commit 1320a0e50fc8e1db9a8f06184a276450a7f4e1a8
author Mike Burrows <m3b@google.com> Thu Mar 31 14:05:21 2016 -0700
committer Mike Burrows <m3b@google.com> Thu Mar 31 14:05:21 2016 -0700
tree 7a9e49982551c5811dcfb8e6239ef462b01f7695
parent babf01ede681304b0aa65ea6f2bdf355cb5483a3

v.io/v23/services/syncbase:  use interface{} for values from syncbase's Exec() and Watch()

Use interface{} for values from syncbase's Exec() and Watch(), to
match the interfaces of Put(), Get(), and Scan().

Reviewers might like to look at syncbase/model.go first to
see the changes to the public API.

In v.io/v23:

services/syncbase/types.vdl
        StoreChange.Value is now an "any" (a *vom.RawBytes in
        Go), rather than a []byte.

services/syncbase/service.vdl
        There is a new error to indicate that a stream header is
        badly formatted.  Previously, the error in this case was
        whatever error vom.Decode() returned; see database.go

syncbase/featuretests/client_v23_test.go
        Now uses the Value() method on WatchChange, rather than
        accessing its (now private) field directly.

syncbase/featuretests/restartability_v23_test.go
        Now uses the Value() method on WatchChange, rather than
        accessing its (now private) field directly.

syncbase/batch_test.go
        Uses a Go type assertion in an interface{} rather than
        ToValue() on a RawBytes.

syncbase/client_test.go
        Use a testutil.WatchChangeTest struct instead of a
        syncbase.WatchChange struct to hold the "wanted" values,
        because syncbase.WatchChange's value field is now private.

        Use testutil.WatchChangeEq() instead of
        reflect.DeepEqual(), for the same reason.

syncbase/database.go
        Uses a Go type assertion in an interface{} rather than
        ToValue() on a RawBytes. This is where a new error is
        returned rather than returning the error from ToValue();
        see service.vdl.

syncbase/exec_test.go
        Use interface{} instead of *vom.RawBytes in results from
        Exec().

syncbase/model.go
        ResultStream (from Exec()) now has
		ResultCount() int
		Result(int, interface{}) error
	calls instead of a single
		Result() []*vom.RawBytes
	call.

        WatchChange (from Watch()) no longer has a public field
        "ValueBytes []byte" but now has a private value
        "*vom.RawBytes" field.  Clients are required to use the
        pre-existing Value() method that fills in an interface{}.

syncbase/result_stream.go
        Add a "decoded []interface{}" field to resultStream to
        cache the decoded results from the Advance() call to the
        Result() call.  The reason for performing the decoding in
        Advance() is because Advance() is permitted to signal an
        error (such as a decoding error), while Result() may not.

        Advance() is changed to decode the values in "curr" into
        "decoded", and to return an error on decoding failures.

        Result() is changed to return a vector of interface{},
        rather than a vector of *vom.RawBytes.

syncbase/syncgroup_v23_test.go
        Now uses the Value() method on WatchChange, rather than
        accessing its (now private) field directly.

syncbase/watch_stream.go
        The old, public "ValueBytes" field of WatchChange is now
        private, andf called "value".

In v.io/x/ref:

cmd/sb/internal/writer/writer.go
        getJustification() now uses a Go type switch rather than
        a switch on VDL types, because it's working with
        interface{} values rather than *vom.RawBytes values.

        toRawString() and topJson now each take an interface{}
        rather than a *vom.RawBytes.

cmd/sb/internal/writer/writer_test.go
        Use interface{} instead of *vom.RawBytes in several
        places.

services/syncbase/server/database_watch.go
        In each of scanInitialState() and processLogBatch(),
        convert the []byte value from leveldb to *voim.RawBytes
        to add to the syncbase.StoreChange; see types.vdl.

ervices/syncbase/server/testutil/util.go
        In CheckExec(), use interface{} instead of *vom.RawBytes.

        Add struct WatchChangeTest to allow tests to construct
        "wanted" values that have a ValueBytes field; the
        corresponding field in WatchChange is now private; see
        model.go.

        Add func WatchChangeEq() that allows tests to compare a
        WatchChange against a WatchChangeTest, since they can no
        longer use reflect.DeepEqual().

MultiPart: 1/3
Change-Id: I908596231c1ddd44797bf49823c1839042701116