from.
+ * @param qobj Main BSON query object.
+ * @param orqobjs Array of additional OR query objects (joined with OR predicate).
+ * @param orqobjsnum Number of OR query objects.
+ * 
+ * NOTE: Queries with update instruction not supported.
+ * 
+ * @return Unique values by specified path and query (as BSON array)
+ */
+EJDB_EXPORT bson* ejdbqrydistinct(EJCOLL *jcoll, const char *fpath, bson *qobj, bson *orqobjs, int orqobjsnum, uint32_t *count, TCXSTR *log);
+
+/**
  * Synchronize content of a EJDB collection database with the file on device.
  * @param jcoll EJDB collection.
  * @return On success return true.
diff --git a/src/ejdb/tests/ejdbtest2.c b/src/ejdb/tests/ejdbtest2.c
index 5652c66..1e2f0dd 100644
--- a/src/ejdb/tests/ejdbtest2.c
+++ b/src/ejdb/tests/ejdbtest2.c
@@ -5521,6 +5521,46 @@ void testSlice(void) {
 }
 
 
+void testDistinct() {
+    EJCOLL *contacts = ejdbcreatecoll(jb, "contacts", NULL);
+    CU_ASSERT_PTR_NOT_NULL_FATAL(contacts);
+
+    int count;
+    TCXSTR *log;
+    bson *q1res; 
+
+    log = tcxstrnew();
+    q1res = ejdbqrydistinct(contacts, "address", NULL, NULL, 0, &count, log);
+
+    CU_ASSERT_PTR_NOT_NULL_FATAL(q1res);
+    CU_ASSERT_EQUAL(count, 4);
+    
+    bson_del(q1res);
+    
+    bson bsq1;
+    bson_init_as_query(&bsq1);
+    bson_append_string(&bsq1, "address.street", "Pirogova");
+    bson_finish(&bsq1);
+    CU_ASSERT_FALSE_FATAL(bsq1.err);
+
+    q1res = ejdbqrydistinct(contacts, "address.room", &bsq1, NULL, 0, &count, log);
+    
+    CU_ASSERT_PTR_NOT_NULL_FATAL(q1res);
+    CU_ASSERT_EQUAL(count, 1);
+    
+    bson_del(q1res);
+
+    q1res = ejdbqrydistinct(contacts, "nonexisted", NULL, NULL, 0, &count, log);
+    
+    CU_ASSERT_PTR_NOT_NULL_FATAL(q1res);
+    CU_ASSERT_EQUAL(count, 0);
+    
+    bson_del(q1res);
+
+    bson_destroy(&bsq1);
+    tcxstrdel(log);
+}
+
 
 int main() {
     setlocale(LC_ALL, "en_US.UTF-8");
@@ -5604,6 +5644,7 @@ int main() {
             (NULL == CU_add_test(pSuite, "testTicket99", testTicket99)) ||
             (NULL == CU_add_test(pSuite, "testTicket101", testTicket101)) || 
             (NULL == CU_add_test(pSuite, "testTicket110", testTicket110)) ||
+            (NULL == CU_add_test(pSuite, "testDistinct", testDistinct)) ||
 			(NULL == CU_add_test(pSuite, "testSlice", testSlice)) ||
             (NULL == CU_add_test(pSuite, "testMetaInfo", testMetaInfo))