| // 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. |
| |
| // read is an example client of the bigquery client library. |
| // It reads from a table, returning the data via an Iterator. |
| package main |
| |
| import ( |
| "flag" |
| "fmt" |
| "log" |
| "os" |
| "regexp" |
| "strings" |
| "text/tabwriter" |
| |
| "golang.org/x/net/context" |
| "google.golang.org/cloud/bigquery" |
| ) |
| |
| var ( |
| project = flag.String("project", "", "The ID of a Google Cloud Platform project") |
| dataset = flag.String("dataset", "", "The ID of a BigQuery dataset") |
| table = flag.String("table", ".*", "A regular expression to match the IDs of tables to read.") |
| jobID = flag.String("jobid", "", "The ID of a query job that has already been submitted."+ |
| " If set, --dataset, --table will be ignored, and results will be read from the specified job.") |
| ) |
| |
| func printValues(ctx context.Context, it *bigquery.Iterator) { |
| // one-space padding. |
| tw := tabwriter.NewWriter(os.Stdout, 0, 0, 1, ' ', 0) |
| |
| for it.Next(ctx) { |
| var vals bigquery.ValueList |
| if err := it.Get(&vals); err != nil { |
| fmt.Printf("err calling get: %v\n", err) |
| } else { |
| sep := "" |
| for _, v := range vals { |
| fmt.Fprintf(tw, "%s%v", sep, v) |
| sep = "\t" |
| } |
| fmt.Fprintf(tw, "\n") |
| } |
| } |
| tw.Flush() |
| |
| fmt.Printf("\n") |
| if err := it.Err(); err != nil { |
| fmt.Printf("err reading: %v\n", err) |
| } |
| } |
| |
| func printTable(ctx context.Context, client *bigquery.Client, t *bigquery.Table) { |
| it, err := client.Read(ctx, t) |
| if err != nil { |
| log.Fatalf("Reading: %v", err) |
| } |
| |
| id := t.FullyQualifiedName() |
| fmt.Printf("%s\n%s\n", id, strings.Repeat("-", len(id))) |
| printValues(ctx, it) |
| } |
| |
| func printQueryResults(ctx context.Context, client *bigquery.Client, queryJobID string) { |
| job, err := client.JobFromID(ctx, queryJobID) |
| if err != nil { |
| log.Fatalf("Loading job: %v", err) |
| } |
| |
| it, err := client.Read(ctx, job) |
| if err != nil { |
| log.Fatalf("Reading: %v", err) |
| } |
| |
| // TODO: print schema. |
| printValues(ctx, it) |
| } |
| |
| func main() { |
| flag.Parse() |
| |
| flagsOk := true |
| if flag.Lookup("project").Value.String() == "" { |
| fmt.Fprintf(os.Stderr, "Flag --project is required\n") |
| flagsOk = false |
| } |
| |
| var sourceFlagCount int |
| if flag.Lookup("dataset").Value.String() != "" { |
| sourceFlagCount++ |
| } |
| if flag.Lookup("jobid").Value.String() != "" { |
| sourceFlagCount++ |
| } |
| if sourceFlagCount != 1 { |
| fmt.Fprintf(os.Stderr, "Exactly one of --dataset or --jobid must be set\n") |
| flagsOk = false |
| } |
| |
| if !flagsOk { |
| os.Exit(1) |
| } |
| |
| ctx := context.Background() |
| tableRE, err := regexp.Compile(*table) |
| if err != nil { |
| fmt.Fprintf(os.Stderr, "--table is not a valid regular expression: %q\n", *table) |
| os.Exit(1) |
| } |
| |
| client, err := bigquery.NewClient(ctx, *project) |
| if err != nil { |
| log.Fatalf("Creating bigquery client: %v", err) |
| } |
| |
| if *jobID != "" { |
| printQueryResults(ctx, client, *jobID) |
| return |
| } |
| ds := client.Dataset(*dataset) |
| var tables []*bigquery.Table |
| tables, err = ds.ListTables(context.Background()) |
| if err != nil { |
| log.Fatalf("Listing tables: %v", err) |
| } |
| for _, t := range tables { |
| if tableRE.MatchString(t.TableID) { |
| printTable(ctx, client, t) |
| } |
| } |
| } |