Marseille16 / REST api
During the first couple Hackfest days, Jonathan, Benjamin and I worked on a reference implementation of CRUD code for a REST endpoint, so others can read it, discuss it and use it as a reference for their own developments. We worked on Koha::Cit(y|ies) because it was a really simple class. All our work is now on bug 17428. The main goals/concepts we tried to apply were: * Controller class (Koha::REST::V1::Cities) should be as simple as possible. No business logic on it. All business logic is expected to be put on the Koha::Cit(ies|y) classes. And fully tested. * All verbs/use cases should be covered by tests (t/db_dependent/api/v1/cities.t). We did it, and this file could be used (with little adjustments) as the basis for new endpoint tests. * Heavy use of exceptions. I wouldn't say we heavily use them, but the point is that we pass everything to the business object, and catch exceptions it might raise. Martin pointed out that he would help us further simplify it, making heavier use of the Swagger plugin's facilities. Specially on parameters sanity check. More on this tomorrow! * Koha::Exceptions got per-class files so the exceptions file is more manageable. Bug 17425 introduced Koha/Exceptions/Object.pm, and we propose that's the way to go (Koha/Exceptions.pm still has Virtualshelves-related exceptions that should be moved). * Make use of Try::Tiny for try/catch blocks. On the process we wrote bug 17425, which introduces new exceptions, we added the dependency for Try::Tiny (no worries, it is packaged for Jessie/Ubuntu) and Mirko was here to validate. * Moving business-logic to Koha:: namespace and write REST endpoints on top of that business objects. We picked a simple object, Koha::Patron(s) will be a more complex one of course. This is what Jonathan has been doing, and people willing to write REST endpoints should check with him, and probably help moving business logic into Koha:: namespace. There are several patches on bugzilla introducing endpoints. We will try to contact patch authors to help them make their work match this proposed 'guidelines'. We are sticking to the 'patches speak' approach, so feel free to criticize this implementation, to improve it or even provide a counter-proposal. We are otherwise moving on, trying to get a functional complete REST api ASAP. Thanks! Tomas, Jonathan, Benjamin -- Tomás Cohen Arazi Theke Solutions (https://theke.io <http://theke.io/>) ✆ +54 9351 3513384 GPG: B2F3C15F
Really curious to see how this plays out! I’ve just added parameter validation to a Koha::Object, and while it works well enough, I’m hoping for a more generalized solution. I haven’t looked at Koha::Exceptions::* yet, but maybe that will help. Peeking at Koha::Exceptions::MissingParameter, I hope that there’s more specificity than just “A required parameter is missing”. I’d want to know which required parameter is missing. Is there a document somewhere saying how to use Koha::Exceptions? David Cook Systems Librarian Prosentient Systems 72/330 Wattle St Ultimo, NSW 2007 Australia Office: 02 9212 0899 Direct: 02 8005 0595 From: koha-devel-bounces@lists.koha-community.org [mailto:koha-devel-bounces@lists.koha-community.org] On Behalf Of Tomas Cohen Arazi Sent: Wednesday, 12 October 2016 2:39 AM To: koha-devel <koha-devel@lists.koha-community.org> Subject: [Koha-devel] Marseille16 / REST api During the first couple Hackfest days, Jonathan, Benjamin and I worked on a reference implementation of CRUD code for a REST endpoint, so others can read it, discuss it and use it as a reference for their own developments. We worked on Koha::Cit(y|ies) because it was a really simple class. All our work is now on bug 17428. The main goals/concepts we tried to apply were: * Controller class (Koha::REST::V1::Cities) should be as simple as possible. No business logic on it. All business logic is expected to be put on the Koha::Cit(ies|y) classes. And fully tested. * All verbs/use cases should be covered by tests (t/db_dependent/api/v1/cities.t). We did it, and this file could be used (with little adjustments) as the basis for new endpoint tests. * Heavy use of exceptions. I wouldn't say we heavily use them, but the point is that we pass everything to the business object, and catch exceptions it might raise. Martin pointed out that he would help us further simplify it, making heavier use of the Swagger plugin's facilities. Specially on parameters sanity check. More on this tomorrow! * Koha::Exceptions got per-class files so the exceptions file is more manageable. Bug 17425 introduced Koha/Exceptions/Object.pm, and we propose that's the way to go (Koha/Exceptions.pm still has Virtualshelves-related exceptions that should be moved). * Make use of Try::Tiny for try/catch blocks. On the process we wrote bug 17425, which introduces new exceptions, we added the dependency for Try::Tiny (no worries, it is packaged for Jessie/Ubuntu) and Mirko was here to validate. * Moving business-logic to Koha:: namespace and write REST endpoints on top of that business objects. We picked a simple object, Koha::Patron(s) will be a more complex one of course. This is what Jonathan has been doing, and people willing to write REST endpoints should check with him, and probably help moving business logic into Koha:: namespace. There are several patches on bugzilla introducing endpoints. We will try to contact patch authors to help them make their work match this proposed 'guidelines'. We are sticking to the 'patches speak' approach, so feel free to criticize this implementation, to improve it or even provide a counter-proposal. We are otherwise moving on, trying to get a functional complete REST api ASAP. Thanks! Tomas, Jonathan, Benjamin -- Tomás Cohen Arazi Theke Solutions (https://theke.io <http://theke.io/> ) ✆ +54 9351 3513384 GPG: B2F3C15F
El mié., 12 oct. 2016 a las 7:26, David Cook (<dcook@prosentient.com.au>) escribió:
Really curious to see how this plays out!
I’ve just added parameter validation to a Koha::Object, and while it works well enough, I’m hoping for a more generalized solution. I haven’t looked at Koha::Exceptions::* yet, but maybe that will help.
I don't know how that would work, what bug number is it?
Peeking at Koha::Exceptions::MissingParameter, I hope that there’s more specificity than just “A required parameter is missing”. I’d want to know which required parameter is missing.
Is there a document somewhere saying how to use Koha::Exceptions?
Well, we are not baking our own exception system, we are just using Class::Exception so it is pretty documented! Look at bug 17425, you will notice when we throw an exception we can add a message. Regards!
David Cook
Systems Librarian
Prosentient Systems
72/330 Wattle St
Ultimo, NSW 2007
Australia
Office: 02 9212 0899 <02%2092%2012%2008%2099>
Direct: 02 8005 0595 <02%2080%2005%2005%2095>
*From:* koha-devel-bounces@lists.koha-community.org [mailto: koha-devel-bounces@lists.koha-community.org] *On Behalf Of *Tomas Cohen Arazi *Sent:* Wednesday, 12 October 2016 2:39 AM *To:* koha-devel <koha-devel@lists.koha-community.org> *Subject:* [Koha-devel] Marseille16 / REST api
During the first couple Hackfest days, Jonathan, Benjamin and I worked on a reference implementation of CRUD code for a REST endpoint, so others can read it, discuss it and use it as a reference for their own developments.
We worked on Koha::Cit(y|ies) because it was a really simple class. All our work is now on bug 17428.
The main goals/concepts we tried to apply were:
* Controller class (Koha::REST::V1::Cities) should be as simple as possible. No business logic on it. All business logic is expected to be put on the Koha::Cit(ies|y) classes. And fully tested.
* All verbs/use cases should be covered by tests (t/db_dependent/api/v1/cities.t). We did it, and this file could be used (with little adjustments) as the basis for new endpoint tests.
* Heavy use of exceptions. I wouldn't say we heavily use them, but the point is that we pass everything to the business object, and catch exceptions it might raise. Martin pointed out that he would help us further simplify it, making heavier use of the Swagger plugin's facilities. Specially on parameters sanity check. More on this tomorrow!
* Koha::Exceptions got per-class files so the exceptions file is more manageable. Bug 17425 introduced Koha/Exceptions/Object.pm, and we propose that's the way to go (Koha/Exceptions.pm still has Virtualshelves-related exceptions that should be moved).
* Make use of Try::Tiny for try/catch blocks. On the process we wrote bug 17425, which introduces new exceptions, we added the dependency for Try::Tiny (no worries, it is packaged for Jessie/Ubuntu) and Mirko was here to validate.
* Moving business-logic to Koha:: namespace and write REST endpoints on top of that business objects. We picked a simple object, Koha::Patron(s) will be a more complex one of course. This is what Jonathan has been doing, and people willing to write REST endpoints should check with him, and probably help moving business logic into Koha:: namespace.
There are several patches on bugzilla introducing endpoints. We will try to contact patch authors to help them make their work match this proposed 'guidelines'.
We are sticking to the 'patches speak' approach, so feel free to criticize this implementation, to improve it or even provide a counter-proposal. We are otherwise moving on, trying to get a functional complete REST api ASAP.
Thanks!
Tomas, Jonathan, Benjamin
--
Tomás Cohen Arazi
Theke Solutions (https://theke.io <http://theke.io/>) ✆ +54 9351 3513384 <+54%209%20351%20351-3384> GPG: B2F3C15F
-- Tomás Cohen Arazi Theke Solutions (https://theke.io <http://theke.io/>) ✆ +54 9351 3513384 GPG: B2F3C15F
Here are my notes : https://wiki.koha-community.org/wiki/Marseille_hackfest_2016#REST_API_-_Thom... Le 12/10/2016 à 09:17, Tomas Cohen Arazi a écrit :
El mié., 12 oct. 2016 a las 7:26, David Cook (<dcook@prosentient.com.au>) escribió:
Really curious to see how this plays out!
I’ve just added parameter validation to a Koha::Object, and while it works well enough, I’m hoping for a more generalized solution. I haven’t looked at Koha::Exceptions::* yet, but maybe that will help.
I don't know how that would work, what bug number is it?
Peeking at Koha::Exceptions::MissingParameter, I hope that there’s more specificity than just “A required parameter is missing”. I’d want to know which required parameter is missing.
Is there a document somewhere saying how to use Koha::Exceptions?
Well, we are not baking our own exception system, we are just using Class::Exception so it is pretty documented!
Look at bug 17425, you will notice when we throw an exception we can add a message.
Regards!
David Cook
Systems Librarian
Prosentient Systems
72/330 Wattle St
Ultimo, NSW 2007
Australia
Office: 02 9212 0899 <02%2092%2012%2008%2099>
Direct: 02 8005 0595 <02%2080%2005%2005%2095>
*From:* koha-devel-bounces@lists.koha-community.org [mailto: koha-devel-bounces@lists.koha-community.org] *On Behalf Of *Tomas Cohen Arazi *Sent:* Wednesday, 12 October 2016 2:39 AM *To:* koha-devel <koha-devel@lists.koha-community.org> *Subject:* [Koha-devel] Marseille16 / REST api
During the first couple Hackfest days, Jonathan, Benjamin and I worked on a reference implementation of CRUD code for a REST endpoint, so others can read it, discuss it and use it as a reference for their own developments.
We worked on Koha::Cit(y|ies) because it was a really simple class. All our work is now on bug 17428.
The main goals/concepts we tried to apply were:
* Controller class (Koha::REST::V1::Cities) should be as simple as possible. No business logic on it. All business logic is expected to be put on the Koha::Cit(ies|y) classes. And fully tested.
* All verbs/use cases should be covered by tests (t/db_dependent/api/v1/cities.t). We did it, and this file could be used (with little adjustments) as the basis for new endpoint tests.
* Heavy use of exceptions. I wouldn't say we heavily use them, but the point is that we pass everything to the business object, and catch exceptions it might raise. Martin pointed out that he would help us further simplify it, making heavier use of the Swagger plugin's facilities. Specially on parameters sanity check. More on this tomorrow!
* Koha::Exceptions got per-class files so the exceptions file is more manageable. Bug 17425 introduced Koha/Exceptions/Object.pm, and we propose that's the way to go (Koha/Exceptions.pm still has Virtualshelves-related exceptions that should be moved).
* Make use of Try::Tiny for try/catch blocks. On the process we wrote bug 17425, which introduces new exceptions, we added the dependency for Try::Tiny (no worries, it is packaged for Jessie/Ubuntu) and Mirko was here to validate.
* Moving business-logic to Koha:: namespace and write REST endpoints on top of that business objects. We picked a simple object, Koha::Patron(s) will be a more complex one of course. This is what Jonathan has been doing, and people willing to write REST endpoints should check with him, and probably help moving business logic into Koha:: namespace.
There are several patches on bugzilla introducing endpoints. We will try to contact patch authors to help them make their work match this proposed 'guidelines'.
We are sticking to the 'patches speak' approach, so feel free to criticize this implementation, to improve it or even provide a counter-proposal. We are otherwise moving on, trying to get a functional complete REST api ASAP.
Thanks!
Tomas, Jonathan, Benjamin
--
Tomás Cohen Arazi
Theke Solutions (https://theke.io <http://theke.io/>) ✆ +54 9351 3513384 <+54%209%20351%20351-3384> GPG: B2F3C15F
_______________________________________________ Koha-devel mailing list Koha-devel@lists.koha-community.org http://lists.koha-community.org/cgi-bin/mailman/listinfo/koha-devel website : http://www.koha-community.org/ git : http://git.koha-community.org/ bugs : http://bugs.koha-community.org/
-- Fridolin SOMERS Biblibre - Pôles support et système fridolin.somers@biblibre.com
Cheers, Fridolin! In terms of CRUD endpoints, I wonder how it would work for end users... looking at https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=17428, the messages seem a bit strange to me. { error => "Something went wrong, check the logs." }, 500 ); That might make sense if it's just Koha consuming Koha services, but what about third-parties? I imagine it more like the Spotify API: https://developer.spotify.com/web-api/get-album/ https://developer.spotify.com/web-api/user-guide/#response-status-codes https://developer.spotify.com/web-api/user-guide/#error-details You return the HTTP code and then you have a standard format for details. With a 500 error, I don't think you'd actually send a message, since you don't really have anything to say, since it's an internal server error. Actually, I'm not sure about the use of 500 for DBIx::Class::Exception... but I haven't looked into our use of that exception yet. If you've provided a bad value or a bad field, maybe it would make more sense to return 400 for a bad request rather than saying there was an internal server error which tend to arise unexpectedly. Bad values or bad fields are somewhat predictable. Anyway, I'm just curious about whatever conventions we use, so that I can apply them consistently in whatever code I (and others) contribute. David Cook Systems Librarian Prosentient Systems 72/330 Wattle St Ultimo, NSW 2007 Australia Office: 02 9212 0899 Direct: 02 8005 0595
-----Original Message----- From: koha-devel-bounces@lists.koha-community.org [mailto:koha-devel- bounces@lists.koha-community.org] On Behalf Of Fridolin SOMERS Sent: Wednesday, 12 October 2016 6:32 PM To: koha-devel@lists.koha-community.org Subject: Re: [Koha-devel] Marseille16 / REST api
Here are my notes : https://wiki.koha- community.org/wiki/Marseille_hackfest_2016#REST_API_-_Thomas
El mié., 12 oct. 2016 a las 7:26, David Cook (<dcook@prosentient.com.au>) escribió:
Really curious to see how this plays out!
I’ve just added parameter validation to a Koha::Object, and while it works well enough, I’m hoping for a more generalized solution. I haven’t looked at Koha::Exceptions::* yet, but maybe that will help.
I don't know how that would work, what bug number is it?
Peeking at Koha::Exceptions::MissingParameter, I hope that there’s more specificity than just “A required parameter is missing”. I’d want to know which required parameter is missing.
Is there a document somewhere saying how to use Koha::Exceptions?
Well, we are not baking our own exception system, we are just using Class::Exception so it is pretty documented!
Look at bug 17425, you will notice when we throw an exception we can add a message.
Regards!
David Cook
Systems Librarian
Prosentient Systems
72/330 Wattle St
Ultimo, NSW 2007
Australia
Office: 02 9212 0899 <02%2092%2012%2008%2099>
Direct: 02 8005 0595 <02%2080%2005%2005%2095>
*From:* koha-devel-bounces@lists.koha-community.org [mailto: koha-devel-bounces@lists.koha-community.org] *On Behalf Of *Tomas Cohen Arazi *Sent:* Wednesday, 12 October 2016 2:39 AM *To:* koha-devel <koha-devel@lists.koha-community.org> *Subject:* [Koha-devel] Marseille16 / REST api
During the first couple Hackfest days, Jonathan, Benjamin and I worked on a reference implementation of CRUD code for a REST endpoint, so others can read it, discuss it and use it as a reference for
Le 12/10/2016 à 09:17, Tomas Cohen Arazi a écrit : their own developments.
We worked on Koha::Cit(y|ies) because it was a really simple class. All our work is now on bug 17428.
The main goals/concepts we tried to apply were:
* Controller class (Koha::REST::V1::Cities) should be as simple as possible. No business logic on it. All business logic is expected to be put on the Koha::Cit(ies|y) classes. And fully tested.
* All verbs/use cases should be covered by tests (t/db_dependent/api/v1/cities.t). We did it, and this file could be used (with little adjustments) as the basis for new endpoint tests.
* Heavy use of exceptions. I wouldn't say we heavily use them, but the point is that we pass everything to the business object, and catch exceptions it might raise. Martin pointed out that he would help us further simplify it, making heavier use of the Swagger plugin's
facilities.
Specially on parameters sanity check. More on this tomorrow!
* Koha::Exceptions got per-class files so the exceptions file is more manageable. Bug 17425 introduced Koha/Exceptions/Object.pm, and we propose that's the way to go (Koha/Exceptions.pm still has Virtualshelves-related exceptions that should be moved).
* Make use of Try::Tiny for try/catch blocks. On the process we wrote bug 17425, which introduces new exceptions, we added the dependency for Try::Tiny (no worries, it is packaged for Jessie/Ubuntu) and Mirko was here to validate.
* Moving business-logic to Koha:: namespace and write REST endpoints on top of that business objects. We picked a simple object, Koha::Patron(s) will be a more complex one of course. This is what Jonathan has been doing, and people willing to write REST endpoints should check with him, and probably help moving business logic into Koha:: namespace.
There are several patches on bugzilla introducing endpoints. We will try to contact patch authors to help them make their work match this proposed 'guidelines'.
We are sticking to the 'patches speak' approach, so feel free to criticize this implementation, to improve it or even provide a counter-proposal. We are otherwise moving on, trying to get a functional complete REST api ASAP.
Thanks!
Tomas, Jonathan, Benjamin
--
Tomás Cohen Arazi
Theke Solutions (https://theke.io <http://theke.io/>) ✆ +54 9351 3513384 <+54%209%20351%20351-3384> GPG: B2F3C15F
_______________________________________________ Koha-devel mailing list Koha-devel@lists.koha-community.org http://lists.koha-community.org/cgi-bin/mailman/listinfo/koha-devel website : http://www.koha-community.org/ git : http://git.koha-community.org/ bugs : http://bugs.koha-community.org/
-- Fridolin SOMERS Biblibre - Pôles support et système fridolin.somers@biblibre.com _______________________________________________ Koha-devel mailing list Koha-devel@lists.koha-community.org http://lists.koha-community.org/cgi-bin/mailman/listinfo/koha-devel website : http://www.koha-community.org/ git : http://git.koha- community.org/ bugs : http://bugs.koha-community.org/
The code you highlighted comes from the unit tests. That's why it seems too generic. If you look at the actual controller class code, you will notice we are catching several kinds of exceptions and doing what needs to be done on each. But we still have the possibility that another exception we didn't consider reached the controller, hence the 'Something went wrong, see the logs' generic message. It's a catch-all fallback. Regarding the error codes, we have followed what seemed the regular use in bibliography, which is of course subject to discussion/improvement. But keep in mind that it is mostly bad formed data, or non existing fields attempted to be updated/created, so I think the 500 is a good idea. What error you think would suit better? BTW, Martin highlighted yesterday that we could make heavier use of swagger for parameters validation, so in theory we should not hit the controller script (not to speak of dbix) if parameters are wrong. I have the feeling we shouldn't, because the trade off in terms of bureaucracy on writing json files is quite negative. Anyway, I still think it makes a whole lot of sense that we raise an exception on Koha::Objects if dbix would die due to bad parameters, don't you think? El jue., 13 de oct. de 2016 2:08 AM, David Cook <dcook@prosentient.com.au> escribió:
Cheers, Fridolin!
In terms of CRUD endpoints, I wonder how it would work for end users... looking at https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=17428, the messages seem a bit strange to me.
{ error => "Something went wrong, check the logs." }, 500 );
That might make sense if it's just Koha consuming Koha services, but what about third-parties?
I imagine it more like the Spotify API: https://developer.spotify.com/web-api/get-album/ https://developer.spotify.com/web-api/user-guide/#response-status-codes https://developer.spotify.com/web-api/user-guide/#error-details
You return the HTTP code and then you have a standard format for details. With a 500 error, I don't think you'd actually send a message, since you don't really have anything to say, since it's an internal server error.
Actually, I'm not sure about the use of 500 for DBIx::Class::Exception... but I haven't looked into our use of that exception yet. If you've provided a bad value or a bad field, maybe it would make more sense to return 400 for a bad request rather than saying there was an internal server error which tend to arise unexpectedly. Bad values or bad fields are somewhat predictable.
Anyway, I'm just curious about whatever conventions we use, so that I can apply them consistently in whatever code I (and others) contribute.
David Cook Systems Librarian Prosentient Systems 72/330 Wattle St Ultimo, NSW 2007 Australia
Office: 02 9212 0899 Direct: 02 8005 0595
-----Original Message----- From: koha-devel-bounces@lists.koha-community.org [mailto:koha-devel- bounces@lists.koha-community.org] On Behalf Of Fridolin SOMERS Sent: Wednesday, 12 October 2016 6:32 PM To: koha-devel@lists.koha-community.org Subject: Re: [Koha-devel] Marseille16 / REST api
Here are my notes : https://wiki.koha- community.org/wiki/Marseille_hackfest_2016#REST_API_-_Thomas
El mié., 12 oct. 2016 a las 7:26, David Cook (<dcook@prosentient.com.au>) escribió:
Really curious to see how this plays out!
I’ve just added parameter validation to a Koha::Object, and while it works well enough, I’m hoping for a more generalized solution. I haven’t looked at Koha::Exceptions::* yet, but maybe that will help.
I don't know how that would work, what bug number is it?
Peeking at Koha::Exceptions::MissingParameter, I hope that there’s more specificity than just “A required parameter is missing”. I’d want to know which required parameter is missing.
Is there a document somewhere saying how to use Koha::Exceptions?
Well, we are not baking our own exception system, we are just using Class::Exception so it is pretty documented!
Look at bug 17425, you will notice when we throw an exception we can add a message.
Regards!
David Cook
Systems Librarian
Prosentient Systems
72/330 Wattle St
Ultimo, NSW 2007
Australia
Office: 02 9212 0899 <02%2092%2012%2008%2099>
Direct: 02 8005 0595 <02%2080%2005%2005%2095>
*From:* koha-devel-bounces@lists.koha-community.org [mailto: koha-devel-bounces@lists.koha-community.org] *On Behalf Of *Tomas Cohen Arazi *Sent:* Wednesday, 12 October 2016 2:39 AM *To:* koha-devel <koha-devel@lists.koha-community.org> *Subject:* [Koha-devel] Marseille16 / REST api
During the first couple Hackfest days, Jonathan, Benjamin and I worked on a reference implementation of CRUD code for a REST endpoint, so others can read it, discuss it and use it as a reference
for
We worked on Koha::Cit(y|ies) because it was a really simple class. All our work is now on bug 17428.
The main goals/concepts we tried to apply were:
* Controller class (Koha::REST::V1::Cities) should be as simple as possible. No business logic on it. All business logic is expected to be put on the Koha::Cit(ies|y) classes. And fully tested.
* All verbs/use cases should be covered by tests (t/db_dependent/api/v1/cities.t). We did it, and this file could be used (with little adjustments) as the basis for new endpoint tests.
* Heavy use of exceptions. I wouldn't say we heavily use them, but the point is that we pass everything to the business object, and catch exceptions it might raise. Martin pointed out that he would help us further simplify it, making heavier use of the Swagger
Le 12/10/2016 à 09:17, Tomas Cohen Arazi a écrit : their own developments. plugin's facilities.
Specially on parameters sanity check. More on this tomorrow!
* Koha::Exceptions got per-class files so the exceptions file is more manageable. Bug 17425 introduced Koha/Exceptions/Object.pm, and we propose that's the way to go (Koha/Exceptions.pm still has Virtualshelves-related exceptions that should be moved).
* Make use of Try::Tiny for try/catch blocks. On the process we wrote bug 17425, which introduces new exceptions, we added the dependency for Try::Tiny (no worries, it is packaged for Jessie/Ubuntu) and Mirko was here to validate.
* Moving business-logic to Koha:: namespace and write REST endpoints on top of that business objects. We picked a simple object, Koha::Patron(s) will be a more complex one of course. This is what Jonathan has been doing, and people willing to write REST endpoints should check with him, and probably help moving business logic into Koha:: namespace.
There are several patches on bugzilla introducing endpoints. We will try to contact patch authors to help them make their work match this proposed 'guidelines'.
We are sticking to the 'patches speak' approach, so feel free to criticize this implementation, to improve it or even provide a counter-proposal. We are otherwise moving on, trying to get a functional complete REST api ASAP.
Thanks!
Tomas, Jonathan, Benjamin
--
Tomás Cohen Arazi
Theke Solutions (https://theke.io <http://theke.io/>) ✆ +54 9351 3513384 <+54%209%20351%20351-3384> GPG: B2F3C15F
_______________________________________________ Koha-devel mailing list Koha-devel@lists.koha-community.org http://lists.koha-community.org/cgi-bin/mailman/listinfo/koha-devel website : http://www.koha-community.org/ git : http://git.koha-community.org/ bugs : http://bugs.koha-community.org/
-- Fridolin SOMERS Biblibre - Pôles support et système fridolin.somers@biblibre.com _______________________________________________ Koha-devel mailing list Koha-devel@lists.koha-community.org http://lists.koha-community.org/cgi-bin/mailman/listinfo/koha-devel website : http://www.koha-community.org/ git : http://git.koha- community.org/ bugs : http://bugs.koha-community.org/
-- Tomás Cohen Arazi Theke Solutions (https://theke.io <http://theke.io/>) ✆ +54 9351 3513384 GPG: B2F3C15F
Hi Tomas, It’s bug 10662, but I haven’t posted the revised patches with the parameter validation yet. After reviewing bug 17425 and the documentation for Class::Exception, I see what you’re saying. These two sections are the part that explain it for me best: <http://search.cpan.org/~drolsky/Exception-Class-1.40/lib/Exception/Class/Base.pm#MyException->throw(_$message_)> http://search.cpan.org/~drolsky/Exception-Class-1.40/lib/Exception/Class/Base.pm#MyException->throw(_$message_) <http://search.cpan.org/~drolsky/Exception-Class-1.40/lib/Exception/Class/Base.pm#$exception->message()> http://search.cpan.org/~drolsky/Exception-Class-1.40/lib/Exception/Class/Base.pm#$exception->message() However, I think there’s still room for convention. For instance: try { $patron->blah('blah'); } catch { ok( $_->isa('Koha::Exceptions::Object::MethodNotFound'), 'Calling a non-existent method should raise a Koha::Exceptions::Object::MethodNotFound exception' ); }; This is a basic example… I’d want to see “which” method was not found. Of course, Object.pm defines that in the exception: Koha::Exceptions::Object::MethodNotFound->throw( "No method $method for " . ref($self) ); Koha::Exceptions::Object::PropertyNotFound->throw( "No property $p for " . ref($self) ); However, that’s more human readable than machine readable. Let’s say we’re doing a CRUD form for the web UI, and we have something like Koha::Exceptions::Object::ValueInvalid. I think we’d want an error code or error message that would be easy to catch in the code, and then we relay that to the template in a way which allows for translation. In my code, I’ve been doing it like in my .pm/.pl: $errors->{url}->{invalid_scheme} = 1; Then in the template: [% IF ( errors.url.invalid_scheme ) %] Your url must start with http:// or https:// [% END %] While my approach works, I don’t know that I’ve seen it elsewhere in Koha, and it just feels a bit… suboptimal to me. I don’t know why. I suppose if I were using exceptions… it might be something like Koha::Exceptions::URI::InvalidScheme, and I’d probably be manually throwing that error in my processing of the CRUD form (since different forms might accept URIs with different schemes). I suppose in this case I don’t necessarily need the URI scheme that they did use… I just need to tell them the one that they “need to use” and I know that based on my controller’s logic and display it with the view. I suppose if they did use a scheme like “ftp”, I would know about it since I’m trying to catch that exception… and then pass it to the view if necessary. So I guess in the end my questions are a bit irrelevant in terms of exceptions per se and relate to how we surface errors for users in a consistent way… David Cook Systems Librarian Prosentient Systems 72/330 Wattle St Ultimo, NSW 2007 Australia Office: 02 9212 0899 Direct: 02 8005 0595 From: Tomas Cohen Arazi [mailto:tomascohen@gmail.com] Sent: Wednesday, 12 October 2016 6:17 PM To: David Cook <dcook@prosentient.com.au>; koha-devel <koha-devel@lists.koha-community.org> Subject: Re: [Koha-devel] Marseille16 / REST api El mié., 12 oct. 2016 a las 7:26, David Cook (<dcook@prosentient.com.au <mailto:dcook@prosentient.com.au> >) escribió: Really curious to see how this plays out! I’ve just added parameter validation to a Koha::Object, and while it works well enough, I’m hoping for a more generalized solution. I haven’t looked at Koha::Exceptions::* yet, but maybe that will help. I don't know how that would work, what bug number is it? Peeking at Koha::Exceptions::MissingParameter, I hope that there’s more specificity than just “A required parameter is missing”. I’d want to know which required parameter is missing. Is there a document somewhere saying how to use Koha::Exceptions? Well, we are not baking our own exception system, we are just using Class::Exception so it is pretty documented! Look at bug 17425, you will notice when we throw an exception we can add a message. Regards! David Cook Systems Librarian Prosentient Systems 72/330 Wattle St Ultimo, NSW 2007 Australia Office: 02 9212 0899 <tel:02%2092%2012%2008%2099> Direct: 02 8005 0595 <tel:02%2080%2005%2005%2095> From: koha-devel-bounces@lists.koha-community.org <mailto:koha-devel-bounces@lists.koha-community.org> [mailto:koha-devel-bounces@lists.koha-community.org <mailto:koha-devel-bounces@lists.koha-community.org> ] On Behalf Of Tomas Cohen Arazi Sent: Wednesday, 12 October 2016 2:39 AM To: koha-devel <koha-devel@lists.koha-community.org <mailto:koha-devel@lists.koha-community.org> > Subject: [Koha-devel] Marseille16 / REST api During the first couple Hackfest days, Jonathan, Benjamin and I worked on a reference implementation of CRUD code for a REST endpoint, so others can read it, discuss it and use it as a reference for their own developments. We worked on Koha::Cit(y|ies) because it was a really simple class. All our work is now on bug 17428. The main goals/concepts we tried to apply were: * Controller class (Koha::REST::V1::Cities) should be as simple as possible. No business logic on it. All business logic is expected to be put on the Koha::Cit(ies|y) classes. And fully tested. * All verbs/use cases should be covered by tests (t/db_dependent/api/v1/cities.t). We did it, and this file could be used (with little adjustments) as the basis for new endpoint tests. * Heavy use of exceptions. I wouldn't say we heavily use them, but the point is that we pass everything to the business object, and catch exceptions it might raise. Martin pointed out that he would help us further simplify it, making heavier use of the Swagger plugin's facilities. Specially on parameters sanity check. More on this tomorrow! * Koha::Exceptions got per-class files so the exceptions file is more manageable. Bug 17425 introduced Koha/Exceptions/Object.pm, and we propose that's the way to go (Koha/Exceptions.pm still has Virtualshelves-related exceptions that should be moved). * Make use of Try::Tiny for try/catch blocks. On the process we wrote bug 17425, which introduces new exceptions, we added the dependency for Try::Tiny (no worries, it is packaged for Jessie/Ubuntu) and Mirko was here to validate. * Moving business-logic to Koha:: namespace and write REST endpoints on top of that business objects. We picked a simple object, Koha::Patron(s) will be a more complex one of course. This is what Jonathan has been doing, and people willing to write REST endpoints should check with him, and probably help moving business logic into Koha:: namespace. There are several patches on bugzilla introducing endpoints. We will try to contact patch authors to help them make their work match this proposed 'guidelines'. We are sticking to the 'patches speak' approach, so feel free to criticize this implementation, to improve it or even provide a counter-proposal. We are otherwise moving on, trying to get a functional complete REST api ASAP. Thanks! Tomas, Jonathan, Benjamin -- Tomás Cohen Arazi Theke Solutions (https://theke.io <http://theke.io/> ) ✆ +54 9351 3513384 <tel:+54%209%20351%20351-3384> GPG: B2F3C15F -- Tomás Cohen Arazi Theke Solutions (https://theke.io <http://theke.io/> ) ✆ +54 9351 3513384 GPG: B2F3C15F
I didn't find you on IRC to talk about it, so I'll do it here. El jue., 13 oct. 2016 a las 1:52, David Cook (<dcook@prosentient.com.au>) escribió:
However, that’s more human readable than machine readable. Let’s say we’re doing a CRUD form for the web UI, and we have something like Koha::Exceptions::Object::ValueInvalid. I think we’d want an error code or error message that would be easy to catch in the code, and then we relay that to the template in a way which allows for translation.
You should look at Jonathan's work on Koha::Virtualshel(f|ves) classes, and how exceptions are handled in (say) shelves.pl because it will be enlightning on what we were thinking of. It of course covers all your questions, because that's what we were thinking of. By the time he wrote that, there was no opinion on Try::Tiny, so he uses eval, but he propagates the exception information up to the template file as you suggest you would need to do on your work. -- Tomás Cohen Arazi Theke Solutions (https://theke.io <http://theke.io/>) ✆ +54 9351 3513384 GPG: B2F3C15F
participants (3)
-
David Cook -
Fridolin SOMERS -
Tomas Cohen Arazi