GORT

GORT is a simple HTTP handler to receive remote calls to run scripts bundled in Docker containers. Why the name is gort - because the idea is "GO-Run-Things"

Safety notice: Until this tool doesn't have the authorization, you need to cover it using any firewalls or use it as internal service in your k8s cluster without exposing it outside.

Usage

Refer to Install for getting gort binary

To use gort in your Docker container download the latest version from Project Release Page

$ ./gort
2019/10/30 12:32:06 Gort is started on port 5000

GORT uses the following environment variables for a customized run

PORT as default will be handled over 5000 port

SCRIPTS_DIR by default will search scripts at ./dist in the same directory where the binary

GORT_RATE_LIMIT is a parameter to set Throttle Limit, Throttle is not a rate-limiter per user. Instead, it just puts a ceiling on the number of current in-flight requests

Endpoints

Health

Allows you to check the health of application/container

• URL

  /v1/health

• Method

  GET

• Success Response

  • Code: 200
    Content: OK

List

List scripts directory

• URL

  /v1/list-dist

• Method

  GET

• Success Response

  • Code: 200

Start

Allows you to start script from the scripts directory

• URL

  /v1/start

• Method

  POST

• Data

  Requires JSON data as payload

  {
    "executor": "node",
    "script": "script.js",
    "env_vars": [
      "FOO=bar",
      "BAR=foo"
    ],
    "args": [
      "--foo=bar",
      "--bar=foo"
    ]
  }

• Success Response

  • Code: 200
    Content: The function is executed in the background. Refer to container logs to see the output

• Error Responses

  • Code: 400
    Content: Required parameters 'executor' and 'script' were not found in the payload

  • Code: 422
    Content: Not able to parse data as valid JSON

  • Code: 500
    Content: Requested executor is not installed

  • Code: 501
    Content: Requested script is not found in the scripts directory

• Sample Call:

$ curl -X POST http://127.0.0.1:5000/v1/start -d '{"executor":"python", "script": "crawler.py"}'
The function will be executed in the background. Refer to container logs to see the output

Install

Binary

Binary are available for download on the Project Release Page

However, you also able to change something in the source code and build your Gort for yourself

$ go build ./...

Use cases

Dockerfile Example Usage

For instance, we have a few crawlers which should be executed on demand.

They was built by NPM

#
# STEP ONE: Build scripts
#
FROM node:10 AS builder
# Create app directory
WORKDIR /app
# Copy our files inside of the docker builder
COPY . .
# Install dependencies
RUN npm install && npm build
#
# STEP TWO: Build our images bundled with gort and copy scripts from builder
#
FROM alpine
# Create app directory
WORKDIR /app
# Install dependecies
RUN apk add --no-cache bash nodejs ca-certificates && \
    wget https://github.com/idestis/gort/releases/download/1.0.0/gort_1.0.0_linux_amd64 -O gort && \
    chmod +x gort
# Copy our scripts from builder step
COPY --from=builder /app/dist /app/dist
# PORT variable for Gort
ENV PORT 8080
# Expose outside
EXPOSE 8080
ENTRYPOINT ['gort']

After when we published and executed this docker container elsewhere, we can send requests to start any our function

$ curl -X POST https://address/v1/start -d '{"executor":"python", "script": "example.py"}'
The function will be executed in the background. Refer to container logs to see the output

In STDOUT of the container we will be able to see logs

2019/10/30 12:19:01 Just ran subprocess of example.py with PID 52177

For instance, you can schedule this runs using your services or any CI tool like Jenkins, drone.io

Contribute

Refer to CONTRIBUTING.md

Dependencies

• github.com/go-chi/chi

TBD

• Authorization method to protect your endpoints
• Subprocesses list
• Cleanup zombie subprocesses