Glossary
To build all of Transloadit we didn't just invent a few Robots, we also invented some vocabulary to go with it. For reference, here is all of Transloadit's Terminology in one place.
Assembly
An Assembly is the execution of file conversion instructions (called Assembly Instructions) on uploaded and/or imported files. Each Assembly has a unique assembly_id identifier that can be used to refer to the Assembly in subsequent API requests.
Assembly Execution Progress
Assembly Execution Progress provides real-time estimates on the progress of an Assembly's execution. The percentage value is estimated based off the Steps in the Assembly, for both the progress of the Assembly as a whole, as well as for the progress of each individual file.
Assembly Instructions
Encoding or Assembly Instructions consist of all the Assembly Steps that are executed on the uploaded/imported files by the Transloadit back-end.
Assembly Notification
You can be notified when an Assembly has finished executing by having the Assembly Status sent in a POST request to a URL of your choice. Using Assembly Notifications is entirely optional.
Assembly Replay
Assemblies are executed on a large pool of servers and sometimes it happens that a server malfunctions. If your Assembly Instructions were saved in a Template, and as long as the uploads (if any) completed successfully, Transloadit is able to replay Assemblies within 24 hours. We will attempt to do so automatically in cases where the Assembly Status is ASSEMBLY_CRASHED (which means that a server malfunctioned), but it can also be triggered manually in the account section of our website.
Assembly Status
When an Assembly has been created, an Assembly Status URL is returned. At this URL endpoint, you can find all kinds of useful information about the Assembly in JSON format. This includes the Assembly's id, its uploads, its results (appended as they are processed), its execution duration, and much more. You can fetch the URLs to your result files from the Assembly Status and then display them, or save them in your database.
Assembly Step
A single file conversion Step that files undergo during an Assembly. Each Step performs some type of encoding, resizing or conversion. You are free to name Steps however you like in the Assembly Instructions.
Assembly Variable
Assembly Variables are special placeholders such as ${file.original_basename} that can be used in any Robot to dynamically influence its encoding behavior based on the currently converted file or the values of hidden fields in the submitted HTML form.
Async Mode
In Sync Mode, the client that issues the request transmits files, waits for encoding, and then gets the results for further processing. This is different from Async Mode, where the client can be on their way as soon as the request and/or upload completes, and Transloadit will notify your back-end of the results via an Assembly Notification.
Auth Key
The Auth Key can be regarded as your Transloadit username for use in automation. Your Auth Key is not secret and can be used to publicly identify your account.
Auth Secret
The Auth Secret can be regarded as your Transloadit password for use in automation. Only you and Transloadit should know your Auth Secret. If you suspect your Auth Secret has been compromised, you are advised to generate a new one, which automatically invalidates the old one.
Batch Queue
Slower processing can happen when Encoding Jobs are downgraded to the Batch Queue. This happens on customer request, for Jobs that are the result of an Import Robot, or when there is a large volume of Jobs by a single IP or Customer. This way, heavy batch processing is never blocking avatar resizes that need to feel instant, and are handled in the Live Queue.
Collaboration Seats
Collaboration Seats allow multiple users under different emails to easily collaborate on the same App Templates and Assemblies without needing to log into the main account.
Encoding Job
The smallest processing unit in the Transloadit vocabulary, such as a single video encoding, or an image resize, to be executed on our encoding machines.
Job Slot Limit
The configurable per-customer-value that determines when Encoding Jobs trickle down from the Live Queue into Batch Queue.
Live Queue
This is Transloadit's fast lane. The capacity for this can't be scaled up and needs to be on standby. This makes it more expensive for Transloadit to operate, so we handle a limited (but configurable) amount of Jobs for customers in near-realtime. This is makes sure avatar resizes are not blocked by truck-loads of video encodes (handled in the slower Batch Queue).
Priority Job Slot
An Encoding Job can take up to 8 Job Slots depending on the estimated required machine capacity. Jobs Slots occupied by a single customer or IP are summed up to determine when Encoding Jobs trickle down from the Live Queue into Batch Queue.
REST API
Our REST API provides programmatic access allowing Transloadit to start encoding jobs for you. It is available over plain HTTP(S), which means you can integrate with us using any platform or language that is able to communicate with it. We do, however, recommend using one of our SDKs. These provide boilerplate for common operations and will save you valuable coding time.
Rate Limiter
To protect customers from other customers' mistakes, we limit the number of Assemblies that can be created to 250 per minute, up to a default maximum of 250 concurrent Assemblies. If your use-case warrants a higher limit, we can adjust this for you upon request.
Robot
Transloadit offers many features for processing files, that we have condensed in Robots. One Robot can do one thing really well, such as: image resizing. When you integrate with Transloadit, you can combine many Robots and put them to work in an Assembly, one Robot handing its results to the next. This allows to create unimagined workflows and encoding pipelines, unique to your use case.
Robot Parameter
Those parameters of a Step that influence a Robot's behavior, such as width for an image resize, instead of parameters in a Step that influence the Assembly flow such as use.
Signature Authentication
With Signature Authentication, you use an Auth Secret that is known only by you and Transloadit to encrypt instructions and an expiration date. When the Assembly Instructions arrive at Transloadit, we will also encrypt them along with the expiration date, in order to verify whether the resulting signature matches the one you provided. Enabling Signature Authentication ensures that Assembly Instructions cannot be tampered with by anybody who does not know your Auth Secret. People will also not be able to submit Assemblies on your behalf, driving up your invoices.
Signature Authentication for Notification
With Signature Authentication for Notifications, you use an Auth Secret that is known only by you and Transloadit, which Transloadit then uses to encrypt results, instructions and an expiration date. When the Notification arrives at your backend, you will also encrypt it along with the expiration date, in order to verify whether the resulting signature matches the one we provided. With Signature Authentication for Notifications you can be sure that it was Transloadit who sent you the Notification, and that it hasn't been tampered with by anybody who does not know your Auth Secret.
Sync Mode
In Sync Mode, the client that issues the request transmits files, waits for encoding, and then gets the results for further processing. This is different from Async Mode, where the client can be on their way as soon as the request and/or upload completes, and Transloadit will notify your back-end of the results via an Assembly Notification.
Template
A Template allows you to save Assembly Instructions securely in your account on transloadit.com. That way, you can hide these instructions from your users. You would then reference them via a template_id parameter in your API request, making your requests lightweight and secure.
Template Credentials
Template Credentials allow you to save access credentials for your storage providers like Amazon S3, Google Storage or Rackspace Cloud Files securely in your account on transloadit.com. They allow you to re-use the same storage credentials across many Templates without having to duplicate them in each Template.
Template Editor
The UI in your account section on our website that allows you to add and edit Templates. It has a code editor that is aware of our declarative JSON language and can assist you in creating powerful workflows.