Update Attachment in Knowledge Folder

Replace an existing file in a Knowledge base with a new version

PATCH /knowledge/{folderId}

Update a file in a knowledge folder

cURL

curl --request PATCH \
  --url https://api.langdock.com/knowledge/{folderId} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: multipart/form-data' \
  --form file='@example-file' \
  --form 'url=<string>' \
  --form 'attachmentId=<string>'

import requests

url = "https://api.langdock.com/knowledge/{folderId}"

files = { "file": ("example-file", open("example-file", "rb")) }
payload = {
    "url": "<string>",
    "attachmentId": "<string>"
}
headers = {"Authorization": "Bearer <token>"}

response = requests.patch(url, data=payload, files=files, headers=headers)

print(response.text)

const form = new FormData();
form.append('file', '<string>');
form.append('url', '<string>');
form.append('attachmentId', '<string>');

const options = {method: 'PATCH', headers: {Authorization: 'Bearer <token>'}};

options.body = form;

fetch('https://api.langdock.com/knowledge/{folderId}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.langdock.com/knowledge/{folderId}",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "PATCH",
  CURLOPT_POSTFIELDS => "-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"file\"; filename=\"example-file\"\r\nContent-Type: application/octet-stream\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"url\"\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"attachmentId\"\r\n\r\n<string>\r\n-----011000010111000001101001--",
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: multipart/form-data"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.langdock.com/knowledge/{folderId}"

	payload := strings.NewReader("-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"file\"; filename=\"example-file\"\r\nContent-Type: application/octet-stream\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"url\"\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"attachmentId\"\r\n\r\n<string>\r\n-----011000010111000001101001--")

	req, _ := http.NewRequest("PATCH", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.patch("https://api.langdock.com/knowledge/{folderId}")
  .header("Authorization", "Bearer <token>")
  .body("-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"file\"; filename=\"example-file\"\r\nContent-Type: application/octet-stream\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"url\"\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"attachmentId\"\r\n\r\n<string>\r\n-----011000010111000001101001--")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.langdock.com/knowledge/{folderId}")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Patch.new(url)
request["Authorization"] = 'Bearer <token>'
request.body = "-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"file\"; filename=\"example-file\"\r\nContent-Type: application/octet-stream\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"url\"\r\n\r\n<string>\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"attachmentId\"\r\n\r\n<string>\r\n-----011000010111000001101001--"

response = http.request(request)
puts response.read_body

Using our API via a dedicated deployment? Just replace api.langdock.com with your deployment’s base URL: <deployment-url>/api/public

The Knowledge Folder API manages resources that appear as Knowledge bases in the Library.

Updates an existing file (attachment) in a Knowledge base by replacing it with a new version. The old file is removed and the new file is processed and embedded.

Requires an API key with the KNOWLEDGE_FOLDER_API scope. The API key itself needs the Editor role on the Knowledge base. See Share Knowledge bases with the API for setup instructions.

Request Format

This endpoint accepts multipart/form-data requests with the file attached.

Path Parameters

Parameter	Type	Required	Description
folderId	string	Yes	The ID of the Knowledge base

Form Fields

Field	Type	Required	Description
attachmentId	string	Yes	The ID of the attachment to update
file	file	Yes	The new file to upload (max 256MB)
url	string	No	URL shown to users when this file is used in an answer

Examples

Update with cURL

curl -X PATCH "https://api.langdock.com/knowledge/{folderId}" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -F "attachmentId=att_abc123def456" \
  -F "file=@/path/to/new-document.pdf"

Update with JavaScript

const FormData = require("form-data");
const fs = require("fs");
const axios = require("axios");

async function updateAttachment(folderId, attachmentId, filePath) {
  const form = new FormData();
  form.append("attachmentId", attachmentId);
  form.append("file", fs.createReadStream(filePath));

  const response = await axios.patch(
    `https://api.langdock.com/knowledge/${folderId}`,
    form,
    {
      headers: {
        Authorization: "Bearer YOUR_API_KEY",
        ...form.getHeaders(),
      },
    }
  );

  return response.data;
}

// Example usage
try {
  const result = await updateAttachment(
    "folder_abc123",
    "att_xyz789",
    "/path/to/updated-report.pdf"
  );
  console.log("Attachment updated:", result);
} catch (error) {
  console.error("Failed to update:", error.response?.data?.message);
}

Update with Source URL

const FormData = require("form-data");
const fs = require("fs");
const axios = require("axios");

async function updateAttachmentWithUrl(folderId, attachmentId, filePath, sourceUrl) {
  const form = new FormData();
  form.append("attachmentId", attachmentId);
  form.append("file", fs.createReadStream(filePath));
  form.append("url", sourceUrl);

  const response = await axios.patch(
    `https://api.langdock.com/knowledge/${folderId}`,
    form,
    {
      headers: {
        Authorization: "Bearer YOUR_API_KEY",
        ...form.getHeaders(),
      },
    }
  );

  return response.data;
}

Response Format

Success Response (200 OK)

{
  status: "success";
  result: {
    id: string;          // Unique attachment ID
    name: string;        // Original filename
    mimeType: string;    // MIME type of the file
    createdAt: string;   // ISO 8601 timestamp
    updatedAt: string;   // ISO 8601 timestamp
    url: string | null;  // Source URL if provided
  };
}

Example Response

{
  "status": "success",
  "result": {
    "id": "att_abc123def456",
    "name": "updated-report.pdf",
    "mimeType": "application/pdf",
    "createdAt": "2025-01-15T10:30:00.000Z",
    "updatedAt": "2025-01-20T14:45:00.000Z",
    "url": null
  }
}

Error Handling

try {
  const response = await updateAttachment(folderId, attachmentId, filePath);
} catch (error) {
  if (error.response) {
    switch (error.response.status) {
      case 400:
        console.error("Invalid request:", error.response.data.message);
        // Possible causes: missing attachmentId, missing file, unsupported file type
        break;
      case 401:
        console.error("Invalid or missing API key");
        break;
      case 403:
        console.error("API key does not have access to this Knowledge base");
        break;
      case 404:
        console.error("Knowledge base or attachment not found");
        break;
      case 408:
        console.error("Upload request timed out");
        break;
      case 413:
        console.error("File size exceeds 256MB limit");
        break;
      case 429:
        console.error("Rate limit exceeded");
        break;
      case 500:
        console.error("Server error");
        break;
    }
  }
}

Processing Status

After updating, the new file is processed asynchronously. Use the Retrieve Files endpoint to check processing status. The syncStatus field indicates the current state:

• UPLOADING - File is being uploaded
• UPLOADED - File is uploaded and queued for processing
• EXTRACTING - Text is being extracted from the file
• EMBEDDING - Embeddings are being generated
• SYNCED - File is ready for search
• ACTION_FAILED, EXTRACTION_FAILED, EMBEDDING_FAILED, TIMEOUT - Processing failed

Langdock intentionally blocks browser-origin requests to protect your API key and ensure your applications remain secure. For more information, please see our guide on API Key Best Practices.

Authorizations

Authorization · string · header · required

API key as Bearer token. Format "Bearer YOUR_API_KEY"

Path Parameters

folderId · string · required

The ID of the knowledge folder

Body

multipart/form-data

file · file

The new file to upload

url · string

URL that is shown to the user if the file is used in an answer

attachmentId · string

The ID of the attachment to update

Response

200

Attachment updated successfully