add support for uploading new sample pipeline vers

This change adds additional sampleconfig options that provide support
for uploading new Pipelines and PipelineVersion samples. To accommodate
this and backwards compatibility the structure of the samples config has
been changed. Configs following the old format will continue to be
supported.

Sample config code is also moved to its own file so as not to bloat
main.go

In order to handle conflicts, and detecting pipeline/pipelineVersion
existence, additional db queries are made per pipeline and pipeline
version at apiserver startup.

Signed-off-by: Humair Khan <[email protected]>

backend/src/apiserver/config/config.go

@@ -0,0 +1,210 @@
+// Copyright 2025 The Kubeflow Authors
+//
+// Licensed 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
+//
+// https://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 config
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/golang/glog"
+	"github.com/kubeflow/pipelines/backend/src/apiserver/client"
+	"github.com/kubeflow/pipelines/backend/src/apiserver/common"
+	"github.com/kubeflow/pipelines/backend/src/apiserver/model"
+	"github.com/kubeflow/pipelines/backend/src/apiserver/resource"
+	"github.com/kubeflow/pipelines/backend/src/apiserver/server"
+	"github.com/kubeflow/pipelines/backend/src/common/util"
+	"google.golang.org/grpc/codes"
+	"os"
+	"time"
+)
+
+// deprecated
+type deprecatedConfig struct {
+	Name        string
+	Description string
+	File        string
+}
+
+type configPipelines struct {
+	Name        string
+	Description string
+	File        string
+	// optional, Name is used for PipelineVersion if not provided
+	VersionName string
+	// optional, Description is used for PipelineVersion if not provided
+	VersionDescription string
+}
+
+type config struct {
+	// If pipeline version already exists and
+	// LoadSamplesOnRestart is enabled, then the pipeline
+	// version is uploaded again on server restart
+	// if it does not already exist
+	LoadSamplesOnRestart bool
+	Pipelines            []configPipelines
+}
+
+// LoadSamples preloads a collection of pipeline samples
+//
+// If LoadSamplesOnRestart is false then Samples are only
+// loaded once when the pipeline system is initially installed.
+// They won't be loaded on upgrade or pod restart, to
+// prevent them from reappearing if user explicitly deletes the
+// samples. If LoadSamplesOnRestart is true then PipelineVersions
+// are uploaded if they do not already exist upon upgrade or pod
+// restart.
+func LoadSamples(resourceManager *resource.ResourceManager, sampleConfigPath string) error {
+	pathExists, err := client.PathExists(sampleConfigPath)
+	if err != nil {
+		return err
+	}
+
+	if !pathExists {
+		glog.Infof("No samples path provided, skipping loading samples..")
+		return nil
+	}
+
+	configBytes, err := os.ReadFile(sampleConfigPath)
+	if err != nil {
+		return fmt.Errorf("failed to read sample configurations file. Err: %v", err)
+	}
+
+	var pipelineConfig config
+	if configErr := json.Unmarshal(configBytes, &pipelineConfig); configErr != nil {
+		// Attempt to parse to deprecated config version:
+		var deprecatedCfg []deprecatedConfig
+		if depConfigErr := json.Unmarshal(configBytes, &deprecatedCfg); depConfigErr != nil {
+			return fmt.Errorf("failed to read sample configurations. Err: %v", configErr)
+		}
+		glog.Warningf("encountered deprecated version of samples config, please update to the newer version to " +
+			"ensure future compatibility")
+		for _, cfg := range deprecatedCfg {
+			pipelineConfig.Pipelines = append(pipelineConfig.Pipelines, configPipelines{
+				Name:        cfg.Name,
+				File:        cfg.File,
+				Description: cfg.Description,
+			})
+		}
+		pipelineConfig.LoadSamplesOnRestart = false
+	}
+
+	// Check if sample has been loaded already and skip loading if true.
+	haveSamplesLoaded, err := resourceManager.HaveSamplesLoaded()
+	if err != nil {
+		return err
+	}
+
+	if !pipelineConfig.LoadSamplesOnRestart && haveSamplesLoaded {
+		glog.Infof("Samples already loaded in the past. Skip loading.")
+		return nil
+	}
+
+	for _, cfg := range pipelineConfig.Pipelines {
+		// Track if this is the first upload of this pipeline
+		var firstUpload = false
+		reader, configErr := os.Open(cfg.File)
+		if configErr != nil {
+			return fmt.Errorf("failed to load sample %s. Error: %v", cfg.Name, configErr)
+		}
+		pipelineFile, configErr := server.ReadPipelineFile(cfg.File, reader, common.MaxFileLength)
+		if configErr != nil {
+			return fmt.Errorf("failed to load sample %s. Error: %v", cfg.Name, configErr)
+		}
+
+		// Create pipeline if it does not already exist
+		p, fetchErr := resourceManager.GetPipelineByNameAndNamespace(cfg.Name, "")
+		if fetchErr != nil {
+			if util.IsUserErrorCodeMatch(fetchErr, codes.NotFound) {
+				p, configErr = resourceManager.CreatePipeline(&model.Pipeline{
+					Name:        cfg.Name,
+					Description: cfg.Description,
+				})
+				if configErr != nil {
+					// Log the error but not fail. The API Server pod can restart and it could potentially cause
+					// name collision. In the future, we might consider loading samples during deployment, instead
+					// of when API server starts.
+					glog.Warningf(fmt.Sprintf(
+						"Failed to create pipeline for %s. Error: %v", cfg.Name, configErr))
+					continue
+				} else {
+					glog.Info(fmt.Sprintf("Successfully uploaded Pipeline %s.", cfg.Name))
+					firstUpload = true
+				}
+			} else {
+				return fmt.Errorf(
+					"Failed to handle load sample for Pipeline: %s. Error: %v", cfg.Name, fetchErr)
+			}
+		}
+
+		// Use Pipeline Version Name/Description if provided
+		// Otherwise fallback to owning Pipeline's Name/Description
+		pvDescription := cfg.Description
+		if cfg.VersionDescription != "" {
+			pvDescription = cfg.VersionDescription
+		}
+		pvName := cfg.Name
+		if cfg.VersionName != "" {
+			pvName = cfg.VersionName
+		}
+
+		// If the Pipeline Version exists, do nothing
+		// Otherwise upload new Pipeline Version for
+		// this pipeline.
+		_, fetchErr = resourceManager.GetPipelineVersionByName(pvName)
+		if fetchErr != nil {
+			if util.IsUserErrorCodeMatch(fetchErr, codes.NotFound) {
+				_, configErr = resourceManager.CreatePipelineVersion(
+					&model.PipelineVersion{
+						Name:         pvName,
+						Description:  pvDescription,
+						PipelineId:   p.UUID,
+						PipelineSpec: string(pipelineFile),
+					},
+				)
+				if configErr != nil {
+					// Log the error but not fail. The API Server pod can restart and it could potentially cause name collision.
+					// In the future, we might consider loading samples during deployment, instead of when API server starts.
+					glog.Warningf(fmt.Sprintf("Failed to create pipeline for %s. Error: %v", pvName, configErr))
+
+					continue
+				} else {
+					glog.Info(fmt.Sprintf("Successfully uploaded PipelineVersion %s.", pvName))
+				}
+
+				if firstUpload {
+					// Since the default sorting is by create time,
+					// Sleep one second makes sure the samples are
+					// showing up in the same order as they are added.
+					time.Sleep(1 * time.Second)
+				}
+			} else {
+				return fmt.Errorf(
+					"Failed to handle load sample for PipelineVersion: %s. Error: %v", pvName, fetchErr)
+			}
+		} else {
+			// pipeline version already exists, do nothing
+			continue
+		}
+	}
+
+	if !haveSamplesLoaded {
+		err = resourceManager.MarkSampleLoaded()
+		if err != nil {
+			return err
+		}
+	}
+
+	glog.Info("All samples are loaded.")
+	return nil
+}