Add 'user friendly' datastore API.

service/rawdatastore/context.go

Index: service/rawdatastore/context.go
diff --git a/service/rawdatastore/context.go b/service/rawdatastore/context.go
deleted file mode 100644
index f1603b5af8a983ffa67400114b9a09157c3d62c8..0000000000000000000000000000000000000000
--- a/service/rawdatastore/context.go
+++ /dev/null
@@ -1,79 +0,0 @@
-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package rawdatastore
-
-import (
-	"golang.org/x/net/context"
-)
-
-type key int
-
-var (
-	rawDatastoreKey       key
-	rawDatastoreFilterKey key = 1
-)
-
-// Factory is the function signature for factory methods compatible with
-// SetFactory.
-type Factory func(context.Context) Interface
-
-// Filter is the function signature for a filter RDS implementation. It
-// gets the current RDS implementation, and returns a new RDS implementation
-// backed by the one passed in.
-type Filter func(context.Context, Interface) Interface
-
-// getUnfiltered gets gets the Interface implementation from context without
-// any of the filters applied.
-func getUnfiltered(c context.Context) Interface {
-	if f, ok := c.Value(rawDatastoreKey).(Factory); ok && f != nil {
-		return f(c)
-	}
-	return nil
-}
-
-// Get gets the Interface implementation from context.
-func Get(c context.Context) Interface {
-	ret := getUnfiltered(c)
-	if ret == nil {
-		return nil
-	}
-	for _, f := range getCurFilters(c) {
-		ret = f(c, ret)
-	}
-	return applyCheckFilter(c, ret)
-}
-
-// SetFactory sets the function to produce Datastore instances, as returned by
-// the Get method.
-func SetFactory(c context.Context, rdsf Factory) context.Context {
-	return context.WithValue(c, rawDatastoreKey, rdsf)
-}
-
-// Set sets the current Datastore object in the context. Useful for testing with
-// a quick mock. This is just a shorthand SetFactory invocation to set a factory
-// which always returns the same object.
-func Set(c context.Context, rds Interface) context.Context {
-	return SetFactory(c, func(context.Context) Interface { return rds })
-}
-
-func getCurFilters(c context.Context) []Filter {
-	curFiltsI := c.Value(rawDatastoreFilterKey)
-	if curFiltsI != nil {
-		return curFiltsI.([]Filter)
-	}
-	return nil
-}
-
-// AddFilters adds Interface filters to the context.
-func AddFilters(c context.Context, filts ...Filter) context.Context {
-	if len(filts) == 0 {
-		return c
-	}
-	cur := getCurFilters(c)
-	newFilts := make([]Filter, 0, len(cur)+len(filts))
-	newFilts = append(newFilts, getCurFilters(c)...)
-	newFilts = append(newFilts, filts...)
-	return context.WithValue(c, rawDatastoreFilterKey, newFilts)
-}