Development of an integration modoule in Odoo

I would like a quotation of a module in odoo to allow to call an external webservice upon two events:
- New document stored (from the standard documents module)
- When a new requisition is created (procurement module)
This event should trigger:
1. The creation of a JSON file with the relevant information of the event.
2. A call to a local executable for processing of the JSON.
3. A call to a webservice with the processed JSON.

We require the source code of the module with a license to modify it if it is required.
The software should be compliant with Odoo 12 Community Edition.

These are the API spec.
Name: API A
Version: 0.1
Format: JSON
Method: rest, post
format:
{
    "event": {
        "timestamp": <unix timestamp>,
        "origin": {
            "id": "<hardcoded id number configured>",
        “data”: {
            “variable”: “newrequisition",
            “value”: <value>,
            “message”: “'company':'<company>', 'supplier':'<supplier'>,'id':'<id>'”}
        }
    }
}

name:  api b
version: 0.1
Format: JSON
Method: REST, POST
Format:
{
    "file": {
        "hash_sha256": <Unix timestamp>,
        "file": “<File encoded in Base 64>”,
        “message”: “'name':'<filename>'”
    }
}