rclone/vendor/cloud.google.com/go/bigquery/dataset.go
2017-09-30 15:27:27 +01:00

247 lines
8.3 KiB
Go

// Copyright 2015 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 (
"time"
"cloud.google.com/go/internal/optional"
"golang.org/x/net/context"
"google.golang.org/api/iterator"
)
// Dataset is a reference to a BigQuery dataset.
type Dataset struct {
ProjectID string
DatasetID string
c *Client
}
// DatasetMetadata contains information about a BigQuery dataset.
type DatasetMetadata struct {
// These fields can be set when creating a dataset.
Name string // The user-friendly name for this dataset.
Description string // The user-friendly description of this dataset.
Location string // The geo location of the dataset.
DefaultTableExpiration time.Duration // The default expiration time for new tables.
Labels map[string]string // User-provided labels.
// These fields are read-only.
CreationTime time.Time
LastModifiedTime time.Time // When the dataset or any of its tables were modified.
FullID string // The full dataset ID in the form projectID:datasetID.
// ETag is the ETag obtained when reading metadata. Pass it to Dataset.Update to
// ensure that the metadata hasn't changed since it was read.
ETag string
// TODO(jba): access rules
}
// DatasetMetadataToUpdate is used when updating a dataset's metadata.
// Only non-nil fields will be updated.
type DatasetMetadataToUpdate struct {
Description optional.String // The user-friendly description of this table.
Name optional.String // The user-friendly name for this dataset.
// DefaultTableExpiration is the the default expiration time for new tables.
// If set to time.Duration(0), new tables never expire.
DefaultTableExpiration optional.Duration
setLabels map[string]string
deleteLabels map[string]bool
}
// SetLabel causes a label to be added or modified when dm is used
// in a call to Dataset.Update.
func (dm *DatasetMetadataToUpdate) SetLabel(name, value string) {
if dm.setLabels == nil {
dm.setLabels = map[string]string{}
}
dm.setLabels[name] = value
}
// DeleteLabel causes a label to be deleted when dm is used in a
// call to Dataset.Update.
func (dm *DatasetMetadataToUpdate) DeleteLabel(name string) {
if dm.deleteLabels == nil {
dm.deleteLabels = map[string]bool{}
}
dm.deleteLabels[name] = true
}
// Dataset creates a handle to a BigQuery dataset in the client's project.
func (c *Client) Dataset(id string) *Dataset {
return c.DatasetInProject(c.projectID, id)
}
// DatasetInProject creates a handle to a BigQuery dataset in the specified project.
func (c *Client) DatasetInProject(projectID, datasetID string) *Dataset {
return &Dataset{
ProjectID: projectID,
DatasetID: datasetID,
c: c,
}
}
// Create creates a dataset in the BigQuery service. An error will be returned if the
// dataset already exists. Pass in a DatasetMetadata value to configure the dataset.
func (d *Dataset) Create(ctx context.Context, md *DatasetMetadata) error {
return d.c.service.insertDataset(ctx, d.DatasetID, d.ProjectID, md)
}
// Delete deletes the dataset.
func (d *Dataset) Delete(ctx context.Context) error {
return d.c.service.deleteDataset(ctx, d.DatasetID, d.ProjectID)
}
// Metadata fetches the metadata for the dataset.
func (d *Dataset) Metadata(ctx context.Context) (*DatasetMetadata, error) {
return d.c.service.getDatasetMetadata(ctx, d.ProjectID, d.DatasetID)
}
// Update modifies specific Dataset metadata fields.
// To perform a read-modify-write that protects against intervening reads,
// set the etag argument to the DatasetMetadata.ETag field from the read.
// Pass the empty string for etag for a "blind write" that will always succeed.
func (d *Dataset) Update(ctx context.Context, dm DatasetMetadataToUpdate, etag string) (*DatasetMetadata, error) {
return d.c.service.patchDataset(ctx, d.ProjectID, d.DatasetID, &dm, etag)
}
// Table creates a handle to a BigQuery table in the dataset.
// To determine if a table exists, call Table.Metadata.
// If the table does not already exist, use Table.Create to create it.
func (d *Dataset) Table(tableID string) *Table {
return &Table{ProjectID: d.ProjectID, DatasetID: d.DatasetID, TableID: tableID, c: d.c}
}
// Tables returns an iterator over the tables in the Dataset.
func (d *Dataset) Tables(ctx context.Context) *TableIterator {
it := &TableIterator{
ctx: ctx,
dataset: d,
}
it.pageInfo, it.nextFunc = iterator.NewPageInfo(
it.fetch,
func() int { return len(it.tables) },
func() interface{} { b := it.tables; it.tables = nil; return b })
return it
}
// A TableIterator is an iterator over Tables.
type TableIterator struct {
ctx context.Context
dataset *Dataset
tables []*Table
pageInfo *iterator.PageInfo
nextFunc func() error
}
// Next returns the next result. Its second return value is Done if there are
// no more results. Once Next returns Done, all subsequent calls will return
// Done.
func (it *TableIterator) Next() (*Table, error) {
if err := it.nextFunc(); err != nil {
return nil, err
}
t := it.tables[0]
it.tables = it.tables[1:]
return t, nil
}
// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *TableIterator) PageInfo() *iterator.PageInfo { return it.pageInfo }
func (it *TableIterator) fetch(pageSize int, pageToken string) (string, error) {
tables, tok, err := it.dataset.c.service.listTables(it.ctx, it.dataset.ProjectID, it.dataset.DatasetID, pageSize, pageToken)
if err != nil {
return "", err
}
for _, t := range tables {
t.c = it.dataset.c
it.tables = append(it.tables, t)
}
return tok, nil
}
// Datasets returns an iterator over the datasets in a project.
// The Client's project is used by default, but that can be
// changed by setting ProjectID on the returned iterator before calling Next.
func (c *Client) Datasets(ctx context.Context) *DatasetIterator {
return c.DatasetsInProject(ctx, c.projectID)
}
// DatasetsInProject returns an iterator over the datasets in the provided project.
//
// Deprecated: call Client.Datasets, then set ProjectID on the returned iterator.
func (c *Client) DatasetsInProject(ctx context.Context, projectID string) *DatasetIterator {
it := &DatasetIterator{
ctx: ctx,
c: c,
ProjectID: projectID,
}
it.pageInfo, it.nextFunc = iterator.NewPageInfo(
it.fetch,
func() int { return len(it.items) },
func() interface{} { b := it.items; it.items = nil; return b })
return it
}
// DatasetIterator iterates over the datasets in a project.
type DatasetIterator struct {
// ListHidden causes hidden datasets to be listed when set to true.
// Set before the first call to Next.
ListHidden bool
// Filter restricts the datasets returned by label. The filter syntax is described in
// https://cloud.google.com/bigquery/docs/labeling-datasets#filtering_datasets_using_labels
// Set before the first call to Next.
Filter string
// The project ID of the listed datasets.
// Set before the first call to Next.
ProjectID string
ctx context.Context
c *Client
pageInfo *iterator.PageInfo
nextFunc func() error
items []*Dataset
}
// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *DatasetIterator) PageInfo() *iterator.PageInfo { return it.pageInfo }
func (it *DatasetIterator) Next() (*Dataset, error) {
if err := it.nextFunc(); err != nil {
return nil, err
}
item := it.items[0]
it.items = it.items[1:]
return item, nil
}
func (it *DatasetIterator) fetch(pageSize int, pageToken string) (string, error) {
datasets, nextPageToken, err := it.c.service.listDatasets(it.ctx, it.ProjectID,
pageSize, pageToken, it.ListHidden, it.Filter)
if err != nil {
return "", err
}
for _, d := range datasets {
d.c = it.c
it.items = append(it.items, d)
}
return nextPageToken, nil
}