Mod publish API
Category: Experimental API
The mod publish API is used to add new mods to the Factorio mod portal. It requires an API key with the ModPortal: Publish Mods usage, which can be created on https://factorio.com/profile. 
It accepts multipart/form-data HTTP requests and responds with JSON encoded objects.
Endpoints
init_publish
| URL | https://mods.factorio.com/api/experimental/mods/init_publish | 
| HTTP Method | POST | 
HTTP Request Header
| Authorization | Bearer $APIKey | Authorization header with the APIKey and a "Bearer " prefix -> "Bearer $APIKey" | 
HTTP Request Body
| mod | string | Name of the mod that will be published. | 
JSON object response
| upload_url | string | URL the mod zip file should be uploaded to | 
| error | string | This attribute only appears on failed requests. | 
| message | string | This attribute only appears on failed requests. Has details about the problem. | 
finish_upload
| URL | $upload_urlURL returned by the init_publish endpoint | 
| HTTP Method | POST | 
HTTP Request Body
| file | file | Mod zip file | 
| description | string, optional | Mod description in markdown format | 
| category | enum, optional | Mod category, See Mod details API#Category | 
| license | enum, optional | Mod category, See Mod details API#License | 
| source_url | url, optional | Url to mod source code repository | 
JSON object response
| success | bool | This attribute only appears on successful uploads. It's set to true. | 
| url | string | This attribute only appears for successful requests. URL path to get mod details endpoint | 
| error | string | This attribute only appears on failed uploads. | 
| message | string | This attribute only appears on failed uploads. Has details about the problem. | 
Possible API Error Responses
Possible values for the error property of API responses
| InvalidApiKey | Missing or invalid API key for the current endpoint | 
| InvalidRequest | Invalid request. | 
| InternalError | Internal error, please try again later. | 
| Forbidden | Insufficent permission for current endpoint | 
| Unknown | Unknown error, please try again later. | 
| InvalidModRelease | Invalid release data in info.json | 
| InvalidModUpload | Invalid mod data in zipfile | 
| ModAlreadyExists | Mod name already exists in mod portal | 
Python example
MOD_PORTAL_URL = "https://mods.factorio.com"
INIT_UPLOAD_URL = f"{MOD_PORTAL_URL}/api/experimental/mods/init_publish"
apikey = getenv("MOD_UPLOAD_API_KEY")
modname = sys.argv[1]
filepath = sys.argv[2]
request_body = data = {"mod": modname}
request_headers = {"Authorization": f"Bearer {apikey}"}
response = requests.post(INIT_UPLOAD_URL, data=request_body, headers=request_headers)
if not response.ok:
    print(f"init_upload failed: {response.text}")
    sys.exit(1)
upload_url = response.json()["upload_url"]
with open(filepath, "rb") as f:
    request_body = {"file": f}
    response = requests.post(upload_url, files=request_body, data={"description": "# published via API"})
if not response.ok:
    print(f"upload failed: {response.text}")
    sys.exit(1)
print(f"upload successful: {response.text}")