This are the many ways to request

kearean_soap_api.go

const SOAPRequest = `<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://www.w3.org/2003/05/soap-envelope"
 xmlns:xsd="http://www.w3.org/2001/XMLSchema"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
 xmlns:base_services="http://wsdl.cybozu.co.jp/base/2008">
 <SOAP-ENV:Header>
  <Action SOAP-ENV:mustUnderstand="1" xmlns="http://schemas.xmlsoap.org/ws/2003/03/addressing">{{.Action}}</Action>
  <Security xmlns:wsu="http://schemas.xmlsoap.org/ws/2002/07/utility"
   SOAP-ENV:mustUnderstand="1"
   xmlns="http://schemas.xmlsoap.org/ws/2002/12/secext">
   <UsernameToken wsu:Id="id"><Username>{{.Username}}</Username><Password>{{.Password}}</Password></UsernameToken>
  </Security>
  <Timestamp SOAP-ENV:mustUnderstand="1" Id="id"
   xmlns="http://schemas.xmlsoap.org/ws/2002/07/utility">
   <Created>2037-08-12T14:45:00Z</Created>
   <Expires>2037-08-12T14:45:00Z</Expires>
  </Timestamp>
  <Locale>jp</Locale>
  </SOAP-ENV:Header><SOAP-ENV:Body>
  <{{.Action}}>
  {{.Parameters}}
 </{{.Action}}>
</SOAP-ENV:Body></SOAP-ENV:Envelope>
`

type APIParameters struct {
        Username, Password, Action, Parameters string
}




func main() {
        var api_parameters = APIParameters{"ID", "パスワード", "ScheduleGetEvents", `<parameters start="2014-01-01T08:00:00" end="2014-01-30T20:00:00" ></parameters>`}
        var url = "https://ほげほげほげ/grn.cgi/cbpapi/schedule/api?"

        //リクエストbodyのテンプレートを適用
        t := template.Must(template.New("SOAPRequest").Parse(SOAPRequest))
        body := bytes.NewBufferString("")
        err := t.Execute(body, api_parameters)
        if err != nil {
                log.Panicf("template.Execute: %#v", err)
        }

        // Postする
        response, err := http.Post(url, "text/xml; charset=utf-8", body)
        if err != nil {
                log.Panicf("http.Post: %#v", err)
        }

        //レスポンスを読み込んで表示
        b, err := ioutil.ReadAll(response.Body)
        response.Body.Close()
        if err != nil {
                log.Panicf("ioutil.ReadAll: %#v", err)
        }
        fmt.Printf(string(b))
        return
}

request_soap.xml

<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://www.w3.org/2003/05/soap-envelope"
 xmlns:xsd="http://www.w3.org/2001/XMLSchema"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
 xmlns:base_services="http://wsdl.cybozu.co.jp/base/2008">
  <SOAP-ENV:Header>
    <Action SOAP-ENV:mustUnderstand="1"
     xmlns="http://schemas.xmlsoap.org/ws/2003/03/addressing">
      ScheduleGetEvents
    </Action>
    <Security xmlns:wsu="http://schemas.xmlsoap.org/ws/2002/07/utility"
     SOAP-ENV:mustUnderstand="1"
     xmlns="http://schemas.xmlsoap.org/ws/2002/12/secext">
      <UsernameToken wsu:Id="id">
        <Username>xxxxxxxxxx</Username>
        <Password>xxxxxxxxxx</Password>
      </UsernameToken>
    </Security>
    <Timestamp SOAP-ENV:mustUnderstand="1" Id="id"
     xmlns="http://schemas.xmlsoap.org/ws/2002/07/utility">
      <Created>2037-08-12T14:45:00Z</Created>
      <Expires>2037-08-12T14:45:00Z</Expires>
    </Timestamp>
    <Locale>jp</Locale>
  </SOAP-ENV:Header>
  <SOAP-ENV:Body>
    <ScheduleGetEvents>
<parameters start="2014-01-01T08:00:00" end="2014-01-30T20:00:00" > 
</parameters>
    </ScheduleGetEvents>
  </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

response_soap.xml

<?xml version="1.0" encoding="utf-8" ?>
 <soap:Envelope>
 <soap:Header>
<vendor>Cybozu</vendor>
<product>Garoon</product>
<product_type>1</product_type>
<version>3.7.2</version>
<apiversion>1.3.0</apiversion>
 </soap:Header>
<soap:Body>
<schedule:ScheduleGetEventsResponse>
<returns>
<schedule_event id="3451422" event_type="repeat" public_type="public" plan="打合せ" ・・・・
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