Export files to Supabase Storage
🤖/supabase/store exports encoding results to Supabase Storage buckets.

Upload as a Supabase user
For Supabase session-token authentication, supply your project ref as key, your project’s anon key as secret, and the user’s access-token JWT as session_token. Supabase applies the authenticated user’s Row Level Security (RLS) policies to these uploads. Choose a path those policies permit, and use the endpoint and region from your project’s S3 connection settings.
Send the user’s JWT with each Assembly from your trusted backend. It must remain valid through queuing, processing, and upload retries; the Robot does not refresh it. Without session_token, continue using your generated Supabase S3 access key and secret. Those generated S3 access keys bypass RLS.
Supply session_token inline in the Step. Assembly Status returns fields unchanged, so passing the JWT through Assembly fields exposes it in the status response.
The result URL uses Supabase’s public-object URL format. It does not grant read access to a private bucket; use Supabase’s download authorization for private objects.
Usage example
Export uploaded files to my_target_folder in a Supabase Storage bucket:
{
"steps": {
"exported": {
"credentials": "YOUR_SUPABASE_CREDENTIALS",
"path": "my_target_folder/${unique_prefix}/${file.url_name}",
"robot": "/supabase/store",
"use": ":original"
}
}
}Parameters
interpolateboolean | Record<string, boolean>Controls whether Assembly Variables are interpolated for individual instruction fields.
By default, most Robot instruction fields interpolate Assembly Variables. Set this to
falseto treat every instruction field as literal text, or set an individual field path tofalseto treat only that field as literal text. For Robot-specific fields that are literal by default, set this totrueor set that field path totrueto opt back into interpolation.Use field names such as
path, or dotted paths such asffmpeg.vffor nested objects.output_metaRecord<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": truein this object to extract if the image contains transparent parts and"dominant_colors": trueto extract an array of hexadecimal color codes from the image.For images, you can also add
"blurhash": trueto 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 images,
"thumbhash": trueinstead extracts a base64-encoded ThumbHash intometa.thumbhash, together withmeta.has_alpha(whether an alpha channel exists, even when fully opaque). It describes EXIF-oriented pixels and uses the first frame of animated images. Extraction is best-effort: images above 40 megapixels, unsupported formats, or a failed/bounded decode produce no placeholder. Successful extraction adds a metadata charge equivalent to 20% of that file's bytes. No ThumbHash surcharge applies when disabled or when no hash is produced.Set this option on the Step producing the image, such as
/upload/handlefor uploaded originals or/image/resizefor processed outputs. Setting it only on/transloadit/storedoes not request extraction: storage preserves the producer's metadata. Transloadit Storage persists a generated hash with its immutable version and returns it in stored results and native asset reads. Direct S3 uploads do not generate placeholders. A placeholder contains image information, so protect it with the same access controls as the full image.For videos, you can add the
"colorspace": trueparameter to extract the colorspace of the output video.For videos, you can also add
"interlaced": trueto detect whether the video is interlaced. This combines the cheap ffprobefield_orderflag with a boundedidetsampling pass over the first frames of the source, exposinginterlaced,field_order, and a diagnosticinterlace_detectionobject underfile.meta. This is computationally expensive and billed accordingly.For audio, you can add
"mean_volume": trueto get a single value representing the mean average volume of the audio file.You can also set this to
falseto skip metadata extraction and speed up transcoding.user_metaRecord<string, any>(default:{})Adds custom JSON metadata to each emitted file without changing its contents. Nested objects and arrays are supported.
Inheritance depends on the Robot. Values merge with existing
user_metaon the output file; the current Step replaces matching top-level keys. Assign required keys explicitly when a Robot creates fresh outputs.In processing Steps,
${file.*}refers to the first input and${result.*}to the emitted file. Values are evaluated per output after the Robot runs, before subsequent metadata extraction and temporary storage. On:original, values are evaluated per upload before metadata extraction.Downstream Steps read
${file.user_meta.key}. See Custom metadata for a complete example and inheritance rules.resultboolean(default:false)Whether the results of this Step should be present in the Assembly Status JSON
queuebatchSetting 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_acceptboolean(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_acceptparameter set totrue, 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.ignore_errorsboolean | Array<meta | execute>(default:[])Ignore errors during specific phases of processing.
Setting this to
["meta"]will cause the Robot to ignore errors during metadata extraction.Setting this to
["execute"]will cause the Robot to ignore errors during the main execution phase.Setting this to
trueis equivalent to["meta", "execute"]and will ignore errors in both phases.usestring | Array<string> | Array<object> | objectSpecifies which Step(s) to use as input.
- You can pick any names for Steps except
":original"(reserved for user uploads handled by Transloadit) - You can provide several Steps as input with arrays:
{ "use": [ ":original", "encoded", "resized" ] } - You can also tag input Steps with
asto pass semantic intent to robots:{ "use": [ { "name": ":original", "as": "image" }, { "name": ":original", "as": "mask" } ] }
TipThat's likely all you need to know about
use, but you can view Advanced use cases.- You can pick any names for Steps except
credentialsstringThe name of your Supabase Template Credentials, containing the bucket, host, key, secret, and bucket region. You can instead supply those parameters directly in the Step.
For generated S3 access-key authentication, use the endpoint and S3 access keys from your Supabase project’s S3 connection settings. For user-scoped session-token authentication, use the project ref as
keyand the project’s anon key assecret, then supply the user’s access-token JWT assession_tokenwith each Assembly.bucket_regionstringThe region where the bucket is located.
pathstring(default:"${unique_prefix}/${file.url_name}")The path at which the file is to be stored. This may include any available Assembly variables. The path must not be a directory.
session_tokenstringThe user’s Supabase access-token JWT for session-token authentication. Use the Supabase project ref as
keyand the project’s anon key assecretso Supabase applies that user’s RLS policies. The JWT must remain valid through queuing, processing, and upload retries; the Robot does not refresh it. Supply this value directly in the Step; Assembly Status exposes values infields.headersRecord<string, string>(default:{"Content-Type":"${file.mime}"})An object containing a list of headers to be set for this file in your Supabase Storage bucket, such as
{ FileURL: "${file.url_name}" }. This can also include any available Assembly Variables.Object Metadata can be specified using
x-amz-meta-*headers. Note that these headers do not support non-ASCII metadata values.