Query / Create / Update / Delete data in the repository with GraphQL

[oguimard]

The REST API based on GraphQL allows to perform all actions of the CRUD :

• Create
• Read
• Update
• Delete

This mechanism allows to perform a various kind of action into the repository. Read action are performed with the keyword "query" in GraphQL whereas Read/Update/Delete are performed with the "mutation" keyword.

All the example below are performed with the ITPM schema.

Basics queries

Get an object with it's attributes

• For instance the following query will return the name of the applications

Query	Result
query app { application { name } }	{ "data": { "application": [ { "name": "AA" }, { "name": "Account Management" } ] } }

Get an object with it's relations

• For instance the following query will return the applications and their related business process

Query	Result
query { application { id name businessProcess { id name } } }	{ "data": { "application": [ { "id": "snf5hRn0U91K", "name": "AA", "businessProcess": [] }, { "id": "IubjeRlyFfT1", "name": "Account Management", "businessProcess": [ { "id": "12qog2pV99fG", "name": "Financial Reporting" } ] },

Basics mutations

Create an object

• For instance the following mutation will create a new application. If creation is successful the result returned the created object.

Query	Result
mutation { createApplication(application:{ name:"new application" }) { id name } }	{ "data": { "createApplication": { "id": "x2wrAYDkWP8H", "name": "new application" } } }

Create an object with a relationship

• For instance the following mutation will create a new application and link it to an existing business process. If creation is successful the result returned the created object.

Query	Result
mutation { createApplication(application : { name: "new app 3" businessProcess: { action:ADD list:[{id:"39cXIxu2HHrI"}] } }) { id name businessProcess { id name } } }	{ "data": { "createApplication": { "id": "Q2wradDkWbGH", "name": "new app 3", "businessProcess": [ { "id": "39cXIxu2HHrI", "name": "Accounting" } ] } } }

Updating an object

• For instance the following mutation will update an existing application. If update is successful the result returned the updated object.

Query	Result
mutation { updateApplication(id:"IubjeRlyFfT1" application:{ cloudComputing:Cloud_IaaS }) { id cloudComputing } }	{ "data": { "updateApplication": { "id": "IubjeRlyFfT1", "cloudComputing": "Cloud_IaaS" } } }

Delete an object

• For instance the following mutation will delete an existing application. If delete is successful the result returned the number of deleted object.

Query	Result
mutation { deleteApplication (id:"snf5hRn0U91K" cascade:false) { deletedCount } }	{ "data": { "deleteApplication": { "deletedCount": 1 } } }

 

[VieJay]

So far so fine, but how I update for example the creator of an application? This way don't work. It tells creator is not field at application, but if I query applications, I see creator is null or has an object with id, name and other. So how does it work?

[psalinas]

I need to change a field but in Spanish and with graphql it only changes it in English.
I saw a parameter in the x-hopex-language-data-id header, but I don't get it to work.

[oguimard]

Hello Hendrik,

As the name are not always unique we cannot use them as a mean to connect 2 objects. That's why we use ID.

You have 3 ways to connect :

• internal ID : for existing object that you already know the object
• external ID : for object that you create and that you have chosen to give an ID to make this type of connection. The ID will be store in the repository
• temporary ID : same as external ID but won't be store in the repository. this ID cannot be use for future use

[engeh]

Hello

Thank you for the article. 

Is it possible when updating or creating an object with a relationship. To search for example an object with the list not trough an id? for example: 

      list:[{name:"qwertz"}]

Instead of:

      list:[{id:"39cXIxu2HHrI"}]

This would be useful for an interface, because it's not always possible for an external to know the ID of the object in MEGA.

Kind regards

Hendrik