Golang errors.NewEvaluationError函数代码示例

func (this *ValueScan) RunOnce(context *Context, parent value.Value) {
	this.once.Do(func() {
		defer context.Recover()       // Recover from any panic
		defer close(this.itemChannel) // Broadcast that I have stopped
		defer this.notify()           // Notify that I have stopped

		pairs := this.plan.Values()
		for _, pair := range pairs {
			key, err := pair.Key.Evaluate(parent, context)
			if err != nil {
				context.Error(errors.NewEvaluationError(err, "VALUES"))
				return
			}

			val, err := pair.Value.Evaluate(parent, context)
			if err != nil {
				context.Error(errors.NewEvaluationError(err, "VALUES"))
				return
			}

			av := value.NewAnnotatedValue(nil)
			av.SetAttachment("key", key)
			av.SetAttachment("value", val)

			if !this.sendItem(av) {
				return
			}
		}
	})
}

func (this *Order) Less(i, j int) bool {
	v1 := this.values[i]
	v2 := this.values[j]

	var ev1, ev2 value.Value
	var c int
	var e error

	for i, term := range this.plan.Terms() {
		s := this.terms[i]

		sv1 := v1.GetAttachment(s)
		switch sv1 := sv1.(type) {
		case value.Value:
			ev1 = sv1
		default:
			ev1, e = term.Expression().Evaluate(v1, this.context)
			if e != nil {
				this.context.Error(errors.NewEvaluationError(e, "ORDER BY"))
				return false
			}

			v1.SetAttachment(s, ev1)
		}

		sv2 := v2.GetAttachment(s)
		switch sv2 := sv2.(type) {
		case value.Value:
			ev2 = sv2
		default:
			ev2, e = term.Expression().Evaluate(v2, this.context)
			if e != nil {
				this.context.Error(errors.NewEvaluationError(e, "ORDER BY"))
				return false
			}

			v2.SetAttachment(s, ev2)
		}

		c = ev1.Collate(ev2)

		if c == 0 {
			continue
		} else if term.Descending() {
			return c > 0
		} else {
			return c < 0
		}
	}

	return false
}

func (this *KeyScan) RunOnce(context *Context, parent value.Value) {
	this.once.Do(func() {
		defer context.Recover()       // Recover from any panic
		defer close(this.itemChannel) // Broadcast that I have stopped
		defer this.notify()           // Notify that I have stopped

		keys, e := this.plan.Keys().Evaluate(parent, context)
		if e != nil {
			context.Error(errors.NewEvaluationError(e, "KEYS"))
			return
		}

		actuals := keys.Actual()
		switch actuals.(type) {
		case []interface{}:
		case nil:
			actuals = []interface{}(nil)
		default:
			actuals = []interface{}{actuals}
		}

		acts := actuals.([]interface{})

		for _, key := range acts {
			cv := value.NewScopeValue(make(map[string]interface{}), parent)
			av := value.NewAnnotatedValue(cv)
			av.SetAttachment("meta", map[string]interface{}{"id": key})
			if !this.sendItem(av) {
				return
			}
		}
	})
}

func (this *InitialProject) processTerms(item value.AnnotatedValue, context *Context) bool {
	n := len(this.plan.Terms())
	sv := value.NewScopeValue(make(map[string]interface{}, n), item)
	pv := value.NewAnnotatedValue(sv)
	pv.SetAnnotations(item)

	p := value.NewValue(make(map[string]interface{}, n+32))
	pv.SetAttachment("projection", p)

	for _, term := range this.plan.Terms() {
		if term.Result().Alias() != "" {
			v, err := term.Result().Expression().Evaluate(item, context)
			if err != nil {
				context.Error(errors.NewEvaluationError(err, "projection"))
				return false
			}

			p.SetField(term.Result().Alias(), v)

			// Explicit aliases override data
			if term.Result().As() != "" {
				pv.SetField(term.Result().As(), v)
			}
		} else {
			// Star
			starval := item.GetValue()
			if term.Result().Expression() != nil {
				var err error
				starval, err = term.Result().Expression().Evaluate(item, context)
				if err != nil {
					context.Error(errors.NewEvaluationError(err, "projection"))
					return false
				}
			}

			// Latest star overwrites previous star
			switch sa := starval.Actual().(type) {
			case map[string]interface{}:
				for k, v := range sa {
					p.SetField(k, v)
				}
			}
		}
	}

	return this.sendItem(pv)
}

func (this *IndexNest) fetch(entries []*datastore.IndexEntry, context *Context) (
	[]interface{}, bool) {
	// Build list of keys
	var keys []string
	if len(entries) <= 16 {
		keys = _NEST_INDEX_STRING_POOL.Get()
		defer _NEST_INDEX_STRING_POOL.Put(keys)
	} else {
		keys = make([]string, 0, len(entries))
	}

	for _, e := range entries {
		keys = append(keys, e.PrimaryKey)
	}

	// Fetch
	pairs, errs := this.plan.Keyspace().Fetch(keys)

	fetchOk := true
	for _, err := range errs {
		context.Error(err)
		if err.IsFatal() {
			fetchOk = false
		}
	}

	if len(pairs) == 0 {
		return nil, fetchOk
	}

	projection := this.plan.Term().Projection()
	nvs := make([]interface{}, 0, len(pairs))
	for _, pair := range pairs {
		nestItem := pair.Value
		var nv value.AnnotatedValue

		// Apply projection, if any
		if projection != nil {
			projectedItem, e := projection.Evaluate(nestItem, context)
			if e != nil {
				context.Error(errors.NewEvaluationError(e, "nest path"))
				return nil, false
			}

			if projectedItem.Type() == value.MISSING {
				continue
			}

			nv = value.NewAnnotatedValue(projectedItem)
			nv.SetAnnotations(nestItem)
		} else {
			nv = nestItem
		}

		nvs = append(nvs, nv)
	}

	return nvs, fetchOk
}

func (this *Cover) Evaluate(item value.Value, context Context) (value.Value, error) {
	var rv value.Value
	switch item := item.(type) {
	case value.AnnotatedValue:
		rv = item.GetCover(this.text)
	}

	if rv == nil {
		return value.MISSING_VALUE, errors.NewEvaluationError(nil, "cover("+this.text+")")
	}

	return rv, nil
}

func (this *Filter) processItem(item value.AnnotatedValue, context *Context) bool {
	val, e := this.plan.Condition().Evaluate(item, context)
	if e != nil {
		context.Error(errors.NewEvaluationError(e, "filter"))
		return false
	}

	if val.Truth() {
		return this.sendItem(item)
	} else {
		return true
	}
}

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.NewEvaluationError(e, "MERGE key"))
		return false
	}

	ka := kv.Actual()
	k, ok := ka.(string)
	if !ok {
		context.Error(errors.NewInvalidValueError(
			fmt.Sprintf("Invalid MERGE key %v of type %T.", ka, ka)))
		return false
	}

	timer := time.Now()

	fetchOk := true
	bvs, errs := this.plan.Keyspace().Fetch([]string{k})

	this.duration += time.Since(timer)

	for _, err := range errs {
		context.Error(err)
		if err.IsFatal() {
			fetchOk = false
		}
	}

	if len(bvs) > 0 {
		bv := bvs[0]
		item.SetField(this.plan.KeyspaceRef().Alias(), bv.Value)

		// 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 fetchOk
}

func (this *IntermediateGroup) processItem(item value.AnnotatedValue, context *Context) bool {
	// Generate the group key
	var gk string
	if len(this.plan.Keys()) > 0 {
		var e error
		gk, e = groupKey(item, this.plan.Keys(), context)
		if e != nil {
			context.Fatal(errors.NewEvaluationError(e, "GROUP key"))
			return false
		}
	}

	// Get or seed the group value
	gv := this.groups[gk]
	if gv == nil {
		gv = item
		this.groups[gk] = gv
		return true
	}

	// Cumulate aggregates
	part, ok := item.GetAttachment("aggregates").(map[string]value.Value)
	if !ok {
		context.Fatal(errors.NewInvalidValueError(
			fmt.Sprintf("Invalid partial aggregates %v of type %T", part, part)))
		return false
	}

	cumulative := gv.GetAttachment("aggregates").(map[string]value.Value)
	if !ok {
		context.Fatal(errors.NewInvalidValueError(
			fmt.Sprintf("Invalid cumulative aggregates %v of type %T", cumulative, cumulative)))
		return false
	}

	for _, agg := range this.plan.Aggregates() {
		a := agg.String()
		v, e := agg.CumulateIntermediate(part[a], cumulative[a], context)
		if e != nil {
			context.Fatal(errors.NewGroupUpdateError(
				e, "Error updating intermediate GROUP value."))
			return false
		}

		cumulative[a] = v
	}

	return true
}

func (this *IndexJoin) processItem(item value.AnnotatedValue, context *Context) bool {
	idv, e := this.plan.IdExpr().Evaluate(item, context)
	if e != nil {
		context.Error(errors.NewEvaluationError(e, fmt.Sprintf("JOIN FOR %s", this.plan.For())))
		return false
	}

	found, foundOne := false, false

	if idv.Type() == value.STRING {
		var wg sync.WaitGroup
		defer wg.Wait()

		id := idv.Actual().(string)
		conn := datastore.NewIndexConnection(context)
		defer notifyConn(conn.StopChannel()) // Notify index that I have stopped

		wg.Add(1)
		go this.scan(id, context, conn, &wg)

		var entry *datastore.IndexEntry
		ok := true
		for ok {
			select {
			case <-this.stopChannel:
				return false
			default:
			}

			select {
			case entry, ok = <-conn.EntryChannel():
				t := time.Now()

				if ok {
					foundOne, ok = this.joinEntry(item, entry, context)
					found = found || foundOne
				}

				this.duration += time.Since(t)
			case <-this.stopChannel:
				return false
			}
		}
	}

	return found || !this.plan.Outer() || this.sendItem(item)
}

func (this *InitialProject) processItem(item value.AnnotatedValue, context *Context) bool {
	terms := this.plan.Terms()
	n := len(terms)

	if n > 1 {
		return this.processTerms(item, context)
	}

	if n == 0 {
		return this.sendItem(item)
	}

	// n == 1

	result := terms[0].Result()
	expr := result.Expression()

	if result.Star() && (expr == expression.SELF || expr == nil) {
		// Unprefixed star
		if item.Type() == value.OBJECT {
			return this.sendItem(item)
		} else {
			return this.sendItem(_EMPTY_ANNOTATED_VALUE)
		}
	} else if this.plan.Projection().Raw() {
		// Raw projection of an expression
		v, err := expr.Evaluate(item, context)
		if err != nil {
			context.Error(errors.NewEvaluationError(err, "projection"))
			return false
		}

		if result.As() == "" {
			return this.sendItem(value.NewAnnotatedValue(v))
		}

		sv := value.NewScopeValue(make(map[string]interface{}, 1), item)
		sv.SetField(result.As(), v)
		av := value.NewAnnotatedValue(sv)
		av.SetAttachment("projection", v)
		return this.sendItem(av)
	} else {
		// Any other projection
		return this.processTerms(item, context)
	}
}

func eval(cx expression.Expressions, context *Context, parent value.Value) (value.Values, bool) {
	if cx == nil {
		return nil, true
	}

	cv := make(value.Values, len(cx))
	var e error
	for i, expr := range cx {
		cv[i], e = expr.Evaluate(parent, context)
		if e != nil {
			context.Error(errors.NewEvaluationError(e, "filter term"))
			return nil, false
		}
	}

	return cv, true
}

func (this *InitialGroup) processItem(item value.AnnotatedValue, context *Context) bool {
	// Generate the group key
	var gk string
	if len(this.plan.Keys()) > 0 {
		var e error
		gk, e = groupKey(item, this.plan.Keys(), context)
		if e != nil {
			context.Fatal(errors.NewEvaluationError(e, "GROUP key"))
			return false
		}
	}

	// Get or seed the group value
	gv := this.groups[gk]
	if gv == nil {
		gv = item
		this.groups[gk] = gv

		aggregates := make(map[string]value.Value, len(this.plan.Aggregates()))
		gv.SetAttachment("aggregates", aggregates)
		for _, agg := range this.plan.Aggregates() {
			aggregates[agg.String()] = agg.Default()
		}
	}

	// Cumulate aggregates
	aggregates, ok := gv.GetAttachment("aggregates").(map[string]value.Value)
	if !ok {
		context.Fatal(errors.NewInvalidValueError(
			fmt.Sprintf("Invalid aggregates %v of type %T", aggregates, aggregates)))
		return false
	}

	for _, agg := range this.plan.Aggregates() {
		v, e := agg.CumulateInitial(item, aggregates[agg.String()], context)
		if e != nil {
			context.Fatal(errors.NewGroupUpdateError(e, "Error updating initial GROUP value."))
			return false
		}

		aggregates[agg.String()] = v
	}

	return true
}

func (this *Let) processItem(item value.AnnotatedValue, context *Context) bool {
	n := len(this.plan.Bindings())
	cv := value.NewScopeValue(make(map[string]interface{}, n), item)
	lv := value.NewAnnotatedValue(cv)
	lv.SetAnnotations(item)

	for _, b := range this.plan.Bindings() {
		v, e := b.Expression().Evaluate(item, context)
		if e != nil {
			context.Error(errors.NewEvaluationError(e, "LET"))
			return false
		}

		lv.SetField(b.Variable(), v)
	}

	return this.sendItem(lv)
}

func (this *FinalGroup) processItem(item value.AnnotatedValue, context *Context) bool {
	// Generate the group key
	var gk string
	if len(this.plan.Keys()) > 0 {
		var e error
		gk, e = groupKey(item, this.plan.Keys(), context)
		if e != nil {
			context.Fatal(errors.NewEvaluationError(e, "GROUP key"))
			return false
		}
	}

	// Get or seed the group value
	gv := this.groups[gk]
	if gv != nil {
		context.Fatal(errors.NewDuplicateFinalGroupError())
		return false
	}

	gv = item
	this.groups[gk] = gv

	// Compute final aggregates
	aggregates := gv.GetAttachment("aggregates")
	switch aggregates := aggregates.(type) {
	case map[string]value.Value:
		for _, agg := range this.plan.Aggregates() {
			v, e := agg.ComputeFinal(aggregates[agg.String()], context)
			if e != nil {
				context.Fatal(errors.NewGroupUpdateError(
					e, "Error updating final GROUP value."))
				return false
			}

			aggregates[agg.String()] = v
		}

		return true
	default:
		context.Fatal(errors.NewInvalidValueError(fmt.Sprintf(
			"Invalid or missing aggregates of type %T.", aggregates)))
		return false
	}
}