refactored for maintainability

internal/validation/forms.go

@@ -0,0 +1,101 @@
+package validation
+
+import (
+	"net/http"
+
+	"git.haelnorr.com/h/golib/hws"
+	"git.haelnorr.com/h/oslstats/internal/notify"
+	"git.haelnorr.com/h/oslstats/internal/throw"
+	"git.haelnorr.com/h/timefmt"
+	"github.com/pkg/errors"
+)
+
+// FormGetter wraps http.Request to get form values
+type FormGetter struct {
+	r      *http.Request
+	checks []*ValidationRule
+}
+
+func NewFormGetter(r *http.Request) *FormGetter {
+	return &FormGetter{r: r, checks: []*ValidationRule{}}
+}
+
+func (f *FormGetter) Get(key string) string {
+	return f.r.FormValue(key)
+}
+
+func (f *FormGetter) getChecks() []*ValidationRule {
+	return f.checks
+}
+
+func (f *FormGetter) AddCheck(check *ValidationRule) {
+	f.checks = append(f.checks, check)
+}
+
+func (f *FormGetter) ValidateChecks() []*ValidationRule {
+	return validate(f)
+}
+
+func (f *FormGetter) String(key string) *StringField {
+	return newStringField(key, f)
+}
+
+func (f *FormGetter) Int(key string) *IntField {
+	return newIntField(key, f)
+}
+
+func (f *FormGetter) Time(key string, format *timefmt.Format) *TimeField {
+	return newTimeField(key, format, f)
+}
+
+func ParseForm(r *http.Request) (*FormGetter, error) {
+	err := r.ParseForm()
+	if err != nil {
+		return nil, errors.Wrap(err, "r.ParseForm")
+	}
+	return NewFormGetter(r), nil
+}
+
+// ParseFormOrNotify attempts to parse the form data and notifies the user on fail
+func ParseFormOrNotify(s *hws.Server, w http.ResponseWriter, r *http.Request) (*FormGetter, bool) {
+	getter, err := ParseForm(r)
+	if err != nil {
+		notify.Warn(s, w, r, "Invalid Form", "Please check your input and try again.", nil)
+		return nil, false
+	}
+	return getter, true
+}
+
+// ParseFormOrError attempts to parse the form data and renders an error page on fail
+func ParseFormOrError(s *hws.Server, w http.ResponseWriter, r *http.Request) (*FormGetter, bool) {
+	getter, err := ParseForm(r)
+	if err != nil {
+		throw.BadRequest(s, w, r, "Invalid form data", err)
+		return nil, false
+	}
+	return getter, true
+}
+
+func (f *FormGetter) Validate() bool {
+	return len(validate(f)) == 0
+}
+
+// ValidateAndNotify runs the provided validation checks and sends a notification for each failed check
+// Returns true if all checks passed
+func (f *FormGetter) ValidateAndNotify(
+	s *hws.Server,
+	w http.ResponseWriter,
+	r *http.Request,
+) bool {
+	return validateAndNotify(s, w, r, f)
+}
+
+// ValidateAndError runs the provided validation checks and renders an error page with all the error messages
+// Returns true if all checks passed
+func (f *FormGetter) ValidateAndError(
+	s *hws.Server,
+	w http.ResponseWriter,
+	r *http.Request,
+) bool {
+	return validateAndError(s, w, r, f)
+}