google-drive-wrapper

Wrapper to simplify transferring files to/from google drive.

The npm google-auth-wrapper (npm/ github) can be used to get the credentials required to access your google drive account.

By default it both compresses and encrypts files as they are transferred to google drive. If compressed/encrypted they are decrypted/decompressed as they are download from google drive. Before using please ensure you have validated that the encryption is suitable for the data you are protecting and that you have verified the implementation.

This modules provides these methods:

• gdriveWrapper
• uploadFile
• downloadFile
• downloadNewFiles
• uploadNewFiles
• getMetaForFilename
• getFileMetaData
• listFiles

They allow individual files to be uploaded/download and the contents of directories to be uploaded and downloaded. On upload they allow a file to be converted into a google doc format for sharing/editing in the same manner as any other googlo doc.

As examples, the following use the uploadNewFiles, downloadNewFiles and uploadFile methods (of course use your own passwords, not the ones shown!). See the info for google-auth-wrapper for how to create the required 'client_secret.json' and 'client_secret.token' files:

This example downloads all files in the google drive file 'backups' into the local directory 'download':

This example uploads all files from the local directory 'upload' to the google drive directory 'backups'. Once transferred files are moved from the 'upload' directory to the 'upload-done' directory.

This example uploads a text file and specifies that it should be converted into a google doc document that can be edited online like any other google doc:

We need to disable both compression and encryption as we want the file to be plaintext so it can be converted. We then need to specify 'convert: true' so that the file will be converted on upload, and then we need to specify the mimeType for the type we want it to be convered to. In the case of the example we use 'application/vnd.google-apps.document' to ask that it be converted to a google gdoc document.

Methods

gdriveWrapper

gdriveWrapper is used to create a new wrapper instance that can be used to invoke the other methods. It takes the following parameters:

• auth - googleAuth.OAuth2 object to be used to access the google services
• google - instance of googleapis to be used to access the google services
• password - password from which the key used to encrypt/decrypt the files will be derived.

uploadFile

uploadFile takes the following arguments:

• filename - name of the file to be used in google drive
• sourceFile - name of the local file to be uploaded OR a stream for the file to be uploaded. If a stream is provided the mime type for the source will be 'application/octet-stream'
• options - object as described below
• complete - function to be called when upload is complete or an error occurs. The first parameter will be err. err will either be null if the upload was succesful or an Error object with information as to why the upload failed. If successful the second parameter will be the google meta object for the file uploaded.

The options object can optionally have the following fields:

• encrypt - if true file is encrypted, if false it is not. Default is to encrypt
• compress - if true file is compressed, if false it is not. Default is to compress
• parent - google file id for the parent directory into which the file will be uploaded
• convert - set to true to ask that the file be converted to a google doc on uploaded (optional, default is not to convert)
• mimeType - mime type for the type of google doc that the file should be converted to if 'convert: true' was specified (required if convert is set to true, otherwise ignored)

downloadFile

downloadFile takes the following arguments:

• filedId - google id of the file to be downloaded. You can get this id for a particular path using getMetaForFileName()
• destFilename - name for the file on the local filesystem
• complete - function to be called when download is complete or an error occurs. The first parameter will be err. err will either be null if the download was succesful or an Error object with information as to why the downlaod failed. If successful the second paratmer will be the google meta object for the file downloaded.

If the name of the file with the specified google Id ends with the '.enc' file extension downloadFile will attempt to decrypt during the download. Similarly if the file ends with '.gz.enc' or '.gz' then downloadFile will attempt decompress the file during the download. (Its still a TODO to make this optional). If decrypted and/or decompressed the '.enc' and/or '.gz' extensions will be removed.

downloadNewFiles

Downloads all of the files from the specific google drive folder to a local directory. downloadNewFiles uses a file called '.existing' in the local download directory to track files by their google file id. Once downloaded succesfully the file will not be downloaded again unless you specify a different local download directory or deleete the '.existing' file in the local download directory.

The download files will be named both by their file name in from the file metadata as well as the google file id. This is required because multiple files in the same folder can have the same file name in the meta data. The local files are named as:

each file will be decrypted and or decompressed based on its file name as described for downloadFile() above.

downloadNewFiles takes the following arguments:

• gdriveDirectory - directory path in google drive, this will be converted to a google drive file id by getMetaForFilename()
• targetDirectory - the local directory to which files will be downloaded
• complete - function to be called when download is complete or an error occurs. The first parameter will be err. err will either be null if the download was succesful or an Error object with information as to why the downlaod failed. If there was an error, if available the second parameter will be the fileName associated with the error

uploadNewFiles

Uploads all files from a local directory in to a folder in google drive.

As files are uploaded each file will be encrypted and or compressed as described for uploadFile() above. (still a TODO to make this optional for uploadNewFiles()).

uploadNewFiles takes the following arguments:

• gdriveDirectory - folder in google drive to upload files into, will be converted into google file id using getMetaForFileName().
• sourceDirectory - local directory with the files to upload
• moveTo - directory to which files are moved to after they have been uploaded. Once the upload is complete the result is that all of the files in sourceDirectory should have been uploaded and moved to the moveTo directory
• complete - function to be called when upload is complete or an error occurs. The first parameter will be err. err will either be null if the upload was succesful or an Error object with information as to why the upload failed.

getMetaForFilename

Converts a path like name to a google file id. Finds the google file id for each segment and then limits search in next segement to the the file id for the previous segment. It will find the fist occurance of a file whoes filename matches a segment. Since multiple files with the same parent can have the same filename in their metadata this may not always get the file you expect. It is up to you to make sure you manage the naming of the parents so that the name you pass in will resolve to the expected google file id. For example if you resolve:

you will need to make sure that only one file has the filename 'level1' at the root of your drive and that only one child of 'level1' is named 'level2'.

getMetaForFilename takes the following arguments:

• filename - path like file name to be resolved
• complete - function to be called when resolution is complete or an error occurs The first parameter will be err. err will either be null if the resolution was succesful or an Error object with information as to why the resolution failed. If there is an error then if available, the second parameter will be the file that the meta was requested for. If successful the second parameter will be the google drive metadata object for file matching the file specified.

getFileMetaData

Returns the metadata for a file give the google drive file id.

getFileMetaData takes the following arguments:

• fileId - file id for the file
• complete - function to be called when resolution is complete or an error occurs The first parameter will be err. err will either be null if the resolution was succesful or an Error object with information as to why the resolution failed. If successful the second parameter will be the google drive metadata object for file matching the file specified.

listFiles

Passes an array of metadata to the completion handler with one entry for each regular file in the path specified.

listFiles takes the following arguments:

• gdriveDirectory - folder in google drive to list the contents of, will be converted into google file id using getMetaForFileName().
• complete - function to be called with the result or if an error occurs. The first parameter will be err. err will either be null if successfull or an Error object with information about the error that occurred. If successful the second parameter will be the array of metadata, one for each regular file in the path specified.