// Apply applies a Mutation to a specific row.
func (t *Table) Apply(ctx context.Context, row string, m *Mutation, opts ...ApplyOption) error {
ctx = mergeMetadata(ctx, t.md)
after := func(res proto.Message) {
for _, o := range opts {
o.after(res)
}
}
var callOptions []gax.CallOption
if m.cond == nil {
req := &btpb.MutateRowRequest{
TableName: t.c.fullTableName(t.table),
RowKey: []byte(row),
Mutations: m.ops,
}
if mutationsAreRetryable(m.ops) {
callOptions = retryOptions
}
var res *btpb.MutateRowResponse
err := gax.Invoke(ctx, func(ctx context.Context) error {
var err error
res, err = t.c.client.MutateRow(ctx, req)
return err
}, callOptions...)
if err == nil {
after(res)
}
return err
}
req := &btpb.CheckAndMutateRowRequest{
TableName: t.c.fullTableName(t.table),
RowKey: []byte(row),
PredicateFilter: m.cond.proto(),
}
if m.mtrue != nil {
req.TrueMutations = m.mtrue.ops
}
if m.mfalse != nil {
req.FalseMutations = m.mfalse.ops
}
if mutationsAreRetryable(req.TrueMutations) && mutationsAreRetryable(req.FalseMutations) {
callOptions = retryOptions
}
var cmRes *btpb.CheckAndMutateRowResponse
err := gax.Invoke(ctx, func(ctx context.Context) error {
var err error
cmRes, err = t.c.client.CheckAndMutateRow(ctx, req)
return err
}, callOptions...)
if err == nil {
after(cmRes)
}
return err
}
// ApplyBulk applies multiple Mutations.
// Each mutation is individually applied atomically,
// but the set of mutations may be applied in any order.
//
// Two types of failures may occur. If the entire process
// fails, (nil, err) will be returned. If specific mutations
// fail to apply, ([]err, nil) will be returned, and the errors
// will correspond to the relevant rowKeys/muts arguments.
//
// Conditional mutations cannot be applied in bulk and providing one will result in an error.
func (t *Table) ApplyBulk(ctx context.Context, rowKeys []string, muts []*Mutation, opts ...ApplyOption) ([]error, error) {
ctx = mergeMetadata(ctx, t.md)
if len(rowKeys) != len(muts) {
return nil, fmt.Errorf("mismatched rowKeys and mutation array lengths: %d, %d", len(rowKeys), len(muts))
}
origEntries := make([]*entryErr, len(rowKeys))
for i, key := range rowKeys {
mut := muts[i]
if mut.cond != nil {
return nil, errors.New("conditional mutations cannot be applied in bulk")
}
origEntries[i] = &entryErr{Entry: &btpb.MutateRowsRequest_Entry{RowKey: []byte(key), Mutations: mut.ops}}
}
// entries will be reduced after each invocation to just what needs to be retried.
entries := make([]*entryErr, len(rowKeys))
copy(entries, origEntries)
err := gax.Invoke(ctx, func(ctx context.Context) error {
err := t.doApplyBulk(ctx, entries, opts...)
if err != nil {
// We want to retry the entire request with the current entries
return err
}
entries = t.getApplyBulkRetries(entries)
if len(entries) > 0 && len(idempotentRetryCodes) > 0 {
// We have at least one mutation that needs to be retried.
// Return an arbitrary error that is retryable according to callOptions.
return grpc.Errorf(idempotentRetryCodes[0], "Synthetic error: partial failure of ApplyBulk")
}
return nil
}, retryOptions...)
if err != nil {
return nil, err
}
// Accumulate all of the errors into an array to return, interspersed with nils for successful
// entries. The absence of any errors means we should return nil.
var errs []error
var foundErr bool
for _, entry := range origEntries {
if entry.Err != nil {
foundErr = true
}
errs = append(errs, entry.Err)
}
if foundErr {
return errs, nil
}
return nil, nil
}
// ReadRows reads rows from a table. f is called for each row.
// If f returns false, the stream is shut down and ReadRows returns.
// f owns its argument, and f is called serially in order by row key.
//
// By default, the yielded rows will contain all values in all cells.
// Use RowFilter to limit the cells returned.
func (t *Table) ReadRows(ctx context.Context, arg RowSet, f func(Row) bool, opts ...ReadOption) error {
ctx = mergeMetadata(ctx, t.md)
var prevRowKey string
err := gax.Invoke(ctx, func(ctx context.Context) error {
req := &btpb.ReadRowsRequest{
TableName: t.c.fullTableName(t.table),
Rows: arg.proto(),
}
for _, opt := range opts {
opt.set(req)
}
ctx, cancel := context.WithCancel(ctx) // for aborting the stream
defer cancel()
stream, err := t.c.client.ReadRows(ctx, req)
if err != nil {
return err
}
cr := newChunkReader()
for {
res, err := stream.Recv()
if err == io.EOF {
break
}
if err != nil {
// Reset arg for next Invoke call.
arg = arg.retainRowsAfter(prevRowKey)
return err
}
for _, cc := range res.Chunks {
row, err := cr.Process(cc)
if err != nil {
// No need to prepare for a retry, this is an unretryable error.
return err
}
if row == nil {
continue
}
prevRowKey = row.Key()
if !f(row) {
// Cancel and drain stream.
cancel()
for {
if _, err := stream.Recv(); err != nil {
// The stream has ended. We don't return an error
// because the caller has intentionally interrupted the scan.
return nil
}
}
}
}
if err := cr.Close(); err != nil {
// No need to prepare for a retry, this is an unretryable error.
return err
}
}
return err
}, retryOptions...)
return err
}