nocin.eu

Homelab, Linux, JS & ABAP (~˘▾˘)~
 

[nodejs] iterate through fetch response headers

https://github.github.io/fetch/#Headers

        const response = await fetch("https://example.com/api")

        for (const [key, value] of response.headers) {
            console.log(key, value)
          }

An alternative would be forEach()

        response.headers.forEach((value, key) => {
            console.log(value, key)
        })

Or using the entries() iterator (ES8)

          const headerIterator = response.headers.entries()
          console.log(headerIterator.next().value)
          console.log(headerIterator.next().value)

To add a new header just use set()

response.set(key, value)

[JavaScript] Download base64 encoded file within a browser

            const sBase64 = "JVBERi0xLjQKJcOkw7zDtsOfCjIgMCBvYmoKPDwvTGVuZ3....."
            const arrayBuffer = new Uint8Array([...window.atob(sBase64)].map(char => char.charCodeAt(0)))
            const fileLink = document.createElement('a')

            fileLink.href = window.URL.createObjectURL(new Blob([arrayBuffer]))
            fileLink.setAttribute('download', "example.pdf")
            document.body.appendChild(fileLink)
            fileLink.click()

Or use the npm package FileSaver.

import { saveAs } from "file-saver";

const sBase64 = "JVBERi0xLjQKJcOkw7zDtsOfCjIgMCBvYmoKPDwvTGVuZ3....."
const buffer = Buffer.from(sBase64, "base64") //Buffer is only available when using nodejs
saveAs(new Blob([buffer]), "example.pdf")

[JavaScript] map an array of objects to return an array of objects

Recently I hat to create an array of objects from another array of objects to change some property names and to enrich it with some values. To iterate over the array I used the map() function. But when trying to return the new object using the brackets {}, the map function instead expects me trying to write a function… Therefore you need to wrap the return object in ()

const aPersons = [{
  id: 1,
  name: 'max'
}, {
  id: 2,
  name: 'peter'
}]

const aResult = aPersons.map(person => ({ value: person.id, text: person.name, someboolean: true }))
console.log(aResult)

[CAP] Set credentials in package.json via .env

https://developers.sap.com/tutorials/btp-app-ext-service-add-consumption.html#ebedc445-68de-4cd2-befd-6e31897852a8

These three entries in a .env file

cds.requires.ECEmploymentInformation.[development].credentials.authentication=BasicAuthentication
cds.requires.ECEmploymentInformation.[development].credentials.username=myUsername
cds.requires.ECEmploymentInformation.[development].credentials.password=myPassword

are equal to line 12, 13, and 14 in this package.json snippet:

{
    "cds": {
      "ECEmploymentInformation": {
        "kind": "odata-v2",
        "model": "srv/external/ECEmploymentInformation",
        "credentials": {
          "[production]": {
            "destination": "sfsf"
          },
          "[development]": {
            "url": "https://apisalesdemo2.successfactors.eu/odata/v2",
            "authentication": "BasicAuthentication",
            "username": "myUsername",
            "password": "myPassword",
          }
        }
      }
    }
}

[Linux Mint] Sharkoon PureWriter Keyboard not recognized after suspend

In January 2020 I bought a Sharkoon PureWriter Keyboard and since then I had the problem that the keyboard got not recognized after my PC (which runs on Linux Mint) was coming back from suspend mode. Back then I couldn’t find a solution and was just hoping that a newer kernel release will fix this problem in the future. But it did not. So today I was searching again and stumbled again across this post, but now I noticed the new answer from April this year. And it finally solved it!

https://askubuntu.com/questions/1044988/usb-ports-not-working-after-resume-from-sleep-on-ubuntu-18-04

First check with usbreset for the device name and then create the script under the following path:

sudo micro /lib/systemd/system-sleep/reset-keyboard 
#!/bin/sh

case $1 in
  post)
    usbreset "USB-HID Keyboard"
    ;;
esac

And as a last step we make it executable:

sudo chmod +x /lib/systemd/system-sleep/reset-keyboard

[SAPUI5] Parse error message

If the error response is type json:

        oModel.callFunction("/myFunction", {
          method: "GET",
          urlParameters: {
            ID: myID,
          },
          success: oData => console.log(oData),
          error: oError => MessageBox.error(JSON.parse(oError.responseText).error.message.value, { title: "An error occurred" })
        });

If the error response is coming from a Gateway and has an XML body (link):

 MessageBox.error(jQuery.parseXML(oError.response.body).querySelector("message").textContent)

[Postman] Visualize base64 image

If you have a service which returns a payload like the following (including a base64 encoded jpeg) you can display it directly in postman.

{
        "photo": "/9j/4AAQSkZJRgABAgAAAQABAAD/2wBDAAMCAgMCAgMDAwMEAwMEBQgFBQQEBQoHBwYIDAoMDAsK\r\nCwsND..............",
        "photoId": "192",
        "mimeType": "image/jpeg"
}

This can be done with a few lines of code. In Postman navigate to the “Tests” tab:

and insert the following lines:

//output to postman console
console.log("PhotoId: " + pm.response.json()["photoId"]);
console.log("Base64: " + pm.response.json()["photo"]);

//output in visualize tab
let template = `<img src='{{img}}'/>`;

pm.visualizer.set(template, { 
    img: `data:image/jpeg;base64,${pm.response.json()["photo"]}`
});

In the “Visualize” tab you should now find your image