Problem of JSON parameters in HTTP request when trying to post to linkedin

Chinwe_Nwokoro · August 27, 2025, 6:49am

Describe the problem/error/question

Hey chat so i’m having issues executing a http request to linkedin because of the JSON error

What is the error message (if any)?

It keeps sayong JSON parameter needs to be valid JSON. ive checked the reples on here and nothing has worked so far

Please share your workflow

(Select the nodes on your canvas and use the keyboard shortcuts CMD+C/CTRL+C and CMD+V/CTRL+V to copy and paste the workflow.){
  "nodes": [
    {
      "parameters": {
        "method": "POST",
        "url": "https://api.linkedin.com/v2/ugcPosts",
        "authentication": "predefinedCredentialType",
        "nodeCredentialType": "linkedInOAuth2Api",
        "sendHeaders": true,
        "headerParameters": {
          "parameters": [
            {
              "name": "Authorization",
              "value": "Bearer {AQW0a2Z0NS0FHEgvc7aqB5bHlsvn2j5IRqMRTk38rVJp7vEC3jPlHQA2A9w5ZyBpGl9quooIWqH7kLnAVVpoo3FhWBEQoeghsGMSEfp0nfTpnk1TbdpUfgl4mBzcj6ik1bvaYw9Ab-3Vl9vlH3DqAUbbngt4k-M8BC_lMdH0dTlcjopiVvWy63pNdI9rBKnFb3_FxphRu7RfO6JNMk_kCbmaKpivrrR9tnfCGw5hbfRc5Y5ydLaieeNcg24_XhV6oD5x-upVyqYg3ZzL0q5kER4iDe3KYRwCr09OAjHJdeQHo_nEMerP2qiX8LN79en4CJNGcOO5hwhGStH_nFoSnmNWAMXEfA}"
            },
            {
              "name": "X-Restli-Protocol-Version",
              "value": "2.0.0"
            }
          ]
        },
        "sendBody": true,
        "specifyBody": "json",
        "jsonBody": "=\n{\n\"author\": \"urn:li:person:hfMGWGx_ow\",\n\"lifecycleState\": \"PUBLISHED\",\n\"specificContent\": {\n\"com.linkedin.ugc.ShareContent\": {\n\"media\": [\n{\n\"media\": \"urn:li:digitalmediaAsset:C5603AQHMl0UPKaPusw\",\n\"status\": \"READY\",\n\"title\": {\n\"attributes\": [],\n\"text\": \"Sample Video Create https://drive.google.com/file/d/1MPjwpomkkOBeGx5xWPgAZfO3EYIFZFUy/view?usp=sharing\"\n}\n}\n],\n\"shareCommentary\": {\n\"attributes\": [],\n\"text\": \"{{ $json.Caption }}\"\n},\n\"shareMediaCategory\": \"VIDEO\"\n}\n},\n\"visibility\": {\n\"com.linkedin.ugc.MemberNetworkVisibility\": \"PUBLIC\"\n}\n} }}}",
        "options": {}
      },
      "type": "n8n-nodes-base.httpRequest",
      "typeVersion": 4.2,
      "position": [
        64,
        176
      ],
      "id": "9a5afe71-6a90-49a5-8aab-fbc34b172c1b",
      "name": "HTTP Request1",
      "credentials": {
        "linkedInOAuth2Api": {
          "id": "Cwvr4xK4pCJjlAv4",
          "name": "LinkedIn account 2"
        },
        "linkedInCommunityManagementOAuth2Api": {
          "id": "abvivQvfwdjQCAP1",
          "name": "LinkedIn Community Management account"
        }
      }
    }
  ],
  "connections": {
    "HTTP Request1": {
      "main": [
        []
      ]
    }
  },
  "pinData": {},
  "meta": {
    "templateCredsSetupCompleted": true,
    "instanceId": "35ae3fe36b48e014c41aaf1c49b2748f208955a93f8c3f63d04a12883462b1b1"
  }
}

Share the output returned by the last node

Information on your n8n setup

n8n version: 1.108.1
Database (default: SQLite):
n8n EXECUTIONS_PROCESS setting (default: own, main): own
Running n8n via (Docker, npm, n8n cloud, desktop app): n8n cloud
Operating system: windows 10

mohamed3nan · August 27, 2025, 8:58am

Hi @Chinwe_Nwokoro welcome to the community!

Try using this:

"text":  {{ JSON.stringify( $json.Caption ) }}

Also note that you can use the built-in Linked node to create a post,

Let me know if you still have any issues..

Chinwe_Nwokoro · August 27, 2025, 9:18am

It still gives that same error. This is what it looks like

Chinwe_Nwokoro · August 27, 2025, 9:19am

For the LinkedIn node I tried that and I had issues with credentials. The standard OAuth path stopped me from stopping while the community API said not enough callbacks even after I had created an app and added the client ID and secret

mohamed3nan · August 27, 2025, 9:20am

Hi, replace this please:

with this:

"text":  {{ JSON.stringify( $json.Title) }}

or just:

"text":  "title test"

Chinwe_Nwokoro · August 27, 2025, 9:26am

I have done both and it’s still the same error

Should I copy the whole code on here

mohamed3nan · August 27, 2025, 9:33am

can you try this sample workflow:

you need to link Linkedin OAuth2 API

Chinwe_Nwokoro · August 27, 2025, 10:07am

For this specific get URN it said forbidden something about the credentials. But I have a LinkedIn urn that I was able to get from my own httt request