gdf: Google Drive Find -- Search for a file in Google Drive using a service account and the (Golang) Google Drive API (v3)

gdf.go

package main

import (
   "fmt"
   "github.com/dustin/go-humanize"
   "golang.org/x/oauth2"
   "golang.org/x/oauth2/google"
   "google.golang.org/api/drive/v3"
   "io/ioutil"
   "log"
   "net/http"
   "os"
   "strings"
   "time"
)

// Quick & dirty CLI tool to see if a file exists in Google Drive
//
// Usage:
//      $ gdf <string or strings>
//
// Example Usage:
//      $ gdf Queen Elizabeth II
//      | 3.9 MB| Queen Elizabeth II (popart).png
//      $ gdf foobarbaz.png
//      No files found.
//
// Notes:
//      1) The service account will need to be granted 'drivescope' in the Admin Console. To grant this, go to
//         'Admin Console --> Security --> Advanced Settings --> Manage API Client Access'
//      2) Drive API will need to be enabled in the service account's GCP project
//      3) Service account will need to be granted Domain-wide Delegation authority.
//         See https://developers.google.com/admin-sdk/directory/v1/guides/delegation for more info.

const (
   credsfile  string = "credentials.json"
   drivescope string = "https://www.googleapis.com/auth/drive.readonly"
   pagesize   int64  = 1000
   who        string = "you@you.com"
)

// Get an authenticated http client
func httpclient(creds []byte) (*http.Client, error) {
   conf, err := google.JWTConfigFromJSON(creds, drivescope)
   if err != nil {
      return nil, err
   }
   conf.Subject = who
   return conf.Client(oauth2.NoContext), nil
}

func main() {
   if len(os.Args) < 2 {
      log.Fatalf("error: no search criteria specified")
   }
   // Load the JSON credentials
   creds, err := ioutil.ReadFile(credsfile)
   if err != nil {
      log.Fatalf("error reading credentials file: %s", err)
   }

   // Get an authenticated http client
   client, err := httpclient(creds)
   if err != nil {
      log.Fatalf("error getting authenticated http client: %s", err)
   }

   // Get a Drive client
   dc, err := drive.New(client)
   if err != nil {
      log.Fatalf("Unable to get a Drive client: %v", err)
   }

   // Search for files with filenames containing argv[1:]
   files, err := dc.Files.List().
      Fields("nextPageToken, files(id, mimeType, modifiedTime, name, size)").
      PageSize(pagesize).
      Q("name contains '" + strings.Join(os.Args[1:], " ") + "'").
      SupportsAllDrives(true).
      Do()
   if err != nil {
      log.Fatalf("Unable to retrieve files: %v", err)
   }
   if len(files.Files) == 0 {
      fmt.Println("No files found.")
   } else {
      for _, i := range files.Files {
         // Get the last modified time
         lmt, err := time.Parse(time.RFC3339, i.ModifiedTime)
         if err != nil {
            log.Fatalf("error converting last modified time: %s", err)
         }
         if i.MimeType == "application/vnd.google-apps.folder" {
            fmt.Printf("|%8s |%14s | %s\n", "folder", humanize.Time(lmt), i.Name)
         } else {
            fmt.Printf("|%8s |%14s | %s\n", humanize.Bytes(uint64(i.Size)), humanize.Time(lmt), i.Name)
         }
      }
   }
   return
}

// EOF