Update Issue Custom Fields

To update issue custom fields, send a POST request to the target issue. You can use either issue id or issues's entity id to reference issue.

POST /api/issues/{issueID}?[fields]

In the fields request parameter specify the attributes of the returned entity that you want to get in response. For example, id, name of an issue custom field and all attributes of its value. This will help to verify that your changes were applied.

In the request body specify the id or name, $type and value json for each issue custom field that you need to update.

To form value json you need to get id of the value (bundleElement) you want to post. For that:

Get corresponding Project Custom Field:
GET /api/admin/projects/{projectID}/customFields/{fieldID}
Get bundle from supported attributes for Project Custom Field:
GET /api/admin/projects/{projectID}/customFields/{fieldID}?fields=bundle(values(id,name,$type),aggregatedUsers(id,name,$type))

So, the final request is:

                    curl -X POST \
                    'https://example.myjetbrains.com/youtrack/api/issues/SP-8?fields=customFields(id,name,value(avatarUrl,buildLink,color(id),fullName,id,isResolved,localizedName,login,minutes,name,presentation,text))' \
                    -H 'Accept: application/json' \
                    -H 'Authorization: Bearer perm:am9obi5kb2U=.UG9zdG1hbiBKb2huIERvZQ==.jJe0eYhhkV271j1lCpfknNYOEakNk7' \
                    -H 'Content-Type: application/json' \
                    -d '{
                    "customFields": [
                    {"name":"Assignee","$type":"SingleUserIssueCustomField","value":{"login":"jane.doe"}},
                    {"name":"Priority","$type":"SingleEnumIssueCustomField","value":{"name":"Major"}},
                    {"name":"Fix versions","$type":"MultiVersionIssueCustomField","value":[{"name":"2019.1"}]},
                    {"name":"Requester email","$type":"SimpleIssueCustomField","value":"test@example.com"},
                    ] }'
                

To confirm that the target issue custom fields currently are set to corresponding values, let's check the response from the server:

                    {
                        "customFields":[
                            {
                                "id":"92-1",
                                "name":"Priority",
                                "value":{
                                    "localizedName":null,
                                    "color":{
                                        "id":"18"
                                    },
                                    "name":"Major",
                                    "id":"67-2"
                                }
                            },
                            ...
                            {
                                "id":"94-0",
                                "name":"Assignee",
                                "value":{
                                    "login":"jane.doe",
                                    "avatarUrl": "/hub/api/rest/avatar/90704ebe-c211-4906-a328-4f16ca82a5ea?s=48",
                                    "fullName":"Jane Doe",
                                    "name":"Jane Doe",
                                    "id":"1-3"
                                }
                            },
                            ...
                            {
                                "id":"92-4",
                                "name":"Fix versions",
                                "value":[
                                    {
                                        "id":"133-19",
                                        "name":"2019.1",
                                        "color":{
                                            "id":"3"
                                        }
                                    }
                                ]
                            }
                            ...
                            {
                                "id":"92-6",
                                "name":"Requester email",
                                "value":"test@example.com"
                            }
                            ...
                        ]
                    }
                

YouTrack Standalone 2019.3 Help

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