func (db *TrailDB) NewEventFilter(query [][]FilterTerm) *EventFilter {
filter := EventFilter{filter: C.tdb_event_filter_new()}
for i, clause := range query {
if i > 0 {
err := C.tdb_event_filter_new_clause(filter.filter)
if err != 0 {
return nil
}
}
for _, term := range clause {
item := C.tdb_item(0)
field_id, err := db.GetField(term.Field)
if err == nil {
cs := C.CString(term.Value)
defer C.free(unsafe.Pointer(cs))
item = C.tdb_get_item(db.db,
C.tdb_field(field_id),
cs,
C.uint64_t(len(term.Value)))
}
isNegative := C.int(0)
if term.IsNegative {
isNegative = 1
}
ret := C.tdb_event_filter_add_term(filter.filter, item, isNegative)
if ret != 0 {
return nil
}
}
}
return &filter
}
func Open(s string) (*TrailDB, error) {
ok, er := exists(s)
if er != nil {
return nil, er
}
if !ok {
return nil, errors.New(s + ": Path doesn't exist")
}
db := C.tdb_init()
cs := C.CString(s)
defer C.free(unsafe.Pointer(cs))
err := C.tdb_open(db, cs)
if err != 0 {
return nil, errors.New(s + ": Failed to open traildb: " + errToString(err))
}
numFields := uint64(C.tdb_num_fields(db))
var fields []string
fieldNameToId := make(map[string]uint64)
// numFields contains timestamp too
for i := uint64(0); i <= uint64(numFields)-1; i++ {
fieldName := C.GoString(C.tdb_get_field_name(db, C.tdb_field(i)))
fieldNameToId[fieldName] = uint64(i)
fields = append(fields, fieldName)
}
return &TrailDB{
db: db,
NumTrails: uint64(C.tdb_num_trails(db)),
NumEvents: uint64(C.tdb_num_events(db)),
NumFields: numFields,
minTimestamp: uint64(C.tdb_min_timestamp(db)),
maxTimestamp: uint64(C.tdb_max_timestamp(db)),
fieldNames: fields,
fieldNameToId: fieldNameToId,
}, nil
}
func (db *TrailDB) GetField(field_name string) (uint64, error) {
field := C.tdb_field(0)
err := C.tdb_get_field(db.db, C.CString(field_name), &field)
if err != 0 {
return 0, errors.New(errToString(err))
}
return uint64(field), nil
}
func (db *TrailDB) FindTrails(filters map[string]string) ([]*Trail, error) {
var items []C.tdb_item
for k, v := range filters {
cs := C.CString(v)
defer C.free(unsafe.Pointer(cs))
item := C.tdb_get_item(db.db, C.tdb_field(db.fieldNameToId[k]), cs, C.uint64_t(len(v)))
items = append(items, item)
}
var result []*Trail
for i := uint64(0); i < db.NumTrails; i++ {
trail, err := NewTrail(db, i)
if err != nil {
return nil, err
}
for {
evt := trail.NextEvent()
if evt == nil {
trail.Close()
break
}
if evt.contains(items) {
returnTrail, err := NewTrail(db, i)
if err != nil {
return nil, err
}
result = append(result, returnTrail)
trail.Close()
break
}
}
}
return result, nil
}