18F/e-QIP-prototype

package http

import (
    "io/ioutil"
    "net/http"

    "github.com/18F/e-QIP-prototype/api"
)

// ValidateHandler is the handler for validating a payload.
type ValidateHandler struct {
    Log api.LogService
}

// ServeHTTP validates if the payload pass validation procedures.
func (service ValidateHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
    // Read the body of the request (which should be in JSON)
    body, err := ioutil.ReadAll(r.Body)
    if err != nil {
        service.Log.WarnError(api.PayloadEmpty, err, api.LogFields{})
        RespondWithStructuredError(w, api.PayloadEmpty, http.StatusBadRequest)
        return
    }

    // Deserialize the initial payload from a JSON structure
    payload := &api.Payload{}
    if err := payload.Unmarshal(body); err != nil {
        service.Log.WarnError(api.PayloadDeserializeError, err, api.LogFields{})
        RespondWithStructuredError(w, api.PayloadDeserializeError, http.StatusBadRequest)
        return
    }

    entity, err := payload.Entity()
    if err != nil {
        service.Log.WarnError(api.PayloadEntityError, err, api.LogFields{})
        RespondWithStructuredError(w, api.PayloadEntityError, http.StatusBadRequest)

        EncodeErrJSON(w, err)
        return
    }

    location, ok := entity.(*api.Location)
    if !ok {
        service.Log.Warn(api.InvalidValidation, api.LogFields{})
        RespondWithStructuredError(w, api.InvalidValidation, http.StatusBadRequest)
        return
    }

    // Perform minimal field validation on location and send it
    // to the USPS geocoding service. Validation errors of this
    // nature are normal, expected, and parsed by the caller.
    if ok, err := location.Valid(); !ok {
        EncodeErrJSON(w, err)
        return
    }

}