HTTP request

Information on how works HTTP request in REST API component.

HTTP request function

In a REST API component the trigger and action perform the same function - HTTP request witch will send a GET/POST/PUT/PATCH/DELETE requests and parse the response back to the flow.

Output

The messages produced by the REST API component will have the following properties:

headers: Object containing the HTTP response headers
statusCode: HTTP Status Code of the Response. Number between 100 and 599
statusMessage: Human readable equivalent to the response code
body: The contents of the HTTP response body:
- When the content type header includes json, then the result will be parsed into the corresponding object
- When the content type header includes xml, then the result will be converted into the JSON equivalent of the represented XML using the same rules as above
- When the content type header includes one of image, msword, msexcel, pdf, csv, octet-stream or binary the request body contents will be stored as an attachment and there will be no body property in the outgoing message
- When there is no body (because the content-length is 0), then there will be no body property in the outbound message.
- If there is another content type, then the response will be treated as text
- If the content type header is omitted, then an attempt to convert the result to JSON will be made. If that fails, then the result will be treated as if it were text.

For more details you can see the usage example.

Defining request body

If the HTTP method is any other but GET, you will see a Body tab appear next to the Header tab. The Body tab enables configuration options such as the content type drop-down menu and the body input field.

Here is the list of all supported content types:

multipart/form-data
application/x-www-form-urlencoded
text/plain
application/json
application/xml
text/xml
text/html

The body input field changes according to the chosen content type.

Notes:

Response body will be stored in msg.body

Request body that causes empty response body will return {}

Sending JSON data

Here is how to send a JSON data in the body. Change the content type to application/json and the body input part would change accordingly to accept JSON object. Please note that this field supports JSONata expressions.

Configure Input - Body

Example shows the JSON in the body where the name parameter value gets mapped using the value of project_name from the previous step of integration.

Sending XML data

To send an XML data, set the content type to application/xml or text/xml and place the XML in the body input field between double-quotes like:

"
<note>
  <to>" & fname & "</to>
  <from>Jani</from>
  <heading>Reminder</heading>
  <body>Don't forget me this weekend!</body>
</note>
"

Use a JSONata expression to include and map any values coming from the previous steps. It will replace the variable with a real value in the final mapping. Note that the rest of XML gets passed as a string.

Sending Form data

To send a form data, two content types are available:

application/x-www-form-urlencoded - used to submit simple values to a form
multipart/form-data - used to submit (non-alphanumeric) data or file attachment in payload

In both cases the payload gets transmitted in the message body.

In case of application/x-www-form-urlencoded content type, add the necessary parameters by giving the name and the values like:

Sending form data

Please note: the parameter value fields support JSONata expressions.*

This HTTP request would submit key1=value1&key2=value2 in the message body.

In case of multipart/form-data content type, add the parameters similarly.

Sending multipart form data

The transmitted HTTP request body would be:

--__X_BOUNDARY__
Content-Disposition: form-data; name="part1"

Please note that this fields supports [JSONata](http://jsonata.org) expressions.
--__X_BOUNDARY__
Content-Disposition: form-data; name="part2"

<p>Some more text</p>
--__X_BOUNDARY__--

Notice how different parts get separated by the boundary. This form is capable of supporting attachments as well.

Working with XML

This component will try to parse XML content types in the HTTP Response assuming the Content-Type header has a MIME Content Type with xml in it (e.g. application/xml). In this case response body will be parsed to JSON using xml2js node library and following settings:

{
    trim: false,
    normalize: false,
    explicitArray: false,
    normalizeTags: false,
    attrkey: '_attr',
    tagNameProcessors: [
        (name) => name.replace(':', '-')
    ]
}

for more information please see the Documenattion of XML2JS library

HTTP Headers

You can get HTTP response header only if Don`t throw Error on Failed Calls option is checked. In this case output structure of component will be:

    {
      headers:<HTTP headers>,
      body:<HTTP response body>,
      statusCode:<HTTP response status code>
      statusMessage:<HTTP response status message>
    }

Defining HTTP headers

Use this section to add the request headers.

HTTP Headers

Each header has a name and a value. Header name should be colon-separated name-value pairs in clear-text string format. The header value can use JSONata expressions.

Please note: HTTP Response headers will not be stored, the components stores body and attachment only.

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