Making HTTP Requests

While creating nodes it is very commonn to call external APIs or make HTTP requests to other services.

This plays a major role during node development, maintenance, and improvements.

We provide a very flexible helper for making HTTP requests that abstracts away most of the complexity with a simple to use interface.

How to use

In the node code, inside the execute function you can easily call:

const response = await this.helpers.httpRequest(options);

Where options is an object in this format:

{
    url: string;
    headers?: object;
    method?: 'GET' | 'POST' | 'PUT' | 'DELETE' | 'HEAD';
    body?: FormData | Array | string | number | object | Buffer | URLSearchParams;
    qs?: object;
    arrayFormat?: 'indices' | 'brackets' | 'repeat' | 'comma';
    auth?: {
        username: string,
        password: string,
    };
    disableFollowRedirect?: boolean;
    encoding?: 'arraybuffer' | 'blob' | 'document' | 'json' | 'text' | 'stream';
    skipSslCertificateValidation?: boolean;
    returnFullResponse?: boolean;
    proxy?: {
        host: string;
        port: string | number;
        auth?: {
            username: string;
            password: string;
        },
        protocol?: string;
    };
    timeout?: number;
    json?: boolean;
}   

Where url is the only mandatory field. The default method is GET.

Some notes about the possible fields:

• body: You can use a regular Javascript Object for JSON payload, a Buffer for file uploads, an instance of FormData for multipart/form-data and URLSearchParams for application/x-www-form-urlencoded.
• headers: A simple key-value pair.
  • If body is an instance of FormData then content-type: multipart/form-data is injected automatically.
  • If body is an instance of URLSearchParams, then content-type: application/x-www-form-urlencoded is added.
  • To override this behavior, you can set any content-type header you wish and it won't be overridden.
• arrayFormat: If your query string contains an array of data, let's say const qs = {IDs: [15,17]}, the values set to arrayFormat define how it will be sent.
  • indices (default): { a: ['b', 'c'] } will be formatted as a[0]=b&a[1]=c
  • brackets: { a: ['b', 'c'] } will be formatted as a[]=b&a[]=c
  • repeat: { a: ['b', 'c'] } will be formatted as a=b&a=c
  • comma: { a: ['b', 'c'] } will be formatted as a=b,c
• auth: Used for Basic auth. Provide username and password.
• disableFollowRedirect: By default, we'll follow redirects. You can set this to false to prevent this from happening
• skipSslCertificateValidation: Used for calling HTTPS services without proper certificate
• returnFullResponse: Instead of returning only the body, returns an object with more data in the following format: {body: body, headers: object, statusCode: 200, statusMessage: 'OK'}
• encoding: We usually detect the content type correctly but you can specify arrayBuffer to receive a Buffer you can read from and interact with.

Deprecation of the previous helper

The previous helper implementation using this.helpers.request(options) used and exposed the request-promise library which was deprecated.

In an effort to keep maximum compatibility, we made a transparent conversion to another library called axios.

If you are having issues, please report them in our Community Forums or on Github.

Also, you can temporarily enable Doc² to use the deprecated library by setting the environment variable WF²_USE_DEPRECATED_REQUEST_LIB=true.

Please note: This behavior is permanent and we will be removing the request-promise library entirely in the future so please report any errors you have so we can fix them.

Migration guide to the new helper

As mentioned above, the previous helper is deprecated and will be replaced in the future. The new helper is much more robust, library agnostic, and easier to use.

New nodes should all use the new helper, and if you have built custom nodes we strongly suggest you migrate to the new helper. Here are the main considerations when migrating:

• Only url is accepted. Previously uri was also accepted
• encoding: null now must be encoding: arrayBuffer
• rejectUnauthorized: false is now skipSslCertificateValidation: true
• Use body according to content-type headers to clarify what is being sent
• resolveWithFullResponse is now returnFullResponse and has similar behavior

Example

For an example, please check the Mattermost node.