1// Copyright 2016 Google LLC
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//      http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package bigquery
16
17import (
18	"context"
19
20	bq "google.golang.org/api/bigquery/v2"
21)
22
23// CopyConfig holds the configuration for a copy job.
24type CopyConfig struct {
25	// Srcs are the tables from which data will be copied.
26	Srcs []*Table
27
28	// Dst is the table into which the data will be copied.
29	Dst *Table
30
31	// CreateDisposition specifies the circumstances under which the destination table will be created.
32	// The default is CreateIfNeeded.
33	CreateDisposition TableCreateDisposition
34
35	// WriteDisposition specifies how existing data in the destination table is treated.
36	// The default is WriteEmpty.
37	WriteDisposition TableWriteDisposition
38
39	// The labels associated with this job.
40	Labels map[string]string
41
42	// Custom encryption configuration (e.g., Cloud KMS keys).
43	DestinationEncryptionConfig *EncryptionConfig
44}
45
46func (c *CopyConfig) toBQ() *bq.JobConfiguration {
47	var ts []*bq.TableReference
48	for _, t := range c.Srcs {
49		ts = append(ts, t.toBQ())
50	}
51	return &bq.JobConfiguration{
52		Labels: c.Labels,
53		Copy: &bq.JobConfigurationTableCopy{
54			CreateDisposition:                  string(c.CreateDisposition),
55			WriteDisposition:                   string(c.WriteDisposition),
56			DestinationTable:                   c.Dst.toBQ(),
57			DestinationEncryptionConfiguration: c.DestinationEncryptionConfig.toBQ(),
58			SourceTables:                       ts,
59		},
60	}
61}
62
63func bqToCopyConfig(q *bq.JobConfiguration, c *Client) *CopyConfig {
64	cc := &CopyConfig{
65		Labels:                      q.Labels,
66		CreateDisposition:           TableCreateDisposition(q.Copy.CreateDisposition),
67		WriteDisposition:            TableWriteDisposition(q.Copy.WriteDisposition),
68		Dst:                         bqToTable(q.Copy.DestinationTable, c),
69		DestinationEncryptionConfig: bqToEncryptionConfig(q.Copy.DestinationEncryptionConfiguration),
70	}
71	for _, t := range q.Copy.SourceTables {
72		cc.Srcs = append(cc.Srcs, bqToTable(t, c))
73	}
74	return cc
75}
76
77// A Copier copies data into a BigQuery table from one or more BigQuery tables.
78type Copier struct {
79	JobIDConfig
80	CopyConfig
81	c *Client
82}
83
84// CopierFrom returns a Copier which can be used to copy data into a
85// BigQuery table from one or more BigQuery tables.
86// The returned Copier may optionally be further configured before its Run method is called.
87func (t *Table) CopierFrom(srcs ...*Table) *Copier {
88	return &Copier{
89		c: t.c,
90		CopyConfig: CopyConfig{
91			Srcs: srcs,
92			Dst:  t,
93		},
94	}
95}
96
97// Run initiates a copy job.
98func (c *Copier) Run(ctx context.Context) (*Job, error) {
99	return c.c.insertJob(ctx, c.newJob(), nil)
100}
101
102func (c *Copier) newJob() *bq.Job {
103	return &bq.Job{
104		JobReference:  c.JobIDConfig.createJobRef(c.c),
105		Configuration: c.CopyConfig.toBQ(),
106	}
107}
108