MicrosoftTeams Webhookの要求内容

#背景
社内のChatシステムが、ChatworkからMicrosoftTeamsに変更になる予定なので、
Webhookを使った各種ツールの移行が必要。
取り急ぎ、Webhookで何が通知されるのかを調べた。

```Request.json
{
    "method": "POST",
    "url": "https://xxxx.azurewebsites.net/api/xxxx",
    "originalUrl": "https://xxxx.azurewebsites.net/api/xxxx",
    "headers": {
        "accept": "application/json",
        "authorization": "HMAC xxxx",
        "connection": "Keep-Alive",
        "content-length": "1702",
        "content-type": "application/json; charset=utf-8",
        "expect": "100-continue",
        "host": "xxxx.azurewebsites.net",
        "max-forwards": "9",
        "referer": "https://teams.microsoft.com/",
        "x-ms-session-id": "Legacy-Operation-Id-xxxx",
        "x-ms-request-id": "xxxx",
        "x-waws-unencoded-url": "/api/xxxx",
        "client-ip": "10.0.32.4:52027",
        "x-arr-log-id": "xxxx",
        "x-site-deployment-id": "xxxx",
        "was-default-hostname": "xxxx.azurewebsites.net",
        "x-original-url": "/api/xxxx",
        "x-forwarded-for": "xxx.xxx.xxx.xxx:6144",
        "x-arr-ssl": "2048|256|C=US, O=Microsoft Corporation, CN=Microsoft RSA TLS CA 01|CN=*.azurewebsites.net",
        "x-forwarded-proto": "https",
        "x-appservice-proto": "https",
        "x-forwarded-tlsversion": "1.2",
        "disguised-host": "xxxx.azurewebsites.net"
    },
    "query": {
        "code": "xxxx"
    },
    "params": {},
    "body": {
        "type": "message",
        "id": "162390053xxxx",
        "timestamp": "2021-06-17T03:28:58.2669262Z",
        "localTimestamp": "2021-06-17T12:28:58.2669262+09:00",
        "serviceUrl": "https://smba.trafficmanager.net/apac/",
        "channelId": "msteams",
        "from": {
            "id": "xxxx(AzureADの送信者IDか？)",
            "name": "xxxx（送信者の名前）",
            "aadObjectId": "xxxx"
        },
        "conversation": {
            "isGroup": true,
            "id": "xxxx（チームのIDか？）@thread.tacv2;messageid=162390004xxxx",
            "name": null,
            "conversationType": "channel",
            "tenantId": "xxxx"
        },
        "recipient": null,
        "textFormat": "plain",
        "attachmentLayout": null,
        "membersAdded": [],
        "membersRemoved": [],
        "topicName": null,
        "historyDisclosed": null,
        "locale": "ja-JP",
        "text": "<at>myFirstWebhook（Webhook名）</at>&nbsp;Hello, dump message.\n",
        "speak": null,
        "inputHint": null,
        "summary": null,
        "suggestedActions": null,
        "attachments": [
            {
                "contentType": "text/html",
                "contentUrl": null,
                "content": "<div><div><span itemscope=\"\" itemtype=\"http://schema.skype.com/Mention\" itemid=\"0\">myFirstWebhook</span>&nbsp;Hello, dump message.</div>\n</div>",
                "name": null,
                "thumbnailUrl": null
            }
        ],
        "entities": [
            {
                "type": "clientInfo",
                "locale": "ja-JP",
                "country": "JP",
                "platform": "Mac",
                "timezone": "Asia/Tokyo"
            }
        ],
        "channelData": {
            "teamsChannelId": "xxxx",
            "teamsTeamId": "xxxx",
            "channel": {
                "id": "xxxx"
            },
            "team": {
                "id": "xxxx"
            },
            "tenant": {
                "id": "xxxx"
            }
        },
        "action": null,
        "replyToId": null,
        "value": null,
        "name": null,
        "relatesTo": null,
        "code": null,
        "localTimezone": "Asia/Tokyo"
    },
    "rawBody": "...上と同じ..."
}


```

Outgoing Webhook
https://docs.microsoft.com/en-us/microsoftteams/platform/webhooks-and-connectors/how-to/add-outgoing-webhook

Incoming Webhook
https://docs.microsoft.com/en-us/microsoftteams/platform/webhooks-and-connectors/how-to/add-incoming-webhook