Clear Values of Custom Fields

Optional. To be sure that the target issue field can have an empty value, send a GET request to the server:

curl -X GET \
'https://example.myjetbrains.com/youtrack/api/issues/2-7/customFields?fields=id,projectCustomField%28canBeEmpty,field%28name%29%29' \
-H 'Accept: application/json' \
-H 'Authorization: Bearer perm:am9obi5kb2U=.UG9zdG1hbiBKb2huIERvZQ==.jJe0eYhhkV271j1lCpfknNYOEakNk7' \
-H 'Content-Type: application/json' \
-H 'cache-control: no-cache'
                

To the sample request above, the server sends a response with the following body:

[
    {
        "projectCustomField": {
            "canBeEmpty": false,
            "field": {
                "name": "Priority",
                "$type": "CustomField"
            },
            "$type": "EnumProjectCustomField"
        },
        "id": "92-1",
        "$type": "SingleEnumIssueCustomField"
    },
    {
        "projectCustomField": {
            "canBeEmpty": false,
            "field": {
                "name": "Type",
                "$type": "CustomField"
            },
            "$type": "EnumProjectCustomField"
        },
        "id": "92-2",
        "$type": "SingleEnumIssueCustomField"
    },
    {
        "projectCustomField": {
            "canBeEmpty": false,
            "field": {
                "name": "State",
                "$type": "CustomField"
            },
            "$type": "StateProjectCustomField"
        },
        "id": "92-3",
        "$type": "StateIssueCustomField"
    },
    {
        "projectCustomField": {
            "canBeEmpty": true,
            "field": {
                "name": "Assignee",
                "$type": "CustomField"
            },
            "$type": "UserProjectCustomField"
        },
        "id": "94-0",
        "$type": "SingleUserIssueCustomField"
    },
    {
        "projectCustomField": {
            "canBeEmpty": true,
            "field": {
                "name": "Subsystem",
                "$type": "CustomField"
            },
            "$type": "OwnedProjectCustomField"
        },
        "id": "92-0",
        "$type": "SingleOwnedIssueCustomField"
    },
    {
        "projectCustomField": {
            "canBeEmpty": true,
            "field": {
                "name": "Fix versions",
                "$type": "CustomField"
            },
            "$type": "VersionProjectCustomField"
        },
        "id": "92-4",
        "$type": "MultiVersionIssueCustomField"
    },
    {
        "projectCustomField": {
            "canBeEmpty": true,
            "field": {
                "name": "Affected versions",
                "$type": "CustomField"
            },
            "$type": "VersionProjectCustomField"
        },
        "id": "92-5",
        "$type": "MultiVersionIssueCustomField"
    },
    {
        "projectCustomField": {
            "canBeEmpty": true,
            "field": {
                "name": "Fixed in build",
                "$type": "CustomField"
            },
            "$type": "BuildProjectCustomField"
        },
        "id": "92-6",
        "$type": "SingleBuildIssueCustomField"
    }
]
                

To clear the value of the Subsystem issue field, send a POST request as follows:

curl -X POST \
'https://example.myjetbrains.com/youtrack/api/issues/2-7?fields=customFields%28id,projectCustomField%28field%28name%29%29,value%28avatarUrl,buildLink,fullName,id,isResolved,login,minutes,name,presentation,text%29%29' \
-H 'Accept: application/json' \
-H 'Authorization: Bearer perm:am9obi5kb2U=.UG9zdG1hbiBKb2huIERvZQ==.jJe0eYhhkV271j1lCpfknNYOEakNk7' \
-H 'Content-Type: application/json' \
-H 'cache-control: no-cache' \
-d '{ "customFields": [ {"name":"Subsystem","$type":"SingleOwnedIssueCustomField","value":null} ] }'
                

To confirm that the target Subsystem field currently is set to an empty value, let's check the response from the server. For readability, we left only the target issue field in the response body sample:

{
    "customFields": [
        ...,
        {
            "projectCustomField": {
                "field": {
                    "name": "Subsystem",
                    "$type": "CustomField"
                },
                "$type": "OwnedProjectCustomField"
            },
            "value": null,
            "id": "92-0",
            "$type": "SingleOwnedIssueCustomField"
        },
        ...
    ],
    "$type": "Issue"
}
                

YouTrack Standalone 2020.3 Help

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