Salesforce REQUIRED_FIELD_MISSING, Required fields are missing: [Company_Make__c

Question

I am getting this error below when i tried testing my apex rest services using work bench

System.DmlException: Insert failed. First exception on row 0; first error: REQUIRED_FIELD_MISSING, Required fields are missing: [Company_Make__c, Engine_Displacement__c, Power__c, Torque__c, Transmission__c, Fuel_Tank_Capacity__c]: [Company_Make__c, Engine_Displacement__c, Power__c, Torque__c, Transmission__c, Fuel_Tank_Capacity__c] Class.BikeManagement.doPost: line 40, column 1

but iam passing all the required fields(cross checked with only layout i have).

my post method

@RestResource(urlMapping='/v1/BikeManagement/')
global class BikeManagement {
@httpPost
    global static bike__c doPost(){
        
        Map<String,String> urlParamsMap = RestContext.request.params;
        String bikename = urlParamsMap.get('Name');
        String cc= urlParamsMap.get('Engine_Displacement__c');
        String hp = urlParamsMap.get('Power__c');
        String Nm = urlParamsMap.get('Torque__c');
        String company = urlParamsMap.get('Company_Make__c');  
        String Gear = urlParamsMap.get('Transmission__c');
        String tank = urlParamsMap.get('Fuel_Tank_Capacity__c');
        bike__c postedbike =  new bike__c(Name=bikename,
                                          Engine_Displacement__c=cc,
                                          Power__c=hp,
                                          Torque__c=Nm,
                                          Company_Make__c=company,
                                          Transmission__c=Gear,
                                          Fuel_Tank_Capacity__c=tank);
        insert postedbike;                
        return postedbike;
    }
}

I have tried using below request data in rest explorer

Method -Post
URL - /services/apexrest/v1/BikeManagement/
body -
{
"Name":"Continental GT 650"
"Engine_Displacement__c":"648.9"
"Power__c":"47"
"Torque__c":"53"
"Company_Make__c":"Royal Enfield"
"Transmission__c":"6 Speed"
"Fuel_Tank_Capacity__c":"13"
}

Answer 1

RestContext.request.params are for Query String parameters (e.g. /services/apexrest/v1/BikeManagement?Name=Continental+GT+650&Engine_Displacement__c=648.9&...).

If you want to use your current design, you must set the Content-Type header to application/x-www-form-urlencoded and change the payload as follows:

Name=Continental+GT+650&Engine_Displacement__c=648.9&Power__c=47&Torque__c=53&Company_Make__c=Royal+Enfield&Transmission__c=6+Speed&Fuel_Tank_Capacity__c=13

Otherwise, if you want JSON, change your code to the following:

Map<String, String> urlParamsMap = (Map<String, Object>)JSON.deserializeUntyped(RestContext.request.getBody());

Note that you need to fix your JSON in that case (you're missing commas):

{
"Name":"Continental GT 650",
"Engine_Displacement__c":"648.9",
"Power__c":"47",
"Torque__c":"53",
"Company_Make__c":"Royal Enfield",
"Transmission__c":"6 Speed",
"Fuel_Tank_Capacity__c":"13"
}

Other alternatives are also possible, such as using:

{
    "request": {
        "bike": {
            "Name": "Continental GT 650",
            "Engine_Displacement__c": "648.9",
            "Power__c": "47",
            "Torque__c": "53",
            "Company_Make__c": "Royal Enfield",
            "Transmission__c": "6 Speed",
            "Fuel_Tank_Capacity__c": "13"
        }
    }
}

And changing your method signature to:

@httpPost
global static bike__c doPost(Bike__c bike){

This provides automatic deserialization for you, and supports XML and JSON without any modification to your code (I'd recommend this, personally).