OCPI 2.2.1-d2 Chapter 5

Status Codes

Based on OCPI 2.2.1-d3-pre1 Specification. This chapter covers the HTTP transport status codes and OCPI content-level status codes, including success, client error, server error, and hub error code ranges.

5 Sections

4-digit OCPI Codes

1xxx - 4xxx Ranges

1. Overview

Introduction

There are two types of status codes used in OCPI:

Transport vs Content Status Codes

Transport Related (HTTP)

The transport layer ends after a message is correctly parsed into a (semantically unvalidated) JSON structure. When a message does not contain a valid JSON string, the HTTP error 400 - Bad Request MUST be returned.

Content Related (OCPI)

If a request is syntactically valid JSON and addresses an existing resource, a HTTP error MUST NOT be returned. Those requests are supposed to have reached the OCPI layer.

HTTP Response Codes: In case of a GET request, when the resource does NOT exist, the server SHOULD return a HTTP 404 - Not Found. When the server receives a valid OCPI object it SHOULD respond with:

HTTP 200 - Ok when the object already existed and has successfully been updated.
HTTP 201 - Created when the object has been newly created in the server system.

Requests that reach the OCPI layer SHOULD return an OCPI response message with a status_code field as defined below.

Status Code Ranges

Range	Description
`1xxx`	Success
`2xxx`	Client errors — The data sent by the client can not be processed by the server
`3xxx`	Server errors — The server encountered an internal error

Data Field Behaviour

NOTE: Custom status code range values SHALL NOT be used by standard OCPI modules as described in this document! When custom status codes are used, keep in mind that different custom modules could use the same values with a different meaning, as they are not standardized.

When the status code is in the success range (1xxx), the data field in the response message SHOULD contain the information as specified in the protocol. Otherwise the data field is unspecified and MAY be omitted, set to null or something else that could help to debug the problem from a programmer's perspective. For example, it could specify which fields contain an error or are missing.

2. 1xxx: Success

5.1

Success Codes

Code	Description
`1000`	Generic success code
`19xx`	Reserved range for custom success status codes (1900-1999).

3. 2xxx: Client Errors

5.2

Errors detected by the server in the message sent by a client where the client did something wrong.

Client Error Codes

Code	Description
`2000`	Generic client error
`2001`	Invalid or missing parameters, for example: missing `last_updated` field in a PATCH request.
`2002`	Not enough information, for example: Authorization request with too little information.
`2003`	Unknown Location, for example: Command: `START_SESSION` with unknown location.
`2004`	Unknown Token, for example: 'real-time' authorization of an unknown Token.
`29xx`	Reserved range for custom client error status codes (2900-2999).

4. 3xxx: Server Errors

5.3

Error during processing of the OCPI payload in the server. The message was syntactically correct but could not be processed by the server.

Server Error Codes

Code	Description
`3000`	Generic server error
`3001`	Unable to use the client's API. For example during the credentials registration: When the initializing party requests data from the other party during the open POST call to its credentials endpoint. If one of the GETs can not be processed, the party should return this error in the POST response.
`3002`	Unsupported version
`3003`	No matching endpoints or expected endpoints missing between parties. Used during the registration process if the two parties do not have any mutual modules or endpoints available, or the minimal implementation expected by the other party is not been met.
`39xx`	Reserved range for custom server error status codes (3900-3999).

5. 4xxx: Hub Errors

5.4

When a server encounters an error, client side error (2xxx) or server side error (3xxx), it sends the status code to the Hub. The Hub SHALL then forward this error to the client which sent the request (when the request was not a Broadcast Push).

For errors that a Hub encounters while routing messages, the following OCPI status codes shall be used.

Hub Error Codes

Code	Description
`4000`	Generic error
`4001`	Unknown receiver (TO address is unknown)
`4002`	Timeout on forwarded request (message is forwarded, but request times out)
`4003`	Connection problem (receiving party is not connected)
`49xx`	Reserved range for custom hub error status codes (4900-4999).