Open APIs

Hi All,

What is TMF recommendation on having more than one active versions of an API. Would like to know TMF view on 
1. How long an old version should be available for customers. What is the industry practice
2. What should be the frequency of new API version releases. What is the industry practice
3. Any common pitfalls associated with API version co-existence

Best Regards,

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Kalpana HV
Colt Technology Services
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Hi Kalpana

The Open API maintains previous versions of the API definitions at these places (here and here). I am not sure what the official policy is for maintaining these definitions (i.e. for how long would there be fixing and republishing if a defect was found), perhaps @Alan Pope can shed light on TMF policy for its deliverables in general.

The main challenge, of course, is not for the organization (such as TMF) that simply defines APIs, but rather for the API implementors (such as vendors or CSPs)​.
Backwards-incompatible changes (such as were done in many APIs in the v4 series) cause implementors to consider whether to maintain multiple implementations for the different versions, and how this can be done. Vendors, in particular, will have to contend with their obligations to multiple customers, some of whom expect the latest version to be supported while others are still working with earlier versions. It is "easier" if the need is to support only a single version in one deployment, it is then "simply" a question of resources (people and money) to invest in maintaining multiple development branches. It is more difficult if the same provider deployment needs to support multiple incompatible versions, it might be technically challenging to achieve this, depending on the nature of the change.

Hope it helps.

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Jonathan Goldberg
Amdocs Management Limited
Any opinions and statements made by me on this forum are purely personal, and do not necessarily reflect the position of the TM Forum or my employer.
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Thank you @Jonathan Goldberg for the inputs.

Best Regards, ​​

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Kalpana HV
Colt Technology Services
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Original Message:
Sent: Nov 15, 2020 00:40
From: Jonathan Goldberg
Subject: Version co existence

Hi Kalpana

The Open API maintains previous versions of the API definitions at these places (here and here). I am not sure what the official policy is for maintaining these definitions (i.e. for how long would there be fixing and republishing if a defect was found), perhaps @Alan Pope can shed light on TMF policy for its deliverables in general.

The main challenge, of course, is not for the organization (such as TMF) that simply defines APIs, but rather for the API implementors (such as vendors or CSPs)​.
Backwards-incompatible changes (such as were done in many APIs in the v4 series) cause implementors to consider whether to maintain multiple implementations for the different versions, and how this can be done. Vendors, in particular, will have to contend with their obligations to multiple customers, some of whom expect the latest version to be supported while others are still working with earlier versions. It is "easier" if the need is to support only a single version in one deployment, it is then "simply" a question of resources (people and money) to invest in maintaining multiple development branches. It is more difficult if the same provider deployment needs to support multiple incompatible versions, it might be technically challenging to achieve this, depending on the nature of the change.

Hope it helps.

------------------------------
Jonathan Goldberg
Amdocs Management Limited
Any opinions and statements made by me on this forum are purely personal, and do not necessarily reflect the position of the TM Forum or my employer.
------------------------------