restic/vendor/cloud.google.com/go/bigquery/extract.go

// Copyright 2016 Google Inc. All Rights Reserved.
//
// 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
//
//      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 bigquery

import (
	"golang.org/x/net/context"
	bq "google.golang.org/api/bigquery/v2"
)

// ExtractConfig holds the configuration for an extract job.
type ExtractConfig struct {
	// JobID is the ID to use for the job. If empty, a random job ID will be generated.
	JobID string

	// If AddJobIDSuffix is true, then a random string will be appended to JobID.
	AddJobIDSuffix bool

	// Src is the table from which data will be extracted.
	Src *Table

	// Dst is the destination into which the data will be extracted.
	Dst *GCSReference

	// DisableHeader disables the printing of a header row in exported data.
	DisableHeader bool
}

// An Extractor extracts data from a BigQuery table into Google Cloud Storage.
type Extractor struct {
	ExtractConfig
	c *Client
}

// ExtractorTo returns an Extractor which can be used to extract data from a
// BigQuery table into Google Cloud Storage.
// The returned Extractor may optionally be further configured before its Run method is called.
func (t *Table) ExtractorTo(dst *GCSReference) *Extractor {
	return &Extractor{
		c: t.c,
		ExtractConfig: ExtractConfig{
			Src: t,
			Dst: dst,
		},
	}
}

// Run initiates an extract job.
func (e *Extractor) Run(ctx context.Context) (*Job, error) {
	var printHeader *bool
	if e.DisableHeader {
		f := false
		printHeader = &f
	}
	job := &bq.Job{
		JobReference: createJobRef(e.JobID, e.AddJobIDSuffix, e.c.projectID),
		Configuration: &bq.JobConfiguration{
			Extract: &bq.JobConfigurationExtract{
				DestinationUris:   append([]string{}, e.Dst.uris...),
				Compression:       string(e.Dst.Compression),
				DestinationFormat: string(e.Dst.DestinationFormat),
				FieldDelimiter:    e.Dst.FieldDelimiter,
				SourceTable:       e.Src.tableRefProto(),
				PrintHeader:       printHeader,
			},
		},
	}
	return e.c.insertJob(ctx, &insertJobConf{job: job})
}