Using slack webhook with node - slack

Question

I am trying to use slack webhook. I can read a lot of variation about how I should proceed, but until now, none of them worked properly.
I am using the request node module to make the api call, but I can change if needed.
First try following this
import request from 'request';
const url = 'https://hooks.slack.com/services/xxx';
const text = '(test)!';
request.post(
{
headers : { 'Content-type' : 'application/json' },
url,
payload : JSON.stringify({ text }),
},
(error, res, body) => console.log(error, body, res.statusCode)
);
I get : null 400 'invalid_payload'
Next try following this
request.post(
{
headers : { 'Content-type' : 'application/json' },
url,
form : JSON.stringify({ text }),
},
(error, res, body) => console.log(error, body, res.statusCode)
);
This time, it works, but Slack displays: %28test%29%21 instead of (test)!
Did I miss something?

Answer 1

Based on your second example and the working Postman request this is how I got it to work, forgive my change to require as I am running older node version right now. I am not exactly sure what your data would look like that you want to post to Slack, that may change how you want to assemble this.
const request = require('request');
const url = 'https://hooks.slack.com/services/xxxxx';
const text = '(test)!';
request.post(
{
headers : { 'Content-type' : 'application/json' },
url,
form : {payload: JSON.stringify({ text } )}
},
(error, res, body) => console.log(error, body, res.statusCode)
);
If you want to use request you may want to check how slack-node is posting the data, here the relevant snipped from slack-node
Slack.prototype.webhook = function(options, callback) {
var emoji, payload;
emoji = this.detectEmoji(options.icon_emoji);
payload = {
response_type: options.response_type || 'ephemeral',
channel: options.channel,
text: options.text,
username: options.username,
attachments: options.attachments,
link_names: options.link_names || 0
};
payload[emoji.key] = emoji.val;
return request({
method: "POST",
url: this.webhookUrl,
body: JSON.stringify(payload),
timeout: this.timeout,
maxAttempts: this.maxAttempts,
retryDelay: 0
}, function(err, body, response) {
if (err != null) {
return callback(err);
}
return callback(null, {
status: err || response !== "ok" ? "fail" : "ok",
statusCode: body.statusCode,
headers: body.headers,
response: response
});
});
};

Answer 2

You can try the slack-node module, wraps the post to the hook. Here a reduced modified real world example I used to push notifications for AWS instances.
[EDIT] Changed to use your text
Now, using slack-node, you assemble the {} yourself, adding text: and other parameters yourself and pass it to .webhook
const Slack = require('slack-node');
const webhookUri = 'https://hooks.slack.com/services/xxxxx';
const slack = new Slack();
slack.setWebhook(webhookUri);
text = "(test)!"
slack.webhook({
text: text
// text: JSON.stringify({ text })
}, function(err, response) {
console.log(err, response);
});

Answer 3

I finally went with Slack-webhook that I liked better than slack-node. The solution of d parolin is the best answer to my question, but I wanted to mention the work of pthm for completion.