npm i @scramjet/reference-inert-3-seq


Flexible and efficient data processing engine and an evolution of the popular Scramjet Framework based on node.js. Our Transform Hub was designed specifically for data processing and has its own unique algorithms included.

by scramjetorg

0.22.0 (see all)License:ISCTypeScript:Not Found
npm i @scramjet/reference-inert-3-seq

Scramjet Transform Hub

GitHub license STH version GitHub stars npm Discord Donate

⭐ Star us on GitHub — it motivates us a lot! 🚀

Scramjet Transform Hub Logo

The Idea

Scramjet Transform Hub is a serverless system that allows you to easily deploy, run and interconnect programs that process repetitive data tasks in long-running processes. STH can be run just as well on a Raspberry Pi as it can on a massive 128 core Epyc bare metal server. It installs in one simple command and deploys your app to the cloud just as easily... Oh, and the app is incredibly simple too:

export (input: Readable) => async function*() {
     for (const post of input) {
         if (!cache.has(post.id)) {
             yield await slack.note(`New post titled "${post.title}" from ${post.author}`);

It currently supports Node.js based apps, but Python and other languages are coming.

Get Scramjet Transform Hub straight from NPM

Table of contents

Introduction 🤝

This is a development repo for Scramjet Transform Hub, a container supervisor that allows deployment, execution and monitoring of any application based on a simple interface.

This repository contains the source code for https://hub.scramjet.org.

If you want to read the usage docs, go here ☝🏼

What's more, this repository is intended for developers who would like to:

  • participate in the Scramjet Transform Hub development community
  • register feature requests, issues and PRs for this product
  • build Transform Hub from source
  • dive into code and see how it works

The developers who would like to simply use Scramjet Transform Hub to run data processing applications, we recommend following resources:

gh_logo Repository with Introductory README and code samples

npm_logo NPM page for main scramjet/sth package

npm_logo NPM page for scramjet/cli package

Usage 💡

Scramjet Transform Hub is a deployment and execution platform. Once installed on a server, it will allow you to start your programs and keep them running on a remote machine. You will be able to start programs in the background or connect to them and see their output directly on your terminal. You will be able to pipe your local data to the program as if it was running from your terminal. You can start your server in AWS, Google Cloud or Azure, start it on your local machine, install it on a Raspberry Pi or wherever else you'd like.

There's no limit to what you can use it for. Do you want a stock checker? A chatbot? Maybe you'd like to automate your home? Retrieve sensor data? Maybe you have a lot of data and want to transfer and wrangle it? You have a database of cities and you'd like to enrich your data? You do machine learning and you want to train your set while the data is fetched in real-time? Hey, you want to use it for something else and ask us if that's a good use? Ask us via email 📧 or hop on our Scramjet Discord discord

Check our proposition of sample architecture for use cases in different industries.

This is the STH development repo, in order to use it, you need to have linux based operating system, for instance Ubuntu installed. We also use docker and node.js v16.x. We're working on development guides for Mac and Windows. 🔜

The basics 🔡

Scramjet Transform Hub allows you to deploy and execute programs that you build and develop. As mentioned above, you can run any program you like, but you need to know a couple of important things:

  • The program should consist of a function or an array of functions, such a program is called a Transform Sequence.
  • The Sequence will be executed within a separate docker instance (🔜 we're working on other execution environment integrations - help will be appreciated 🦾).
  • The Sequence function will receive a stream as input in the first argument - you can send the data to it via the command si instance input.
  • If your Sequence contains more than one function, then the output from the first function is passed to the next one. Also, the first function in Sequence receives the input from API.
  • The last (or the only) function in Sequence can return a Promise or a Stream - based on this, STH will know when processing is done.
  • Once the returned Promise is resolved, or the Stream is ended, STH will gracefully stop the Sequence and remove its container.
  • You can communicate with the server via API, command line client si which we wrote for your convenience.
  • The Sequence is called with an AppContext as this, a class that allows you to communicate back from the Sequence: send logs, provide health info, send and receive events from the API or CLI.
  • You can run your Sequence multiple times with different arguments (like for instance currency tickers with different symbols or sensor data readers for each sensor)
  • The program does not leave your server and doesn't use any external systems. It runs on the server you install the host on.
  • Currently STH supports node.js runner only, we're working on bringing you runners for other languages, with Python and C++ as the first ones.

Some important links 👀:

Development instructions 👷‍♂️

This section contains more detailed installation descriptions, it is intended for developers who would like to contribute or build Transform Hub from source. If you wish to fire up STH quickly and without unnecessary installations, go to Quick Start installation, which focuses on starting STH and deploying a sample application.

In this section we will also show you some useful commands, tools and functionalities that you can use to develop your own programs.

If you want to help out, we're happy to accept your pull requests. Please follow the below information to start development.

Installation :clamp:

Reminder: This is a development guide. In order to use it, you need to have linux based os (e.g. Ubuntu), docker and node.js v16.x installed. We're working on development guides for Mac and Windows. 🔜

Environment setup

Our hub is based on node.js, so you need to install node.js and npm, which is the default package manager for node.js. We will guide you step by step through the installation process.

There are several installations you need to perform to get STH up and running, and even more to start developing with us. You may already have some of these below installed, but we will show you how to install them anyway.

  • nvm
  • node.js
  • lerna
  • yarn
  • typescript
  • ts-node
  • docker
  • pip

To check if you already have Node.js(v16.xx.x) and npm installed, please check the installed version, run the following commands in your console:

node -v
npm -v

If none of the above commands is found, please proceed with the installation.

It is recommended to use a Node version manager like nvm to install Node.js and npm. Do it by running the install script using the following cURL command presented below in your console. Make sure you replace v0.39.0 with the latest version of nvm. The actual version of nvm to install is here.

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.0/install.sh | bash

After executing the above command you should get in the console this info:


Which means that you need to run those two more commands to finish the installation:

export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion"

Export lines from above will be saved in your ~/.bashrc file so that you will not need to run it every session start. After that you can check nvm version just to confirm that you have successfully installed nvm.

command: nvm --version

output e.g.: v0.37.2


Now you are ready to install node.js, simply type in your console:

nvm install 16     # command will install latest LTS Version of Node.js

💡 Note: The project is working on Node Long Term Support (LTS) Version, which contains Node Package Manager (NPM) in ^8.1.0 version. NodeJS in version ^17.XX.X will install NPM in version ^8.1.2 and we don't use it right now 😉.

🤓 For more info you can check out the node.js official webpage.

Now you can check the installed version of node.js and npm, run the following command in your console:

command: node -v

output: v16.13.0

command: npm -v

output: 8.1.0


OK! It looks like you have successfully installed node.js and npm. There are two more installations you need to perform, run the following commands in your console one after another:

npm install -g lerna
npm install -g yarn


The same as before the installations can be confirmed by checking the installed versions:


OK! The installation was successful. 🎉 🎆

STH can run python packages, and for that it needs to have python and pip. These should be already installed on your system - check with:

python --version
pip --version

If they are not present, refer to the official installation guide for Python and Pip.

We also work with Docker, but this is optional. Running STH is possible without Docker in the background. If you don't want to use Docker, please skip this step. If you want to use Docker, you can install it by running the following commands in your console:

sudo apt install -y docker.io docker-compose   # command will install docker and docker-compose
sudo gpasswd -a $USER docker   # command will add you to the docker group

Verify that Docker and Docker-Compose are installed by getting their versions:

sudo docker version
docker-compose version

STH installation

There are two ways to install STH, either by cloning the repo or by using the npm registry.

First, let's clone the transform-hub repo. After that, some more installations will be required. Please copy the following commands to the terminal:

git clone https://github.com/scramjetorg/transform-hub.git && \
cd transform-hub && \
yarn install && yarn build:all && npm i -g ./dist/cli

Depending on your machine this may take some time, so it is a perfect time for another hot beverage ☕ or walk 🚶🏼‍♀️ or joggling 🤹‍♂️ or push-ups maybe..? no? Then simply wait 🧘 Meantime let me describe you what is happening in the command you have just pasted into the console:

  • git clone https://github.com/scramjetorg/transform-hub.git is cloning STH repository.
  • cd transform-hub is changing the directory to STH repository.
  • yarn install is installing all the dependencies of STH.
  • yarn build:all is building all STH packages, this script includes three other building scripts (yarn build:packages && yarn build:refapps && yarn build:docker).
  • npm i -g ./dist/cli is installing STH CLI as a global command.

When the package installation and build is complete, STH should be ready to run. To confirm that we will try to start it. There are several ways to do it, but for now we will use the script that will run STH from node:

yarn start -P 8000

The parameter -P makes STH listen on port 8000. If you skip this parameter, it will listen on port 8000 anyway. This port is set as a default value in STH configuration file.

When it's done, STH should be running and you should see initial logs showing that the API server has been started on port 8000, something like this:

2022-01-14T10:26:39.201Z info (object:Host) API listening on:

STH is all set and ready to work with. To stop it use Ctrl+C or kill the process with command: kill -9 $(lsof -t -i:8000).


As we mentioned before, the current STH can be also installed from the npm registry -> @scramjet/sth:

npm i -g @scramjet/sth   # installs the package globally


When you start STH from npm, no package installations or builds are required. You can start STH right away, with one of those two commands: scramjet-transform-hub or sth.

If you managed to start STH, it confirms that the installation process was performed successfully. This is the command we used to start STH: yarn start -P 8000. The -P option is used to start STH on localhost and port number 8000 ( It is worth mentioning, that STH can be started on any port number, and it can be started in several ways, which is described in the following section.

Start STH 🏁

STH can be started in multiple ways. The default way is to run it with Docker and on localhost and port number 8000.

node dist/sth/bin/hub                 # Starts Host after it's been built

yarn start                            # This is the same as above but using script

ts-node packages/sth/src/bin/hub.ts   # Starts Host in development mode

yarn start:dev                        # This is the same as above but using script

You can also start STH without Docker, use the same commands as above but with added --runtime-adapter=process option:

node dist/sth/bin/hub --runtime-adapter=process

yarn start --runtime-adapter=process

ts-node packages/sth/src/bin/hub.ts --runtime-adapter=process

yarn start:dev --runtime-adapter=process

There is a wide range of options that you can start STH with. Please add --help or -h flag to list all the options:

scramjet-transform-hub --help


sth --help

$ sth --help
Usage: sth [options]

  -L, --log-level <level>         Specify log level (default: "debug")
  -S, --socket-path <socket>      CSI socket location
  -P, --port <port>               API port
  -H, --hostname <IP>             API IP
  -E, --identify-existing         Index existing volumes as sequences (default: false)
  -C, --cpm-url <host:ip>
  --id <id>
  --runner-image <image name>     Image used by runner
  --runner-max-mem <mb>           Maximum mem used by runner
  --prerunner-image <image name>  Image used by prerunner
  --prerunner-max-mem <mb>        Maximum mem used by prerunner
  --expose-host-ip <ip>           Host IP address that the Runner containers port is mapped to.
  --runtime-adapter <type>        Run all the instances on the given type of container or on host machine. Possible value: `process`, `docker`, `kubernetes`. Keep in mind that using `process` is UNSAFE FOR RUNNING ARBITRARY CODE.
  --sequences-root                Only works with --runtime-adapter=process option. Where should ProcessSequenceAdapter save new sequences
  -h, --help                      display help for command

Install CLI and execute ✅

Thi installation was already done at the end of the Installation section, just before starting STH. But it is worth mentioning, that there are two ways to install the CLI:

  • from the source code. In the root folder, after building, run the commands:
npm i -g ./dist/cli # install CLI globally from the source folder
si help             # show CLI commands
npm i -g @scramjet/cli # install CLI globally from npm
si help                # show CLI commands


Running si help command will confirm that the installation went properly and also to see the list of available commands:


We will use CLI later on to execute the Sequence. You can also jump right away to CLI reference.

Build the packages 🏗️

All the packages in the project need to be installed and built before the can be used.

Install will create a node_modules folder in the root of the project and in each package (dependencies will be installed).

Build will create a dist folder in the root of the project and in each package. The folder will contain the files with the code compiled into JavaScript.

This is how to perform a clean install and build of all the packages:

yarn install:clean        # this command will perform 'yarn clean && yarn clean:modules && yarn install' at once
yarn build:all-packages   # optionally 'build:all' if you want all dockerfiles.


💡 HINT: For more scripts please see "scripts: {}" in main package.json.

Docker commands 🐳

During development, some artifacts may be leftover in docker. See how to clean them:

docker ps                      # list containers
docker volume prune -f         # remove all unused local volumes
docker system prune --all -f   # remove all unused images not just dangling ones
docker stop $(docker ps -a -q) # stops all running containers

*(-f) - doesn't prompt confirmation

Build Hub on Docker 🏗️

Build from current source:

cd ./packages/host/
yarn build:docker

Build current release:

cd ./packages/host/
yarn build:docker-release

Run Transform Hub in Docker :robot:

cd ./packages/sth/
docker-compose up

# or run in detached mode
docker-compose up -d
docker-compose logs -f

To run Hub without docker-compose:

docker run \
  -ti  \
  --name scramjet-hub \
  --init \
  -p 8000:8000 \
  -v /tmp/:/tmp/ \
  -v /var/run/docker.sock:/var/run/docker.sock \
  scramjetorg/sth:$(jq -r .version package.json)

Lerna commands 📝

We use Lerna to control our monorepo. Here's a couple of helpful commands, which might be useful during development:

lerna create package_name # Add new package:
lerna ls                  # List all of the public packages in the current Lerna repo:
lerna run [script]        # Run an npm script in each package that contains that script.
lerna run --ignore @scramjet/<package_name> <script-name>
    # Run script in all packages excluding one package:
lerna run --ignore @scramjet/<package_name> --ignore @scramjet/<package_name> <script-name>
    # ... or run script excluding more packages
lerna run --scope @scramjet/<package_name> <script-name>
    # Run script only in one package
lerna run --scope @scramjet/<package_name> --scope @scramjet/<package_name> <script-name>
    # Run script in more packages

Autocomplete ⚡

Completion script depends on bash-completion so make sure it's already installed by running type _init_completion.

Below command installs completion script in ~/.bashrc.

si completion install

For immediate effect make sure to run source ~/.bashrc. Also you can manage completion script by yourself. Running si completion bash prints script to the terminal.

Sample usage 😎

"Hello Alice" sample 👋

The sample will work only if you have properly configured your environment, installed hub and build all the packages. By this time you should already have all those things done by going through the Installation section.

💡 HINT: The following instructions apply to the state of the repository from the release/0.14.

To start the "Hello Alice" sample we will need these basic steps:

Compress the Sequence

The Sequence needs to be compressed into a tar.gz file format before we send it to the hub.

Assuming that you have the host running use the command:

yarn build:refapps    # this builds all the refapps in the 'reference-apps' package

When the host is not running you can use a script:

lerna run prepare-sample-tar

To compress specific package use linux tar command:

tar -C /path/to/package/dir czf <package-name.tar.gz> .

Execute sample

To execute the sample run the commands listed below from the level of the main folder.

💡 HINT: remember that to use curl commands hub must be running. See how to start STH =>

Upload the package

Copy and paste the following command to the terminal:

SEQ_ID=$( \
    curl --location --request POST "http://localhost:8000/api/v1/sequence" \
    --header 'content-type: application/octet-stream' \
    --data-binary '@packages/reference-apps/hello-alice-out.tar.gz' | jq ".id" -r \

During your development or checking out our code, you may want to edit some of our reference apps. After that you are very welcome to use our scripts to speed up your developing process. In this case, you can use the following, that will build and send any of the reference packages and samples in this repo:

SEQ_ID=$(./scripts/_/upload-sequence packages/reference-apps/hello-alice-out) # -> when you want to upload the package (it will be built if needed)
SEQ_ID=$(./scripts/_/upload-sequence packages/reference-apps/hello-alice-out -r) # -> when you want to upload the package and make sure it's rebuilt
SEQ_ID=$(./scripts/_/upload-sequence dist/my-package.tgz -r) # -> when you want to upload a ready tarball

Start the Sequence

Copy and paste the following command to the terminal:

INSTANCE_ID=$(curl --location --request POST "http://localhost:8000/api/v1/sequence/$SEQ_ID/start" \
--header 'content-type: application/json' \
--data-raw '{
    "appConfig": {},
    "args": ["/package/data.json"]
}' | jq ".id" -r)

💡 HINT: INSTANCE_ID and SEQ_ID are shell variables.

GET the output

To get the output we need to send GET request to /stdout endpoint:

curl --location --request GET "http://localhost:8000/api/v1/instance/$INSTANCE_ID/stdout" \
--header 'Transfer-Encoding: chunked' \
--header 'content-type: application/octet-stream'

This is what you should get as a result:


See more about streams and curl commands =>

More samples 📚

To check out more of our ready-to-go samples, please go to our Quick Start repo on GitHub, samples directory.

Configure your own sample 📝

We have also prepared a template for you to use. You can use it as a base for your own samples 👉 sample template. For this moment we support two variants of template in two programming languages:

There are two more templates that we will support, but they are still in development stage:

  • Python
  • C++

Troubleshooting 💥

Docker issues:

Error: connect ENOENT /var/run/docker.sock

During sending the Sequence compressed package to the host you may come across this error:

  • Error: connect ENOENT /var/run/docker.sock

    2022-01-13T11:54:26.948Z info (object:Host) New sequence incoming...
    2022-01-13T11:54:26.948Z log (object:DockerSequenceAdapter) DockerSequenceAdapter init.
    2022-01-13T11:54:26.948Z log (object:DockerodeDockerHelper) Checking image scramjetorg/pre-runner:0.14.0
    2022-01-13T11:54:26.949Z log (object:DockerodeDockerHelper) Start pulling image scramjetorg/pre-runner:0.14.0
    2022-01-13T11:54:26.949Z debug (object:Host) Error: connect ENOENT /var/run/docker.sock
        at PipeConnectWrap.afterConnect [as oncomplete] (node:net:1161:16)
    2022-01-13T11:54:26.950Z debug (object:Host) Request date: 2022-01-13T11:54:26.948Z, method: POST, url: /api/v1/sequence, status: 422

To solve this issue you need to install docker and docker-compose. You can install them using the following command below or refer to official Docker instructions.

sudo apt install -y docker.io docker-compose
Error: connect EACCES /var/run/docker.sock

During sending the Sequence compressed package to the host you may come across this error:

  • Error: connect EACCES /var/run/docker.sock

    2022-01-13T11:58:00.368Z info (object:Host) New sequence incoming...
    2022-01-13T11:58:00.369Z log (object:DockerSequenceAdapter) DockerSequenceAdapter init.
    2022-01-13T11:58:00.370Z log (object:DockerodeDockerHelper) Checking image scramjetorg/pre-runner:0.14.0
    2022-01-13T11:58:00.375Z log (object:DockerodeDockerHelper) Start pulling image scramjetorg/pre-runner:0.14.0
    2022-01-13T11:58:00.377Z debug (object:Host) Error: connect EACCES /var/run/docker.sock
        at PipeConnectWrap.afterConnect [as oncomplete] (node:net:1161:16)
    2022-01-13T11:58:00.379Z debug (object:Host) Request date: 2022-01-13T11:58:00.373Z, method: POST, url: /api/v1/sequence, status: 422

To solve this issue you need to add the current user to the docker group, please use this command:

sudo gpasswd -a $USER docker

Packages issues:

Errors related to build packages

If something goes wrong during building packages, any errors occur, please try to run clean build, which will remove all node_modules and dist directories, after that you try to install and build them again.

yarn clean && yarn clean:modules && yarn install && yarn build:all
Errors related to reference-apps package

Every reference-app package before we run it, needs to:

  • have node_modules installed (yarn install)
  • have dist directory created and tar.gz package created (yarn build:refapps)

Remember to install dependencies and build your sample package before compressing it.

If you create your sample in packages/reference-apps folder, you can use the following command to build it:

yarn build:refapps

It will build all the packages in the packages/reference-apps folder.

💡 HINT: Have a look at the root package.json, there is the scripts section, which contains the list of all the scripts you can run with lerna. You may find them useful.

Log an issue/bug every time you encounter a problem or find a bug. Maybe you will also find that some feature is missing?

Cloud Platform Beta is coming 🥳

Beta program

License and contributions 📃

This project is dual licensed under the AGPL-3.0 and MIT licenses. Parts of the project that are linked with your programs are MIT licensed, the rest is AGPL.

We accept valid contributions and we will be publishing a more specific project road map so contributors can propose features and also help us implement them. We kindly ask you that contributed commits are Signed-Off git commit --sign-off.

We provide support for contributions via test cases. If you expect a certain type of workflow to be officially supported, please specify and implement a test case in Gherkin format in bdd directory.

More info about bdd tests can be found here.

Help wanted 💁‍♀️

The project need's your help! There's lots of work to do and we have a lot of plans. If you want to help and be part of the Scramjet team, please reach out to us, on discord or email us: opensource@scramjet.org.

Donation 💸

Do you like this project? It helped you to reduce time spent on delivering your solution? You are welcome to buy us a coffee ☕




GitHub Stars



2mos ago








18d ago
No alternatives found
No tutorials found
Add a tutorial