func (this *Merge) processMatch(item value.AnnotatedValue,
context *Context, update, delete, insert Operator) bool {
kv, e := this.plan.Key().Evaluate(item, context)
if e != nil {
context.Error(errors.NewError(e, "Error evaluatating MERGE key."))
return false
}
ka := kv.Actual()
k, ok := ka.(string)
if !ok {
context.Error(errors.NewError(nil,
fmt.Sprintf("Invalid MERGE key %v of type %T.", ka, ka)))
return false
}
bvs, err := this.plan.Keyspace().Fetch([]string{k})
if err != nil {
context.Error(err)
return false
}
if len(bvs) > 0 {
bv := bvs[0].Value
// Matched; join source and target
if update != nil {
item.SetAttachment("target", bv)
}
abv := value.NewAnnotatedValue(bv)
item.SetField(this.plan.KeyspaceRef().Alias(), abv)
// Perform UPDATE and/or DELETE
if update != nil {
update.Input().ItemChannel() <- item
}
if delete != nil {
delete.Input().ItemChannel() <- item
}
} else {
// Not matched; INSERT
if insert != nil {
insert.Input().ItemChannel() <- item
}
}
return true
}
func (this *Unnest) processItem(item value.AnnotatedValue, context *Context) bool {
ev, err := this.plan.Term().Expression().Evaluate(item, context)
if err != nil {
context.Error(errors.NewError(err, "Error evaluating UNNEST path."))
return false
}
actuals := ev.Actual()
switch actuals.(type) {
case []interface{}:
case nil:
actuals = []interface{}(nil)
default:
actuals = []interface{}{actuals}
}
acts := actuals.([]interface{})
if len(acts) == 0 {
// Outer unnest
return !this.plan.Term().Outer() || this.sendItem(item)
}
// Attach and send
for i, act := range acts {
var av value.AnnotatedValue
if i < len(acts)-1 {
av = value.NewAnnotatedValue(item.Copy())
} else {
av = item
}
av.SetField(this.plan.Alias(), value.NewValue(act))
if !this.sendItem(av) {
return false
}
}
return true
}
func (this *Nest) processItem(item value.AnnotatedValue, context *Context) bool {
kv, e := this.plan.Term().Keys().Evaluate(item, context)
if e != nil {
context.Error(errors.NewError(e, "Error evaluating NEST keys."))
return false
}
actuals := kv.Actual()
switch actuals.(type) {
case []interface{}:
case nil:
actuals = []interface{}(nil)
default:
actuals = []interface{}{actuals}
}
acts := actuals.([]interface{})
if len(acts) == 0 {
// Outer nest
return !this.plan.Outer() || this.sendItem(item)
}
// Build list of keys
keys := make([]string, 0, len(acts))
for _, key := range acts {
k := value.NewValue(key).Actual()
switch k := k.(type) {
case string:
keys = append(keys, k)
}
}
// Fetch
pairs, err := this.plan.Keyspace().Fetch(keys)
if err != nil {
context.Error(err)
return false
}
found := len(pairs) > 0
if !found && !this.plan.Outer() {
return true
}
nvs := make([]interface{}, 0, len(pairs))
for i, pair := range pairs {
nestItem := pair.Value
var nv value.AnnotatedValue
// Apply projection, if any
projection := this.plan.Term().Projection()
if projection != nil {
projectedItem, e := projection.Evaluate(nestItem, context)
if e != nil {
context.Error(errors.NewError(e,
"Error evaluating nest path."))
return false
}
if projectedItem.Type() == value.MISSING {
continue
}
nv = value.NewAnnotatedValue(projectedItem)
} else {
nv = value.NewAnnotatedValue(nestItem)
}
nv.SetAttachment("meta", map[string]interface{}{"id": keys[i]})
nvs = append(nvs, nv)
}
// Attach and send
item.SetField(this.plan.Term().Alias(), nvs)
return this.sendItem(item)
}
func (this *Join) processItem(item value.AnnotatedValue, context *Context) bool {
kv, e := this.plan.Term().Keys().Evaluate(item, context)
if e != nil {
context.Error(errors.NewError(e, "Error evaluating JOIN keys."))
return false
}
actuals := kv.Actual()
switch actuals.(type) {
case []interface{}:
case nil:
actuals = []interface{}(nil)
default:
actuals = []interface{}{actuals}
}
acts := actuals.([]interface{})
if len(acts) == 0 {
// Outer join
return !this.plan.Outer() || this.sendItem(item)
}
// Build list of keys
keys := make([]string, 0, len(acts))
for _, key := range acts {
k := value.NewValue(key).Actual()
switch k := k.(type) {
case string:
keys = append(keys, k)
}
}
// Fetch
pairs, err := this.plan.Keyspace().Fetch(keys)
if err != nil {
context.Error(err)
return false
}
found := len(pairs) > 0
// Attach and send
for i, pair := range pairs {
joinItem := pair.Value
var jv value.AnnotatedValue
// Apply projection, if any
projection := this.plan.Term().Projection()
if projection != nil {
projectedItem, e := projection.Evaluate(joinItem, context)
if e != nil {
context.Error(errors.NewError(e,
"Error evaluating join path."))
return false
}
jv = value.NewAnnotatedValue(projectedItem)
} else {
jv = value.NewAnnotatedValue(joinItem)
}
jv.SetAttachment("meta", map[string]interface{}{"id": keys[i]})
var av value.AnnotatedValue
if i < len(pairs)-1 {
av = value.NewAnnotatedValue(item.Copy())
} else {
av = item
}
av.SetField(this.plan.Term().Alias(), jv)
if !this.sendItem(av) {
return false
}
}
return found || !this.plan.Outer() || this.sendItem(item)
}