3) list services JSON errors

characteristic_types.go

@@ -58,13 +58,13 @@ func (c *CharacteristicTypes) marshal() ([]byte, error) {
 	return json.Marshal(&CharacteristicTypesJSON{CharacteristicTypes: c})
 }
 
-func (c CharacteristicTypeService) list(val *url.Values) (entity, error) {
+func (c CharacteristicTypeService) list(val *url.Values) (entity, *appError) {
 	if val == nil {
-		return nil, errors.New("must provide options")
+		return nil, ErrMustProvideOptionsJSON
 	}
 	var opt ListOptions
 	if err := schemaDecoder.Decode(&opt, *val); err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 
 	var vals []interface{}
@@ -91,7 +91,7 @@ func (c CharacteristicTypeService) list(val *url.Values) (entity, error) {
 	characteristic_types := make(CharacteristicTypes, 0)
 	err := DBH.Select(&characteristic_types, sql, vals...)
 	if err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 	return &characteristic_types, nil
 }

characteristics.go

@@ -60,13 +60,13 @@ func (c *Characteristics) marshal() ([]byte, error) {
 	return json.Marshal(&CharacteristicsJSON{Characteristics: c})
 }
 
-func (c CharacteristicService) list(val *url.Values) (entity, error) {
+func (c CharacteristicService) list(val *url.Values) (entity, *appError) {
 	if val == nil {
-		return nil, errors.New("must provide options")
+		return nil, ErrMustProvideOptionsJSON
 	}
 	var opt ListOptions
 	if err := schemaDecoder.Decode(&opt, *val); err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 
 	var vals []interface{}
@@ -93,7 +93,7 @@ func (c CharacteristicService) list(val *url.Values) (entity, error) {
 	characteristics := make(Characteristics, 0)
 	err := DBH.Select(&characteristics, sql, vals...)
 	if err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 	return &characteristics, nil
 }

entities.go

@@ -11,7 +11,7 @@ type getter interface {
 }
 
 type lister interface {
-	list(*url.Values) (entity, error)
+	list(*url.Values) (entity, *appError)
 }
 
 type updater interface {

handlers.go

@@ -79,7 +79,7 @@ func Handler() http.Handler {
 	m.Handle("/authenticate", tokenHandler(j.GenerateToken())).Methods("POST")
 
 	// Auth routes
-	m.Handle("/users", j.Secure(http.HandlerFunc(handleLister(userService)), verifyClaims)).Methods("GET")
+	m.Handle("/users", j.Secure(errorHandler(handleLister(userService)), verifyClaims)).Methods("GET")
 	m.Handle("/users", j.Secure(http.HandlerFunc(handleCreater(userService)), verifyClaims)).Methods("POST")
 	m.Handle("/users/{Id:.+}", j.Secure(errorHandler(handleGetter(userService)), verifyClaims)).Methods("GET")
 	m.Handle("/users/{Id:.+}", j.Secure(http.HandlerFunc(handleUpdater(userService)), verifyClaims)).Methods("PUT")
@@ -94,19 +94,19 @@ func Handler() http.Handler {
 	}
 
 	routes := []r{
-		// r{handleLister(speciesService), "GET", "/species"},
+		r{handleLister(speciesService), "GET", "/species"},
 		// r{handleCreater(speciesService), "POST", "/species"},
 		r{handleGetter(speciesService), "GET", "/species/{Id:.+}"},
 		// r{handleUpdater(speciesService), "PUT", "/species/{Id:.+}"},
-		// r{handleLister(strainService), "GET", "/strains"},
+		r{handleLister(strainService), "GET", "/strains"},
 		// r{handleCreater(strainService), "POST", "/strains"},
 		r{handleGetter(strainService), "GET", "/strains/{Id:.+}"},
 		// r{handleUpdater(strainService), "PUT", "/strains/{Id:.+}"},
-		// r{handleLister(characteristicService), "GET", "/characteristics"},
+		r{handleLister(characteristicService), "GET", "/characteristics"},
 		r{handleGetter(characteristicService), "GET", "/characteristics/{Id:.+}"},
-		// r{handleLister(characteristicTypeService), "GET", "/characteristicTypes"},
+		r{handleLister(characteristicTypeService), "GET", "/characteristicTypes"},
 		r{handleGetter(characteristicTypeService), "GET", "/characteristicTypes/{Id:.+}"},
-		// r{handleLister(measurementService), "GET", "/measurements"},
+		r{handleLister(measurementService), "GET", "/measurements"},
 		r{handleGetter(measurementService), "GET", "/measurements/{Id:.+}"},
 	}
 
@@ -138,21 +138,21 @@ func handleGetter(g getter) errorHandler {
 	}
 }
 
-func handleLister(l lister) http.HandlerFunc {
+func handleLister(l lister) errorHandler {
-	return func(w http.ResponseWriter, r *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) *appError {
 		opt := r.URL.Query()
 		opt.Add("Genus", mux.Vars(r)["genus"])
 
-		es, err := l.list(&opt)
+		es, appErr := l.list(&opt)
-		if err != nil {
+		if appErr != nil {
-			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return appErr
-			return
 		}
 		data, err := es.marshal()
 		if err != nil {
-			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return newJSONError(err, http.StatusInternalServerError)
 		}
 		w.Write(data)
+		return nil
 	}
 }
 

helpers.go

@@ -1,6 +1,15 @@
 package main
 
-import "fmt"
+import (
+	"errors"
+	"fmt"
+	"net/http"
+)
+
+var (
+	ErrMustProvideOptions     = errors.New("Must provide necessary options")
+	ErrMustProvideOptionsJSON = newJSONError(ErrMustProvideOptions, http.StatusBadRequest)
+)
 
 // ListOptions specifies general pagination options for fetching a list of results
 type ListOptions struct {

measurements.go

@@ -67,9 +67,9 @@ func (m *Measurements) marshal() ([]byte, error) {
 	return json.Marshal(&MeasurementsJSON{Measurements: m})
 }
 
-func (m MeasurementService) list(val *url.Values) (entity, error) {
+func (m MeasurementService) list(val *url.Values) (entity, *appError) {
 	if val == nil {
-		return nil, errors.New("must provide options")
+		return nil, ErrMustProvideOptionsJSON
 	}
 	var opt struct {
 		ListOptions
@@ -77,7 +77,7 @@ func (m MeasurementService) list(val *url.Values) (entity, error) {
 		Characteristics []int64 `schema:"characteristic[]"`
 	}
 	if err := schemaDecoder.Decode(&opt, *val); err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 
 	var vals []interface{}
@@ -134,7 +134,7 @@ func (m MeasurementService) list(val *url.Values) (entity, error) {
 	measurements := make(Measurements, 0)
 	err := DBH.Select(&measurements, sql, vals...)
 	if err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 	return &measurements, nil
 }

species.go

@@ -72,13 +72,13 @@ func (s SpeciesService) unmarshal(b []byte) (entity, error) {
 	return sj.Species, err
 }
 
-func (s SpeciesService) list(val *url.Values) (entity, error) {
+func (s SpeciesService) list(val *url.Values) (entity, *appError) {
 	if val == nil {
-		return nil, errors.New("must provide options")
+		return nil, ErrMustProvideOptionsJSON
 	}
 	var opt ListOptions
 	if err := schemaDecoder.Decode(&opt, *val); err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 
 	var vals []interface{}
@@ -107,7 +107,7 @@ func (s SpeciesService) list(val *url.Values) (entity, error) {
 	species := make(ManySpecies, 0)
 	err := DBH.Select(&species, sql, vals...)
 	if err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 	return &species, nil
 }

strains.go

@@ -74,13 +74,13 @@ func (s StrainService) unmarshal(b []byte) (entity, error) {
 	return sj.Strain, err
 }
 
-func (s StrainService) list(val *url.Values) (entity, error) {
+func (s StrainService) list(val *url.Values) (entity, *appError) {
 	if val == nil {
-		return nil, errors.New("must provide options")
+		return nil, ErrMustProvideOptionsJSON
 	}
 	var opt ListOptions
 	if err := schemaDecoder.Decode(&opt, *val); err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 
 	var vals []interface{}
@@ -109,7 +109,7 @@ func (s StrainService) list(val *url.Values) (entity, error) {
 	strains := make(Strains, 0)
 	err := DBH.Select(&strains, sql, vals...)
 	if err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 	return &strains, nil
 }

users.go

@@ -89,19 +89,19 @@ func (u *User) validate() error {
 	return nil
 }
 
-func (u UserService) list(val *url.Values) (entity, error) {
+func (u UserService) list(val *url.Values) (entity, *appError) {
 	if val == nil {
-		return nil, errors.New("must provide options")
+		return nil, ErrMustProvideOptionsJSON
 	}
 	var opt ListOptions
 	if err := schemaDecoder.Decode(&opt, *val); err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 
 	users := make(Users, 0)
 	sql := `SELECT * FROM users;`
 	if err := DBH.Select(&users, sql); err != nil {
-		return nil, err
+		return nil, newJSONError(err, http.StatusInternalServerError)
 	}
 	return &users, nil
 }