Docker NodeJS Language Translation Example

This repository is an introduction to Docker, which is a runtime for containers. We will create a containerized Node.js application that provides a service to translate phrases from one language to another. The application uses the Watson Language Translation service.

Running the application

You can use one of the following environments for this workshop

1. Install docker locally using Docker Desktop.
2. Use the web shell terminal provided to you via the IBM Cloud Shell.

Steps

Step 1 - sign up on IBM Cloud

Sign up for IBM Cloud here: https://cloud.ibm.com

Step 2 - activate your account

Click on the link in the email you received from IBM to activate your cloud account. Make sure you check the spam folder in your email.

Step 3 - create a language translation service

Log back into your IBM Cloud account using this URL: https://cloud.ibm.com

Click on Catalog

Search translator to find the service. You can also find the service by navigating to the AI section on the left bar.

Click on the service to create a new instance. Pick the Lite plan on the next page and click Create to finish creating the service.

You will be redirected to the service landing page.

Step 4 - copy the credentials to be used later

Click on Service Credentials on the left bar.

If you do not see a credential provided for you, you can create a new set of credentials. Save your apikey somewhere for the next section in this workshop.

Congratulations! You just signed up for IBM Cloud account and created your first Language Translator service. The next steps will show you how to build a Docker container for a Node.js application that provides an end point to translate text!

Step 5 - clone repository

Open your local terminal or the web terminal provided in the workshop and change to the /data directory. Close this directory.

cd data
git clone https://github.com/IBM/docker-nodejs-language-service.git

Step 6 - build the docker image

Change into the directory you just cloned and build the docker image.

cd nodejs-docker
docker build -t <docker-username>/node-container .

The docker-username is required if you want to publish your image to Dockerhub. If you do not have a Docker account - you would need to create one directly on hub.docker.com - choose sign up button. We also have the container published to ibmworkshop docker hub namespace, you would like to just pull ours down.

Alternatively, you can also build directly from github using the following command without cloning the repository:

docker build -t <docker-username>/node-container https://github.com/IBM/docker-nodejs-language-service.git

This command uses the Dockerfile to download a Node.js 10 base image and then install our Express.js application on top. Let's explore the contents of this docker file ...

FROM node:10

... builds our image on top of the Node.js 10 image.

WORKDIR /usr/src/app

... creates a working directory for our application to live in.

COPY package*.json ./

... copies the package.json file to our working directory.

RUN npm install

... install our dependencies. We just have two dependencies in this application: express and ibm-watson.

COPY . .

... copy the rest of our source code into the docker image

EXPOSE 8080

... expose port 8080. We will still have to forward our local port to this docker container port later.

CMD [ "node", "server.js" ]

... starts the application by running node server.js.

Step 7 - run the docker image

docker run -p 8080:8080 -e lt_key=<api_key> -e lt_url="<api_url>" -d <docker-username>/node-container

In my case, I would run

docker run -p 8080:8080 -e lt_key=tYCDgJhqWPn0f7zdUVRpzXhvgf64leLcWWNoxYmaIoSn -e lt_url="https://api.eu-gb.language-translator.watson.cloud.ibm.com/instances/743f0ce5-dae3-4442-a375-ba56d9c5f32e" -d ibmworkshop/node-container

Step 8 - test the application

curl "localhost:8080/translate?text=how%20are%20you"

You should see output as follows:

{
  "translations": [
    {
      "translation": "¿Cómo estás?"
    }
  ],
  "word_count": 3,
  "character_count": 11
}%

The text is translated to Spanish (en-sp) by default. You can specify the langauge by passing in the lang flag as follows:

curl "localhost:8080/translate?text=how%20are%20you?&lang=en-de"

You should now see the same text translated to German:

{
  "translations": [
    {
      "translation": "Wie geht es Ihnen?"
    }
  ],
  "word_count": 3,
  "character_count": 12
}

Another example ...

curl "localhost:8080/translate?text=People+are+suffering.+People+are+dying+and+dying+ecosystems+are+collapsing.+We+are+in+the+beginning+of+a+mass+extinction%2C+and+all+you+can+talk+about+is+the+money+and+fairy+tales+of+eternal+economic+growth"


{
  "translations": [
    {
      "translation": "La gente está sufriendo. La gente está muriendo y los ecosistemas moribundos se están derrumbando. Estamos en el principio de una extinción masiva, y todo lo que se puede hablar es el dinero y los cuentos de hadas del crecimiento económico eterno"
    }
  ],
  "word_count": 39,
  "character_count": 204
}

in Polish

curl "localhost:8080/translate?text=People+are+suffering.+People+are+dying+and+dying+ecosystems+are+collapsing.+We+are+in+the+beginning+of+a+mass+extinction%2C+and+all+you+can+talk+about+is+the+money+and+fairy+tales+of+eternal+economic+growth&lang=en-pl"
{
  "translations": [
    {
      "translation": "Ludzie cierpią. Ludzie umierają, a umierające ekosystemy się zapadają. Jesteśmy na początku masowego wyginięcia, a wszystko, o czym można rozmawiać, to pieniądze i bajki o wiecznym wzroście gospodarczym"
    }
  ],
  "word_count": 39,
  "character_count": 204
}

You can see the supported languages (both from and to) in the Language Translator documentation.

How cool was that! You just containerzied a Node.js application that provides transation services.

Clean up (this is optional)

Step 9 - stop the container

You can first stop the container. You need the container tag or the id to stop it. Let's look it up first

docker ps | grep node-container

419104eff9be        upkar/node-container                           "docker-entrypoint.s…"   3 minutes ago       Up 3 minutes                       0.0.0.0:8080->8080/tcp                            cranky_davinci

In my case, the container is called cranky_davinci and has an id of 419104eff9be.

Stop the image with the following command. You can replace the id with your container id.

docker container stop 419104eff9be

Step 10 - remove the container

Run the following command to remove the container. Replace the id with your container id identified in the step above.

docker container rm 419104eff9be

Step 11 - remove the image

You can now delete the image. You again need the image id.

$ docker images | grep node-container
ibmworkshop/node-container                       latest                         8baa6ca9cdac        5 minutes ago       958MB

Now, delete the image as follows.

$ docker image rm 8baa6ca9cdac
Untagged: ibmworkshop/node-container:latest
Deleted: sha256:8baa6ca9cdac8868d8e17642e90b433c7aa588a615b59ac9b528fb8635698a6e
Deleted: sha256:8c279f530b3ff260279f9cb8d22d167d748e53df4f6eab91b089b6c90b4da9f2
Deleted: sha256:9845fb86e05aa69c677dc999b6bbdeceafc460e70604092e0247e0f8880ec93e
Deleted: sha256:84ea0148452752e2aba0a1e1ef963355781a3fb87e485e9a440e8e8fc002d045
Deleted: sha256:f4f99031ae0d1cf0079d9981ef6e8dff2231eff670ac7ea4a4f27472282d7ad2
Deleted: sha256:bf579e37b35bb7b20ed0cb3140220118cbbd1d0564a512f21868568b3683a392
Deleted: sha256:07b958722eb2513e88186b2f6eddadcec0b8772001a598244352073ac5caf176
Deleted: sha256:361c46840912a7b9539b6ddf00164492fc594701085f0e2c9d2c1544bca8498c

Troubleshooting

Check container logs

You can check the logs for your container using

docker logs <container_id>

For example ...

root@terminal-5-846448d675-bk75j:/data# docker logs 4450279a9f50


Running on http://0.0.0.0:8080
No language passed to translate to. Converting to Spanish by default.
{
  "translations": [
    {
      "translation": "Hola"
    }
  ],
  "word_count": 1,
  "character_count": 5
}

Stretch goal

Congratulations again on creating your first docker container that hosts a Natural Language Translation service! Here is your next challenge if you choose to accept it!

Create a second image using the same Node.js 10 base image. Run a container based on this image. This container will host a tone analyzer service on port 8081. The service should expose an end point of /analyze, accept a parameter called text and give back the sentiment score on it.

Here are some hints to get you started ...

1. Create and change to a different directory /data/tone-container and clone the github repo https://github.com/IBM/docker-nodejs-language-service.git.
2. Create a Tone Analyzer service from IBM Cloud. You can search for tone analyzer in the catalog and pick the lite plan.
3. Copy the credentials somewhere safe. You will need the apikey in the next few steps.
4. Change the /translate endpoint to /analyze and write the code to return sentiments for the text in the request parameter. You can find the code in the API documentation for Tone Analyzer. If you are running out time, I have provided sample code here.
5. Build a new image and call it <docker-user>/tone-container.

cd /data/tone-container/nodejs-docker
docker build -t <docker-user>/tone-container .

6. Run a container based on the <docker-user>/tone-container image. Note that we are forwarding local 8081 to docker 8080. This is so that we don't create a conflict with the previous translator container.

docker run -p 8081:8080 -e "tone_key=<tone-analyzer-key>" -d <docker-user>/tone-container

Make sure to change the tone_key to your tone analyzer key.

You should now have two containers running in your terminal ...

NAMES                       IMAGE                                            STATUS
inspiring_nash              upkar/node-container                             Up 4 minutes
quizzical_thompson          upkar/tone-container                             Up 5 minutes

Test your new tone analyzer container as follows ...

Example 1

curl "localhost:8081/analyze?text=life%20is%20good"

Result

{
  "document_tone": {
    "tones": [
      {
        "score": 0.83112,
        "tone_id": "joy",
        "tone_name": "Joy"
      }
    ]
  }
}

Example 2

curl "localhost:8081/analyze?text=People+are+suffering.+People+are+dying+and+dying+ecosystems+are+collapsing.+We+are+in+the+beginning+of+a+mass+extinction%2C+and+all+you+can+talk+about+is+the+money+and+fairy+tales+of+eternal+economic+growth"

Result

{
  "document_tone": {
    "tones": [
      {
        "score": 0.819121,
        "tone_id": "sadness",
        "tone_name": "Sadness"
      },
      {
        "score": 0.686032,
        "tone_id": "confident",
        "tone_name": "Confident"
      }
    ]
  },
  "sentences_tone": [
    {
      "sentence_id": 0,
      "text": "People are suffering.",
      "tones": [
        {
          "score": 0.830428,
          "tone_id": "sadness",
          "tone_name": "Sadness"
        }
      ]
    },
    {
      "sentence_id": 1,
      "text": "People are dying and dying ecosystems are collapsing.",
      "tones": [
        {
          "score": 0.840601,
          "tone_id": "sadness",
          "tone_name": "Sadness"
        }
      ]
    },
    {
      "sentence_id": 2,
      "text": "We are in the beginning of a mass extinction, and all you can talk about is the money and fairy tales of eternal economic growth",
      "tones": []
    }
  ]
}

A complete step-by-step guide for running the application as a container can be found in our OpenShift 101 workshop.

License & Authors

If you would like to see the detailed LICENCE click here.

• Author: Developer Advocates, IBM

Copyright:: 2020- IBM, Inc

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.