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Version: v2 ⚡

CLI Challenges

Solve real-world problems and showcase your command-line skills by participating in our CLI challenges​

Important Notes

  • A developer with a bit of Javascript experience should be able to write, run, and debug complex, multi-step jobs with OpenFn, using nothing but a text editor and their terminal.

  • If you are stuck and need help, please post in community.openfn.org.

    Expand to see bug report template
    Subject: Bug Report - [Brief Description]

    **Description:** [Concise description of the bug.]

    **Steps to Reproduce:**

    1.
    2.
    3.

    **Environment:**

    - OS: [e.g., Windows 10]
    - CLI: [e.g., v0.4.11]
    - Node: [e.g., v 18.17.1]
    - NPM: [e.g., 8.19.2]

    **Attachments:** [Screenshots, error messages, or relevant files.]

🏆 Create personalized greeting​

Overview:

Create a new hello.js job to display a personalized greeting with your name.

Objective:

Compose a OpenFn job using common adaptor that outputs a greeting message containing your name.

Requirements:

  1. Install the latest version of common adaptor.

    openfn repo install @openfn/language-common

Tasks:

  1. Create a new file named hello.js.
  2. Write a JavaScript script in hello.js to generate a greeting with your name.
  3. Run the job using the command openfn hello.js -a common -o tmp/output.json.
  4. Confirm the successful execution.

Review Checklist:

  • Successfully created a new file hello.js.
  • Wrote a JavaScript script in hello.js for a personalized greeting.
  • Executed the job using the provided command.
  • Verified the correct logs in the CLI output.

🏆 Fetch and inspect data via HTTP​

Overview:

Write a job to fetch user data from the JSONPlaceholder API using OpenFn http adaptor.

Objective:

Fetch and print the details of the first user from the JSONPlaceholder API.

Requirements:

  1. Install the latest version of http adaptor.
openfn repo install @openfn/language-http
  1. Utilize the JSONPlaceholder API.
  2. Create a file named getUsers.js to contain the script.

Tasks:

  1. Create a file (getUsers.js) to house the script.
  2. Fetch a list of users from the JSONPlaceholder API.
  3. Print the details of the first user.
  4. Run the job using OpenFn/cli: openfn getUsers.js -a http -o tmp/output.json.
  5. Validate the expected CLI logs.

Review Checklist:

  • Successful retrieval of user data.
  • Correct printing of the first user's details.
  • Proper use of the OpenFn http adaptor functions.
  • Verified the correct logs in the CLI output.

🏆 Retrieve Covid-19 metadata​

Overview:

Fetch and present COVID-19 metadata using The Atlantic's COVID Tracking Project API.

Objective:

Write a job that retrieves COVID-19 data from the API and calculate some aggregate values across a length of time of your chosing.

Requirements:

  1. Install the latest version of http adaptor.
openfn repo install @openfn/language-http

Tasks:

  1. Write an OpenFn operation to pull COVID-19 metadata from the The Atlantic's COVID Tracking Project API.
    • Utilize https://api.covidtracking.com as your baseUrl in state.configuration.
  2. Run the job using the OpenFn CLI with the command openfn your_operation_file.js -a http -o tmp/output.json.
  3. Evaluate the output and explore different ways to format or present the COVID-19 data by region.

Review Checklist:

  • Successfully created an OpenFn operation file.
  • Implemented code to retrieve COVID-19 metadata from the provided API.
  • Executed the job using the provided CLI command.
  • Explored various formatting or display options for the obtained data.

Feel free to experiment with the data presentation to enhance your understanding. Good luck! 🌐🦠

🏆 Extract names & emails​

Overview:

In this challenge, you will use the JSONPlaceholder API to fetch comments for a specific post (post ID 1). Your task is to extract the "name" and "email" fields from each comment and log the extracted data.

Objective:

Write a job that retrieves comments for post ID 1, extracts the "name" and "email" fields from each comment, and logs the extracted data.

Requirements:

  • Basic knowledge of JavaScript.
  • OpenFn CLI installed on your machine.

Tasks:

  1. Get Post Comments:

  2. Extract Name and Email:

    • Write a function to extract the "name" and "email" fields from each comment.

  3. Log Extracted Data:

    • Log the extracted data (name and email) from each comment to the console.

Review Checklist:

  • Successfully fetched comments for post ID 1.
  • Implemented a function to extract "name" and "email" from comments.
  • Logged the extracted data to the console.

🏆 Control error messages​

Debug what is causing an error on the following line of code and display the error message

// Get post where id is 180
get('posts/180');

🏆 Data transformation and cleaning​

Overview:

In this challenge, you will use JavaScript global array methods, specifically Array.reduce, Array.filter, or Array.map, to create a series of operations that fetch and filter posts by user ID.

Objective:

Write a job that retrieves posts by a specified user ID 1

Requirements:

  1. Utilize JSONPlaceholder API https://jsonplaceholder.typicode.com.
  2. Install the latest version of http adaptor.
openfn repo install @openfn/language-http

Tasks:

  1. Create File:

    • Create a file named getPosts.js for your job.

  2. Get All Posts:

    • Add the first operation to fetch all posts. Use the provided API or any other source of your choice that provides a list of posts.

  3. Filter Posts by ID:

    • Add a second operation with a function that filters posts by user ID. You can use Array.filter or any other suitable method for this task.

  4. Fetch Posts for User ID 1:

    • Use the function from the second operation to filter posts for user ID 1.

Review Checklist:

  • Created getPosts.js file.
  • Successfully fetched all posts.
  • Implemented a function to filter posts by user ID.
  • Retrieved posts for user ID 1.