Transloadit

Import files from Amazon S3

🤖/s3/import imports whole directories of files from your S3 bucket.

If you are new to Amazon S3, see our tutorial on using your own S3 bucket.

The URL to the result file in your S3 bucket will be returned in the Assembly Status JSON.

Limit access

You will also need to add permissions to your bucket so that Transloadit can access it properly. Here is an example IAM policy that you can use. Following the principle of least privilege, it contains the minimum required permissions to export a file to your S3 bucket using Transloadit. You may require more permissions (especially viewing permissions) depending on your application.

Please change {BUCKET_NAME} in the values for Sid and Resource accordingly. Also, this policy will grant the minimum required permissions to all your users. We advise you to create a separate Amazon IAM user, and use its User ARN (can be found in the "Summary" tab of a user here) for the Principal value. More information about this can be found here.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "AllowTransloaditToImportFilesIn{BUCKET_NAME}Bucket",
      "Effect": "Allow",
      "Action": ["s3:GetBucketLocation", "s3:ListBucket"],
      "Resource": ["arn:aws:s3:::{BUCKET_NAME}", "arn:aws:s3:::{BUCKET_NAME}/*"]
    }
  ]
}

The Sid value is just an identifier for you to recognize the rule later. You can name it anything you like.

The policy needs to be separated into two parts, because the ListBucket action requires permissions on the bucket while the other actions require permissions on the objects in the bucket. When targeting the objects there's a trailing slash and an asterisk in the Resource parameter, whereas when the policy targets the bucket, the slash and the asterisk are omitted.

In order to build proper result URLs we need to know the region in which your S3 bucket resides. For this we require the GetBucketLocation permission. Figuring out your bucket's region this way will also slow down your Assemblies. To make this much faster and to also not require the GetBucketLocation permission, we have added the bucket_region parameter to the /s3/store and /s3/import Robots. We recommend using them at all times.

Please keep in mind that if you use bucket encryption you may also need to add "sts:*" and "kms:*" to the bucket policy. Please read here and here in case you run into trouble with our example bucket policy.

Usage example

Import files from the path/to/files directory and its subdirectories:

{
  "steps": {
    "imported": {
      "robot": "/s3/import",
      "credentials": "YOUR_AWS_CREDENTIALS",
      "path": "path/to/files/",
      "recursive": true
    }
  }
}

Parameters

  • output_meta

    Record<string, boolean> | boolean | Array<string>

    Allows you to specify a set of metadata that is more expensive on CPU power to calculate, and thus is disabled by default to keep your Assemblies processing fast.

    For images, you can add "has_transparency": true in this object to extract if the image contains transparent parts and "dominant_colors": true to extract an array of hexadecimal color codes from the image.

    For images, you can also add "blurhash": true to extract a BlurHash string — a compact representation of a placeholder for the image, useful for showing a blurred preview while the full image loads.

    For videos, you can add the "colorspace: true" parameter to extract the colorspace of the output video.

    For audio, you can add "mean_volume": true to get a single value representing the mean average volume of the audio file.

    You can also set this to false to skip metadata extraction and speed up transcoding.

  • result

    boolean (default: false)

    Whether the results of this Step should be present in the Assembly Status JSON

  • queue

    batch

    Setting the queue to 'batch', manually downgrades the priority of jobs for this step to avoid consuming Priority job slots for jobs that don't need zero queue waiting times

  • force_accept

    boolean (default: false)

    Force a Robot to accept a file type it would have ignored.

    By default, Robots ignore files they are not familiar with. 🤖/video/encode, for example, will happily ignore input images.

    With the force_accept parameter set to true, you can force Robots to accept all files thrown at them. This will typically lead to errors and should only be used for debugging or combatting edge cases.

  • force_name

    string | Array<string> | null (default: null)

    Custom name for the imported file(s). By default file names are derived from the source.

  • credentials

    string

    Please create your associated Template Credentials in your Transloadit account and use the name of your Template Credentials as this parameter's value. They will contain the values for your S3 bucket, Key, Secret and Bucket region.

    While we recommend to use Template Credentials at all times, some use cases demand dynamic credentials for which using Template Credentials is too unwieldy because of their static nature. If you have this requirement, feel free to use the following parameters instead: "bucket", "bucket_region" (for example: "us-east-1" or "eu-west-2"), "key", "secret".

  • path — required

    string | Array<string>

    The path in your bucket to the specific file or directory. If the path points to a file, only this file will be imported. For example: images/avatar.jpg.

    If it points to a directory, indicated by a trailing slash (/), then all files that are direct descendants to this directory will be imported. For example: images/.

    Directories are not imported recursively. If you want to import files from subdirectories and sub-subdirectories, enable the recursive parameter.

    If you want to import all files from the root directory, please use / as the value here. In this case, make sure all your objects belong to a path. If you have objects in the root of your bucket that aren't prefixed with /, you'll receive an error: A client error (NoSuchKey) occurred when calling the GetObject operation: The specified key does not exist.

    You can also use an array of path strings here to import multiple paths in the same Robot's Step.

  • recursive

    boolean (default: false)

    Setting this to true will enable importing files from subdirectories and sub-subdirectories (etc.) of the given path.

    Please use the pagination parameters page_number and files_per_page wisely here.

  • page_number

    string | number

    The pagination page number. For now, in order to not break backwards compatibility in non-recursive imports, this only works when recursive is set to true.

    When doing big imports, make sure no files are added or removed from other scripts within your path, otherwise you might get weird results with the pagination.

  • files_per_page

    string | number

    The pagination page size. This only works when recursive is true for now, in order to not break backwards compatibility in non-recursive imports.

  • return_file_stubs

    boolean (default: false)

    If set to true, the Robot will not yet import the actual files but instead return an empty file stub that includes a URL from where the file can be imported by subsequent Robots. This is useful for cases where subsequent Steps need more control over the import process, such as with 🤖/video/ondemand. This parameter should only be set if all subsequent Steps use Robots that support file stubs.

  • range

    string | Array<string>

    Allows you to specify one or more byte ranges to import from the file. S3 must support range requests for this to work.

    Single range: Use a string like "0-99" to import bytes 0-99 (the first 100 bytes).

    Multiple ranges: Use an array like ["0-99", "200-299"] to import multiple separate ranges. The resulting file will contain all requested ranges concatenated together, with zero bytes (\0) filling any gaps between non-contiguous ranges.

    Range formats:

    • "0-99": Bytes 0 through 99 (inclusive)
    • "100-199": Bytes 100 through 199 (inclusive)
    • "-100": The last 100 bytes of the file

    Important notes:

    • S3 supports range requests by default
    • Overlapping ranges are allowed and will be included as requested
    • The resulting file size will be the highest byte position requested, with gaps filled with zero bytes
    • Each range is fetched in a separate request to ensure compatibility with S3

Demos

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