static inline const char* getXactId( osrfMethodContext* ctx );
static inline void clearXactId( osrfMethodContext* ctx );
+static char* random_cursor_name();
static jsonObject* doFieldmapperSearch ( osrfMethodContext* ctx, osrfHash* class_meta,
jsonObject* where_hash, jsonObject* query_hash, int* err );
static jsonObject* oilsMakeFieldmapperFromResult( dbi_result, osrfHash* );
static char* searchJOIN ( const jsonObject*, const ClassInfo* left_info );
static char* searchWHERE ( const jsonObject* search_hash, const ClassInfo*, int, osrfMethodContext* );
static char* buildSELECT( const jsonObject*, jsonObject* rest_of_query,
- osrfHash* meta, osrfMethodContext* ctx );
+ osrfHash* meta, osrfMethodContext* ctx, char** cursor_name );
static char* buildOrderByFromArray( osrfMethodContext* ctx, const jsonObject* order_array );
char* buildQuery( osrfMethodContext* ctx, jsonObject* query, int flags );
static char* _sanitize_tz_name( const char* tz );
static char* _sanitize_savepoint_name( const char* sp );
+const char charset[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
+static char* random_cursor_name() {
+ char* str = safe_malloc(sizeof(char) * (ALIAS_STORE_SIZE + 1)); // 16 character cursor name + \0
+ int n;
+ for(n = 0; n < ALIAS_STORE_SIZE; n++) {
+ int key = rand() % (int) (sizeof charset - 1);
+ str[n] = charset[key];
+ }
+ str[ALIAS_STORE_SIZE] = '\0';
+ return str;
+}
+
/**
@brief Connect to the database.
@return A database connection if successful, or NULL if not.
*/
dbi_conn oilsConnectDB( const char* mod_name ) {
+ srand(time(NULL)); // In case we need some randomness, just once per db connection.
+
osrfLogDebug( OSRF_LOG_MARK, "Attempting to initialize libdbi..." );
if( dbi_initialize( NULL ) == -1 ) {
osrfLogError( OSRF_LOG_MARK, "Unable to initialize libdbi" );
};
}
if( writehandle ) {
+ if( !dbi_conn_query( writehandle, "CLOSE ALL;" ) ) {
+ const char* msg;
+ int errnum = dbi_conn_error( writehandle, &msg );
+ osrfLogWarning( OSRF_LOG_MARK, "Unable to release cursors: %d %s",
+ errnum, msg ? msg : "(No description available)" );
+ }
if( !dbi_conn_query( writehandle, "SELECT auditor.clear_audit_info();" ) ) {
const char* msg;
int errnum = dbi_conn_error( writehandle, &msg );
The SELECT statements built here are distinct from those built for the json_query method.
*/
static char* buildSELECT ( const jsonObject* search_hash, jsonObject* rest_of_query,
- osrfHash* meta, osrfMethodContext* ctx ) {
+ osrfHash* meta, osrfMethodContext* ctx, char** cursor_name ) {
const char* locale = osrf_message_get_last_locale();
if( !table )
table = strdup( "(null)" );
- buffer_fadd( sql_buf, "SELECT %s FROM %s AS \"%s\"", col_list, table, core_class );
+ *cursor_name = random_cursor_name();
+
+ buffer_fadd( sql_buf, "DECLARE \"%s\" NO SCROLL CURSOR WITH HOLD FOR SELECT %s FROM %s AS \"%s\"", *cursor_name, col_list, table, core_class );
free( col_list );
free( table );
free( pred );
}
- // Add the ORDER BY, LIMIT, and/or OFFSET clauses, if present
+ // Add the ORDER BY, if present
if( rest_of_query ) {
const jsonObject* order_by = NULL;
if( ( order_by = jsonObjectGetKeyConst( rest_of_query, "order_by" )) ){
free( order_by_list );
}
-
- const jsonObject* limit = jsonObjectGetKeyConst( rest_of_query, "limit" );
- if( limit ) {
- const char* str = jsonObjectGetString( limit );
- if (str) {
- buffer_fadd(
- sql_buf,
- " LIMIT %d",
- atoi(str)
- );
- }
- }
-
- const jsonObject* offset = jsonObjectGetKeyConst( rest_of_query, "offset" );
- if( offset ) {
- const char* str = jsonObjectGetString( offset );
- if (str) {
- buffer_fadd(
- sql_buf,
- " OFFSET %d",
- atoi( str )
- );
- }
- }
}
if( defaultselhash )
int i_respond_directly = 0;
int flesh_depth = 0;
+ int offset = 0;
+ int limit = 0;
+ int cursor_page_size = 5;
+ char* cursor_name;
- char* sql = buildSELECT( where_hash, query_hash, class_meta, ctx );
+ char* sql = buildSELECT( where_hash, query_hash, class_meta, ctx, &cursor_name );
if( !sql ) {
osrfLogDebug( OSRF_LOG_MARK, "Problem building query, returning NULL" );
*err = -1;
}
+ const jsonObject* limit_o = jsonObjectGetKeyConst( query_hash, "limit" );
+ if( limit_o ) {
+ limit = (int) jsonObjectGetNumber( limit_o );
+ } else {
+ limit = -1;
+ }
+
+ const jsonObject* offset_o = jsonObjectGetKeyConst( query_hash, "offset" );
+ if( offset_o ) {
+ offset = (int) jsonObjectGetNumber( offset_o );
+ } else {
+ offset = -1;
+ }
+
+ // set cursor_page_size to the largest of the three
+ if (cursor_page_size < offset) cursor_page_size = offset;
+ if (cursor_page_size < limit) cursor_page_size = limit;
+
+ // Declares a cursor
dbi_result result = dbi_conn_query( dbhandle, sql );
if( NULL == result ) {
i_respond_directly = ( *methodtype == 'r' || *methodtype == 'i' || *methodtype == 's' );
rs_size = (int *) safe_malloc( sizeof(int) ); // will be freed by sessionDataFree()
- unsigned long long result_count = dbi_result_get_numrows( result );
+ unsigned long long result_count = cursor_page_size;
*rs_size = (int) result_count * (flesh_depth + 1); // yes, we could lose some bits, but come on
osrfHashSet( (osrfHash *) ctx->session->userData, rs_size, "rs_size_req_%d", ctx->request );
}
+
+ dbi_result_free( result ); // toss the declare result
+ result = dbi_conn_queryf( dbhandle, "FETCH %d FROM \"%s\";", cursor_page_size, cursor_name );
+
+ if( NULL == result ) {
+ const char* msg;
+ int errnum = dbi_conn_error( dbhandle, &msg );
+ osrfLogError(OSRF_LOG_MARK, "%s: Error retrieving %s with query [%s]: %d %s",
+ modulename, osrfHashGet( class_meta, "fieldmapper" ), sql, errnum,
+ msg ? msg : "(No description available)" );
+ if( !oilsIsDBConnected( dbhandle ))
+ osrfAppSessionPanic( ctx->session );
+ osrfAppSessionStatus(
+ ctx->session,
+ OSRF_STATUS_INTERNALSERVERERROR,
+ "osrfMethodException",
+ ctx->request,
+ "Severe query error -- see error log for more details"
+ );
+ *err = -1;
+ free( sql );
+ return NULL;
+
+ }
+
if( dbi_result_first_row( result )) {
// Convert each row to a JSON_ARRAY of column values, and enclose those objects
// eliminate the duplicates.
osrfLogDebug( OSRF_LOG_MARK, "Query returned at least one row" );
osrfHash* dedup = osrfNewHash();
+ int cursor_page_remaining = cursor_page_size;
do {
+ cursor_page_remaining--;
row_obj = oilsMakeFieldmapperFromResult( result, class_meta );
char* pkey_val = oilsFMGetString( row_obj, pkey );
if( osrfHashGet( dedup, pkey_val ) ) {
} else {
if( !enforce_pcrud || !need_to_verify ||
verifyObjectPCRUD( ctx, class_meta, row_obj, 0 /* means check user data for rs_size */ )) {
- osrfHashSet( dedup, pkey_val, pkey_val );
- jsonObjectPush( res_list, row_obj );
+ if (offset > -1 && offset) {
+ offset--;
+ } else {
+ if (limit > -1 && limit) limit--;
+ osrfHashSet( dedup, pkey_val, pkey_val );
+ jsonObjectPush( res_list, row_obj );
+ }
}
}
- } while( dbi_result_next_row( result ));
+ if (!cursor_page_remaining) { // fetch next page
+ cursor_page_remaining = cursor_page_size;
+ dbi_result_free( result );
+ result = dbi_conn_queryf( dbhandle, "FETCH %d FROM \"%s\";", cursor_page_size, cursor_name );
+
+ if( NULL == result ) {
+ const char* msg;
+ int errnum = dbi_conn_error( dbhandle, &msg );
+ osrfLogError(OSRF_LOG_MARK, "%s: Error retrieving %s with query [%s]: %d %s",
+ modulename, osrfHashGet( class_meta, "fieldmapper" ), sql, errnum,
+ msg ? msg : "(No description available)" );
+ if( !oilsIsDBConnected( dbhandle ))
+ osrfAppSessionPanic( ctx->session );
+ osrfAppSessionStatus(
+ ctx->session,
+ OSRF_STATUS_INTERNALSERVERERROR,
+ "osrfMethodException",
+ ctx->request,
+ "Severe query error -- see error log for more details"
+ );
+ *err = -1;
+ free( sql );
+ return NULL;
+ }
+ }
+ } while(
+ limit && ( // limit is -1 (none) or not yet decremented to 0
+ (cursor_page_remaining == cursor_page_size && dbi_result_first_row(result)) || // on a new page, and there's a row
+ (cursor_page_remaining != cursor_page_size && dbi_result_next_row(result)) // on the same page, and there's a row
+ )
+ );
osrfHashFree( dedup );
} else {
/* clean up the query */
dbi_result_free( result );
+ result = dbi_conn_queryf( dbhandle, "CLOSE \"%s\";", cursor_name );
+ dbi_result_free( result );
free( sql );
// If we're asked to flesh, and there's anything to flesh, then flesh it
projects / working / Evergreen.git / commitdiff