Coverity issue shows up after using pattern keyword for string data type #2941
Description
Problem statement
After using the pattern keyword for string data type, we can see Coverity issue on the go swagger generated code. It shows Explicit null dereferenced error in the operation files.
Swagger specification
Using pattern for the model parameters:
xyz:
user:
title: Username
description: Username
type: string
pattern: '^[^<>]+$'
required:
- user
Using the path below:
/update:
post:
consumes:
- application/json
parameters:
- in: body
name: xyz
schema:
type: object
$ref: '#/definitions/xyz'
responses:
200: # OK
schema:
type: string
400: # Bad Request
description: The parameters are incorrect
500: # Internal Error
description: Internal error
503: # Service Unavailable
description: Database unavailable
Coverity scans return the Explicit null dereferenced error on the operation file "post_update_parameters.go" (coverity errors are shown with """ ):
func (o *PostUpdateParams) BindRequest(r *http.Request, route *middleware.MatchedRoute) error {
var res []error
o.HTTPRequest = r
if runtime.HasBody(r) {
defer r.Body.Close()
"""
assign_null Assigning: body.User = nil.
"""
var body models.Xyz
if err := route.Consumer.Consume(r.Body, &body); err != nil {
res = append(res, errors.NewParseError("Xyz", "body", "", err))
} else {
// validate body object
"""
CID 399294: (#2 of 2): Explicit null dereferenced (FORWARD_NULL)
var_deref_model Validate dereferences null body.User
"""
if err := body.Validate(route.Formats); err != nil {
res = append(res, err)
}
ctx := validate.WithOperationRequest(r.Context())
if err := body.ContextValidate(ctx, route.Formats); err != nil {
res = append(res, err)
}
if len(res) == 0 {
o.Xyz = &body
}
}
}
if len(res) > 0 {
return errors.CompositeValidationError(res...)
}
return nil
}
In the body.validate function we have the below error (coverity errors are shown with """ ):
// Validate validates this backup credential
func (m *Xyz) Validate(formats strfmt.Registry) error {
var res []error
"""
cond_true Condition err != nil, taking true branch
"""
if err := m.validateUser(formats); err != nil {
res = append(res, err)
}
if len(res) > 0 {
return errors.CompositeValidationError(res...)
}
return nil
}
Steps to reproduce
Running Coverity scans on the swagger API project
Environment
swagger version: v0.30.4
go version: 1.20
Coverity: 2022.12.1