cURL




Lesson Objectives

  1. Describe what cURL is
  2. Describe when we might use cURL
  3. Use cURL to test a GET request
  4. Use cURL to test a POST request
  5. Pass parameters to the server using cURL



Describe what cURL is

  • Is a command line tool that acts like a browser
  • You can use it to make requests to a website
  • All it does is take the response and writes it to the terminal
    • no formatting



Describe when we might use cURL

  • You want to create a route and test that it works
    • with a GET request, you can just type the route into the URL bar in the browser and see if it works
  • In order to test routes like POST:
    • you can't just make the request in the browser by entering the path in the URL bar like you would with a GET request
      • doing that always makes a GET request
    • the only way to test a POST request in the browser is via forms
      • you have to write a bunch of code that will lead you up to the point where the POST request is made:
        1. create a /new route
        2. create a new.ejs file with forms
        3. have the forms point to the correct POST route
        4. go to the /new route in the browser
        5. fill out the form
        6. click submit
  • With cURL, we can make a POST request directly to the server without needing to go through all the set up



Use cURL to test a GET request

Within the terminal execute the following:

curl https://generalassemb.ly



Use cURL to test a POST request

Set up the following route handler in our app:

app.post("/products", (req, res) => {
  console.log("Create route accessed!")
  res.send("This route works")
})

To make a POST request, we'll need to add some arguments to the terminal command

curl -X POST localhost:3000/products

The -X POST argument tells curl to make a POST request to the server




Pass parameters to the server using cURL

Using the above command, the body of the request will be empty

app.post("/products", (req, res) => {
  console.log("Create route accessed!")
  console.log("Req.body is: ", req.body)
  res.send(req.body)
})

If we want to send in data we need to do so like this:

curl -X POST -d name="bling" localhost:3000/products

or

curl -X POST -d name="bling" -d price="cash money" localhost:3000/products

For each new key/value pair, add a new -d property="value" argument

curl -X POST -d name="kiwi" -d color="green" -d readyToEat="on" localhost:3000/fruits



References

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Created by DanielJS