soql malformed in REST API on where clause for useremail

Question

while running this code in anonymous window getting the error below

        String useremailaddress = 'test@test.com';
        HttpRequest req = new HttpRequest();
        String query='SELECT+id+,+uuid__c+from+User+WHERE+Username='+useremailaddress;
        req.setEndpoint('callout:salesforceauthnam/services/data/v56.0/query?q='+query);
        req.setMethod('GET');
        Http http = new Http();
        HTTPResponse resp = http.send(req);
        system.debug('Body:'+resp.getBody());

Getting error malformed on where clause

[{"message":"\nuuid__c from User where Username= 'test@test.com'\n ^\nERROR at Row:1:Column:53\nBind variables only allowed in Apex code","errorCode":"MALFORMED_QUERY"}

Answer 1

As the error says you cannot use a Bind Variable in SOQL via REST API.

Try modifying the code as below

String query= = 'SELECT+id+,+uuid__c+from+User+WHERE+Username=\'' + String.escapeSingleQuotes(useremailaddress)+ '\'');

req.setEndpoint('callout:salesforceauthnam/services/data/v56.0/query?q='+query);

What I have done is instead of using the bind variable there, made sure to pass it as a normal string. I have used '\'' to escape the quotes. Also enclosed your username in escapeSingleQuotes to avoid SOQL Injection errors.