jrmccluskey commented on a change in pull request #15253: URL: https://github.com/apache/beam/pull/15253#discussion_r680013819
########## File path: sdks/go/pkg/beam/testing/teststream/teststream.go ########## @@ -0,0 +1,131 @@ +// Licensed to the Apache Software Foundation (ASF) under one or more +// contributor license agreements. See the NOTICE file distributed with +// this work for additional information regarding copyright ownership. +// The ASF licenses this file to You under the Apache License, Version 2.0 +// (the "License"); you may not use this file except in compliance with +// the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package teststream contains code configuring the TestStream primitive for +// use in testing code that is meant to be run on streaming data sources. +// TestStream is not supported on the Go direct runner. +package teststream + +import ( + "bytes" + "fmt" + + "github.com/apache/beam/sdks/go/pkg/beam" + "github.com/apache/beam/sdks/go/pkg/beam/core/graph/coder" + "github.com/apache/beam/sdks/go/pkg/beam/core/graph/mtime" + "github.com/apache/beam/sdks/go/pkg/beam/core/util/protox" + + pipepb "github.com/apache/beam/sdks/go/pkg/beam/model/pipeline_v1" +) + +const urn = "beam:transform:teststream:v1" + +// Config holds information used to create a TestStreamPayload object. +type Config struct { + ElmCoder *coder.Coder + Events []*pipepb.TestStreamPayload_Event + Endpoint *pipepb.ApiServiceDescriptor + Watermark int64 +} + +// MakeConfig initializes a Config struct to begin inserting TestStream events/endpoints into. +// Requires that users provide the coder for the elements they are trying to emit. +func MakeConfig(c *coder.Coder) Config { + return Config{ElmCoder: c, + Events: []*pipepb.TestStreamPayload_Event{}, + Endpoint: &pipepb.ApiServiceDescriptor{}, + Watermark: 0, + } +} + +// SetEndpoint sets a URL for a TestStreamService that will emit events instead of having them +// defined manually. Currently does not support authentication, so the TestStreamService should +// be accessed in a trusted context. +func (c *Config) SetEndpoint(url string) { + c.Endpoint.Url = url +} + +// CreatePayload converts the Config object into a TestStreamPayload to be sent to the runner. +func (c *Config) CreatePayload() *pipepb.TestStreamPayload { + return &pipepb.TestStreamPayload{CoderId: "c0", Events: c.Events, Endpoint: c.Endpoint} +} + +// AdvanceWatermark adds an event to the Config Events struct advancing the watermark for a PCollection +// to the given timestamp. if the tag is empty, this is applied to the default PCollection. Timestamp is +// in milliseconds +func (c *Config) AdvanceWatermark(timestamp int64) error { + if c.Watermark >= timestamp { + return fmt.Errorf("watermark must be monotonally increasing, is at %v, got %v", c.Watermark, timestamp) + } + watermarkAdvance := &pipepb.TestStreamPayload_Event_AdvanceWatermark{NewWatermark: timestamp} + watermarkEvent := &pipepb.TestStreamPayload_Event_WatermarkEvent{WatermarkEvent: watermarkAdvance} + c.Events = append(c.Events, &pipepb.TestStreamPayload_Event{Event: watermarkEvent}) + c.Watermark = timestamp + return nil +} + +// AdvanceWatermarkToInfinity advances the watermark for the PCollection corresponding to the tag +// to the maximum timestamp. +func (c *Config) AdvanceWatermarkToInfinity() error { + return c.AdvanceWatermark(mtime.MaxTimestamp.Milliseconds()) +} + +// AdvanceProcessingTime adds an event into the Config Events struct advancing the processing time by a given +// duration. This advancement is applied to all of the PCollections output by the TestStream. +func (c *Config) AdvanceProcessingTime(duration int64) { + processingAdvance := &pipepb.TestStreamPayload_Event_AdvanceProcessingTime{AdvanceDuration: duration} + processingEvent := &pipepb.TestStreamPayload_Event_ProcessingTimeEvent{ProcessingTimeEvent: processingAdvance} + c.Events = append(c.Events, &pipepb.TestStreamPayload_Event{Event: processingEvent}) +} + +// AdvanceProcessingTimeToInfinity moves the TestStream processing time to the largest possible +// timestamp. +func (c *Config) AdvanceProcessingTimeToInfinity() { + c.AdvanceProcessingTime(mtime.MaxTimestamp.Milliseconds()) +} + +// AddElements adds a number of elements to the Config object at the specified timestamp. +// The encoder will panic if there is a type mismatch between the provided coder and the +// elements. +func (c *Config) AddElements(timestamp int64, elements ...interface{}) error { + newElements := []*pipepb.TestStreamPayload_TimestampedElement{} + enc := beam.NewElementEncoder(c.ElmCoder.T.Type()) + for _, e := range elements { + var buf bytes.Buffer + if err := enc.Encode(e, &buf); err != nil { + return fmt.Errorf("encoding value %v failed, got %v", e, err) + } + newElements = append(newElements, &pipepb.TestStreamPayload_TimestampedElement{EncodedElement: buf.Bytes(), Timestamp: timestamp}) + } + addElementsEvent := &pipepb.TestStreamPayload_Event_AddElements{Elements: newElements} + elementEvent := &pipepb.TestStreamPayload_Event_ElementEvent{ElementEvent: addElementsEvent} + c.Events = append(c.Events, &pipepb.TestStreamPayload_Event{Event: elementEvent}) + return nil +} + +// TestStream inserts a TestStream primitive into a pipeline, taking a scope and a Config object and +// producing an array of output PCollections. +func TestStream(s beam.Scope, c Config) []beam.PCollection { + pyld := protox.MustEncode(c.CreatePayload()) + outputs := []beam.FullType{c.ElmCoder.T} + + outputMap := beam.External(s, urn, pyld, []beam.PCollection{}, outputs, false) + + var ret []beam.PCollection + for _, val := range outputMap { + ret = append(ret, val) + } + return ret Review comment: This should only ever be a single PCollection, so I was thinking this should be changed so that the return type is just a beam.PCollection, but didn't know if there was a clean looking way to do that. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
