Class GmailAttachment

Page Summary

A GmailAttachment is a Blob with an extragetSize() method that is faster and does not count against the Gmail read quota.
You can retrieve information about Gmail attachments, such as name and size, using provided methods.
ThegetSize() andgetHash() methods for Gmail attachments do not count against the Gmail read quota and require specific authorization scopes.
Several methods are available for interacting with the data of a Gmail attachment, including getting and setting the data as bytes or strings, and converting to different content types.
ThegetAllBlobs() method for Gmail attachments is deprecated and should not be used in new scripts.

GmailAttachment

An attachment from Gmail. This is a regularBlob except that it has an extragetSize() method that is faster than callinggetBytes().length and does not count against the Gmail read quota.

// Logs information about any attachments in the first 100 inbox threads.constthreads=GmailApp.getInboxThreads(0,100);constmsgs=GmailApp.getMessagesForThreads(threads);for(leti=0;i <msgs.length;i++){for(letj=0;j <msgs[i].length;j++){constattachments=msgs[i][j].getAttachments();for(letk=0;k <attachments.length;k++){Logger.log('Message "%s" contains the attachment "%s" (%s bytes)',msgs[i][j].getSubject(),attachments[k].getName(),attachments[k].getSize(),);}}}

Methods

Method	Return type	Brief description
`copyBlob()`	`Blob`	Returns a copy of this blob.
`getAs(contentType)`	`Blob`	Return the data inside this object as a blob converted to the specified content type.
`getBytes()`	`Byte[]`	Gets the data stored in this blob.
`getContentType()`	`String`	Gets the content type of the bytes in this blob.
`getDataAsString()`	`String`	Gets the data of this blob as a String with UTF-8 encoding.
`getDataAsString(charset)`	`String`	Gets the data of this blob as a string with the specified encoding.
`getHash()`	`String`	Gets the SHA1 content hash for this attachment.
`getName()`	`String`	Gets the name of this blob.
`getSize()`	`Integer`	Gets the size of this attachment.
`isGoogleType()`	`Boolean`	Returns whether this blob is a Google Workspace file (Sheets, Docs, etc.).
`setBytes(data)`	`Blob`	Sets the data stored in this blob.
`setContentType(contentType)`	`Blob`	Sets the content type of the bytes in this blob.
`setContentTypeFromExtension()`	`Blob`	Sets the content type of the bytes in this blob based on the file extension.
`setDataFromString(string)`	`Blob`	Sets the data of this blob from a string with UTF-8 encoding.
`setDataFromString(string, charset)`	`Blob`	Sets the data of this blob from a string with the specified encoding.
`setName(name)`	`Blob`	Sets the name of this blob.

Deprecated methods

Method	Return type	Brief description
`getAllBlobs()`	`Blob[]`	Gets all the blobs that are contained within this (possibly composite) blob.

Detailed documentation

`copyBlob()`

Returns a copy of this blob.

Return

Blob — The new copy.

`getAs(contentType)`

Return the data inside this object as a blob converted to the specified content type. Thismethod adds the appropriate extension to the filename—for example, "myfile.pdf". However, itassumes that the part of the filename that follows the last period (if any) is an existingextension that should be replaced. Consequently, "ShoppingList.12.25.2014" becomes"ShoppingList.12.25.pdf".

To view the daily quotas for conversions, seeQuotas for GoogleServices. Newly created Google Workspace domains might be temporarily subject to stricterquotas.

Parameters

Name	Type	Description
`contentType`	`String`	The MIME type to convert to. For most blobs,`'application/pdf'` is the only valid option. For images in BMP, GIF, JPEG, or PNG format, any of`'image/bmp'`,`'image/gif'`,`'image/jpeg'`, or`'image/png'` are also valid. For a Google Docs document,`'text/markdown'` is also valid.

Return

Blob — The data as a blob.

`getBytes()`

Gets the data stored in this blob.

Return

Byte[] — The stored bytes.

`getContentType()`

Gets the content type of the bytes in this blob.

Return

String — The content type of this data, if known, ornull.

`getDataAsString()`

Gets the data of this blob as a String with UTF-8 encoding.

Return

String — The data as a string.

`getDataAsString(charset)`

Gets the data of this blob as a string with the specified encoding.

Parameters

Name	Type	Description
`charset`	`String`	The charset to use in encoding the data in this blob as a string.

Return

String — The data as a string.

`getHash()`

Gets the SHA1 content hash for this attachment. This method does not count against the Gmailread quota.

Return

String — The SHA1 content hash, as a string.

Authorization

Scripts that use this method require authorization with one or more of the followingscopes or appropriate scopes from therelated REST API:

https://mail.google.com/

`getName()`

Gets the name of this blob.

Return

String — The name of this data, if known, ornull.

`getSize()`

Gets the size of this attachment. This method is faster than callinggetBytes().length and does not count against the Gmail read quota.

Return

Integer — The size of the attachment, in bytes.

Authorization

Scripts that use this method require authorization with one or more of the followingscopes or appropriate scopes from therelated REST API:

https://mail.google.com/

`isGoogleType()`

Returns whether this blob is a Google Workspace file (Sheets, Docs, etc.).

Return

Boolean —true if this blob is a Google Workspace file;false if not.

`setBytes(data)`

Sets the data stored in this blob.