Stap 1. Postman OAuth2 Token Request
- Grant Type: Authorization Code
- Callback URL: http://example.com/oauth2callback
- Token URL: https://accounts.google.com/o/oauth2/auth
- Access Token URL: https://accounts.google.com/o/oauth2/token
- Client ID: *****
- Client Secret: *****
- Scope: email https://www.googleapis.com/auth/calendar
- Client Authentication: Send as Basic Auth header

Result:

Token Name
Google
Access Token
ya29.GlvUBZp3DxXVpGQizr692dniRLdmbQFvcHHtIzSkZO6QbsWzH-bNLOzkLZfnFRi-WVlyTWP0reasrHErPEutQQYRHFRT519RMeir1DAYvyLu4M25W9L_xMKX9AKE
Token Type
Bearer
expires_in
3599
id_token
eyJhbGciOiJSUzI1NiIsImtpZCI6IjE5MjMzOTczODFkOTU3NGJiODczMjAyYTkwYzMyYjdjZWVhZWQwMjcifQ.eyJhenAiOiIzMTIyNjYyMDEwMjktbmlwbmV2cHFibzhoMDJiNzRuMjFtOXRiZ2o3cjg3dGguYXBwcy5nb29nbGV1c2VyY29udGVudC5jb20iLCJhdWQiOiIzMTIyNjYyMDEwMjktbmlwbmV2cHFibzhoMDJiNzRuMjFtOXRiZ2o3cjg3dGguYXBwcy5nb29nbGV1c2VyY29udGVudC5jb20iLCJzdWIiOiIxMTU3OTY3NjQ2ODE4MjM4Njk0NjUiLCJlbWFpbCI6ImRyay5hbmFzczEyQGdtYWlsLmNvbSIsImVtYWlsX3ZlcmlmaWVkIjp0cnVlLCJhdF9oYXNoIjoia3FxVWNKM09HRVFzXzl0UF91OTJrUSIsImV4cCI6MTUyODQ3Nzg5OCwiaXNzIjoiYWNjb3VudHMuZ29vZ2xlLmNvbSIsImlhdCI6MTUyODQ3NDI5OH0.ShvgYCtxjd09kFFO5WjQh8pnMeoSzpdpg2DbWMpsvpFyeHrvH3qsuR6i77R8Tc64bspbnD2J53phBvEuLFcK1J9Ho6OpWzAe7js9IiRJWzf-STG6S0yfJIV4hcUy1RcOB-9tQ22dyXp1hlDXFBpwaJNE5iaVN6x_XsW44Qb6zjA66tzPFy7zWsUK2pwI1DmQyMQbNa8xm21CohsqkMaLFe67TbMpr_ae_6_h5TvlYSOLUtxLdwo7bqOhFdq_6CIaSHyDcC_83DFAc8LnH9Cvuz1AQJk6QxT81A7IqF7hk6phFfQxxw1bAMWDNV_HtOgxdaWdF1QX6xJwBpzUH37rTw

Stap 2. Agenda's ophalen
- URL: https://www.googleapis.com/calendar/v3/users/me/calendarList
- Auth: Bearer *****

Result:
{
    "kind": "calendar#calendarList",
    "etag": "\"p33c9bg6rpajdm0g\"",
    "nextSyncToken": "CNiVwNvKptsCEhVkcmsuYW5hc3MxMkBnbWFpbC5jb20=",
    "items": [
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1506639216462000\"",
            "id": "mhffuem5u24kf7j2l52n4q8u6led0gv0@import.calendar.google.com",
            "summary": "Avans 42IN05sol",
            "description": "Avans Rooster voor 42IN05sol",
            "timeZone": "Europe/Amsterdam",
            "summaryOverride": "Avans 42IN05SOl",
            "colorId": "17",
            "backgroundColor": "#9a9cff",
            "foregroundColor": "#000000",
            "selected": true,
            "accessRole": "reader",
            "defaultReminders": [],
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        },
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1517013613174000\"",
            "id": "91t9phohoq4mrnspk9hn7gkj2rhqfg0c@import.calendar.google.com",
            "summary": "Avans 42IN08SOf",
            "description": "Avans Rooster voor 42IN08SOf",
            "timeZone": "Europe/Amsterdam",
            "colorId": "2",
            "backgroundColor": "#d06b64",
            "foregroundColor": "#000000",
            "selected": true,
            "accessRole": "reader",
            "defaultReminders": [],
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        },
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1511787956033000\"",
            "id": "8pn50fl4cej39glhgh1a64874vuj77eg@import.calendar.google.com",
            "summary": "Avans 42IN05sol",
            "description": "Avans Rooster voor 42IN05sol",
            "timeZone": "Europe/Amsterdam",
            "colorId": "9",
            "backgroundColor": "#7bd148",
            "foregroundColor": "#000000",
            "accessRole": "reader",
            "defaultReminders": [],
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        },
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1520100225548000\"",
            "id": "drk.anass12@gmail.com",
            "summary": "drk.anass12@gmail.com",
            "timeZone": "Europe/Amsterdam",
            "colorId": "15",
            "backgroundColor": "#9fc6e7",
            "foregroundColor": "#000000",
            "selected": true,
            "accessRole": "owner",
            "defaultReminders": [
                {
                    "method": "email",
                    "minutes": 10
                },
                {
                    "method": "popup",
                    "minutes": 30
                }
            ],
            "notificationSettings": {
                "notifications": [
                    {
                        "type": "eventCreation",
                        "method": "email"
                    },
                    {
                        "type": "eventChange",
                        "method": "email"
                    },
                    {
                        "type": "eventCancellation",
                        "method": "email"
                    },
                    {
                        "type": "eventResponse",
                        "method": "email"
                    }
                ]
            },
            "primary": true,
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        },
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1523830106097000\"",
            "id": "fbvc6pngn9dc9kvujhcgbuomh8hcin7f@import.calendar.google.com",
            "summary": "Avans 42IN12SOd",
            "description": "Avans Rooster voor 42IN12SOd",
            "timeZone": "Europe/Amsterdam",
            "colorId": "7",
            "backgroundColor": "#42d692",
            "foregroundColor": "#000000",
            "selected": true,
            "accessRole": "reader",
            "defaultReminders": [],
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        },
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1517013815429000\"",
            "id": "pv85j2i745brjtgojittrmjb3d7b91ar@import.calendar.google.com",
            "summary": "Avans 42IN11SOd",
            "description": "Avans Rooster voor 42IN11SOd",
            "timeZone": "Europe/Amsterdam",
            "colorId": "23",
            "backgroundColor": "#cd74e6",
            "foregroundColor": "#000000",
            "selected": true,
            "accessRole": "reader",
            "defaultReminders": [],
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        },
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1511626812480000\"",
            "id": "ot4ae8r2g4m1gmv346fg6ouarkbf4gmu@import.calendar.google.com",
            "summary": "Avans 42IN06SOl",
            "description": "Avans Rooster voor 42IN06SOl",
            "timeZone": "Europe/Amsterdam",
            "colorId": "18",
            "backgroundColor": "#b99aff",
            "foregroundColor": "#000000",
            "selected": true,
            "accessRole": "reader",
            "defaultReminders": [],
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        },
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1520100224639000\"",
            "id": "#contacts@group.v.calendar.google.com",
            "summary": "Contacts",
            "timeZone": "Europe/Amsterdam",
            "summaryOverride": "Contacts",
            "colorId": "17",
            "backgroundColor": "#9a9cff",
            "foregroundColor": "#000000",
            "accessRole": "reader",
            "defaultReminders": [],
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        },
        {
            "kind": "calendar#calendarListEntry",
            "etag": "\"1506639139917000\"",
            "id": "nl.dutch#holiday@group.v.calendar.google.com",
            "summary": "Feestdagen in Nederland",
            "timeZone": "Europe/Amsterdam",
            "summaryOverride": "Feestdagen in Nederland",
            "colorId": "7",
            "backgroundColor": "#42d692",
            "foregroundColor": "#000000",
            "selected": true,
            "accessRole": "reader",
            "defaultReminders": [],
            "conferenceProperties": {
                "allowedConferenceSolutionTypes": [
                    "eventHangout"
                ]
            }
        }
    ]
}

Stap 3. Agenda events ophalen met agenda id
URL: https://www.googleapis.com/calendar/v3/calendars/drk.anass12@gmail.com/events
Auth: Bearer ****

Result:
{
    "kind": "calendar#events",
    "etag": "\"p33c9bg6rpajdm0g\"",
    "summary": "drk.anass12@gmail.com",
    "updated": "2018-05-27T19:04:25.527Z",
    "timeZone": "Europe/Amsterdam",
    "accessRole": "owner",
    "defaultReminders": [
        {
            "method": "email",
            "minutes": 10
        },
        {
            "method": "popup",
            "minutes": 30
        }
    ],
    "nextSyncToken": "CNiVwNvKptsCENiVwNvKptsCGAU=",
    "items": ****
}