factored out some common error messages to error objects that can be referenced

community.go

@@ -19,8 +19,15 @@ import (
 	"git.erbosoft.com/amy/amsterdam/ui"
 	"git.erbosoft.com/amy/amsterdam/util"
 	"github.com/biter777/countries"
+	"github.com/labstack/echo/v4"
 )
 
+// ENOJOIN is an error for not being permitted to join a community.
+var ENOJOIN *echo.HTTPError = echo.NewHTTPError(http.StatusForbidden, "you are not permitted to join this community")
+
+// ENOUNJOIN is an error for not being permitted to unjoin a community.
+var ENOUNJOIN *echo.HTTPError = echo.NewHTTPError(http.StatusForbidden, "you are not permitted to unjoin this community")
+
 /* ShowCommunity renders the community profile display.
  * Parameters:
  *     ctxt - The AmContext for the request.
@@ -163,7 +170,7 @@ func JoinCommunity(ctxt ui.AmContext) (string, any) {
 			return "error", err
 		}
 	} else {
-		return "error", "you are not permitted to join this community"
+		return "error", ENOJOIN
 	}
 	return "redirect", fmt.Sprintf("/comm/%s/profile", comm.Alias)
 }
@@ -236,8 +243,7 @@ func UnjoinCommunity(ctxt ui.AmContext) (string, any) {
 		return "redirect", fmt.Sprintf("/comm/%s/profile", comm.Alias)
 	}
 	if lock {
-		ctxt.SetRC(http.StatusForbidden)
+		return "error", ENOUNJOIN
-		return "error", "you are not permitted to unjoin this community"
 	}
 	ctxt.VarMap().Set("comm", comm)
 	ctxt.VarMap().Set("amsterdam_pageTitle", "Unjoin Community")
@@ -263,8 +269,7 @@ func UnjoinCommunityConfirm(ctxt ui.AmContext) (string, any) {
 		return "redirect", fmt.Sprintf("/comm/%s/profile", comm.Alias)
 	}
 	if lock {
-		ctxt.SetRC(http.StatusForbidden)
+		return "error", ENOUNJOIN
-		return "error", "you are not permitted to unjoin this community"
 	}
 	if ctxt.FormFieldIsSet("cancel") {
 		return "redirect", fmt.Sprintf("/comm/%s/profile", comm.Alias)
@@ -277,7 +282,7 @@ func UnjoinCommunityConfirm(ctxt ui.AmContext) (string, any) {
 		ctxt.ClearCommunityContext()
 		return "redirect", fmt.Sprintf("/comm/%s/profile", comm.Alias)
 	}
-	return "error", "unknown button pressed to confirm unjoin"
+	return "error", EBUTTON
 }
 
 /* MemberList lists the members of the community.

communityadmin.go

@@ -344,7 +344,7 @@ func EditCommunityLogo(ctxt ui.AmContext) (string, any) {
 		happy = true
 		return "redirect", "/comm/" + comm.Alias + "/admin/profile"
 	}
-	return "error", "invalid button detected in logo upload"
+	return "error", EBUTTON
 }
 
 /* CreateCommunityForm renders the form for creating a new community.

conference.go

@@ -293,7 +293,7 @@ func NewTopic(ctxt ui.AmContext) (string, any) {
 		return "framed", "attachment_upload.jet"
 	}
 
-	return "error", "invalid button clicked on form"
+	return "error", EBUTTON
 }
 
 /* breakRange breaks up a post range into two elements.
@@ -710,7 +710,7 @@ func PostInTopic(ctxt ui.AmContext) (string, any) {
 	} else if ctxt.FormFieldIsSet("posttopics") {
 		returnURL = fmt.Sprintf("/comm/%s/conf/%s", comm.Alias, ctxt.GetScratch("currentAlias"))
 	} else {
-		return "error", "unknown post button"
+		return "error", EBUTTON
 	}
 
 	// Check for slippage.

conference_ops.go

@@ -77,7 +77,7 @@ func AttachmentUpload(ctxt ui.AmContext) (string, any) {
 		ctxt.VarMap().Set("errorMessage", err.Error())
 		return "framed", "attachment_upload.jet"
 	}
-	return "error", "invalid button clicked on form"
+	return "error", EBUTTON
 }
 
 /* AttachmentSend sends the data of an attachment to the browser.

errors.go

@@ -10,6 +10,7 @@
 package main
 
 import (
+	"errors"
 	"net/http"
 
 	"git.erbosoft.com/amy/amsterdam/ui"
@@ -17,12 +18,21 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
+// EBUTTON is the standard error for an unknown button.
+var EBUTTON error = errors.New("invalid or unknown button pressed")
+
+// ELOGIN is the standard error for not being logged in
+var ELOGIN error = errors.New("you are not logged in")
+
 // ENOPERM is the standard "not permitted" error message.
 var ENOPERM *echo.HTTPError = echo.NewHTTPError(http.StatusForbidden, "you are not permitted to perform this operation")
 
 // ENOACCESS is the standard "no access" error message.
 var ENOACCESS *echo.HTTPError = echo.NewHTTPError(http.StatusForbidden, "you are not permitted to access this page")
 
+// EPARAM is an error for no parameters being specified.
+var EPARAM error = errors.New("no parameters specified")
+
 /* NotImplPage is used for all TODO links, to show that something hasn't yet been implemented.
  * Parameters:
  *     ctxt - The AmContext for the request.

invites.go

@@ -100,7 +100,7 @@ func InviteSend(ctxt ui.AmContext) (string, any) {
 	if ctxt.FormFieldIsSet("cancel") {
 		return "redirect", backlink
 	} else if !ctxt.FormFieldIsSet("send") {
-		return "error", "invalid command"
+		return "error", EBUTTON
 	}
 	var comm *database.Community
 	if ctxt.FormFieldIsSet("cid") {
@@ -112,7 +112,7 @@ func InviteSend(ctxt ui.AmContext) (string, any) {
 			return "error", err
 		}
 	} else {
-		return "error", "no parameters specified"
+		return "error", EPARAM
 	}
 	mode := "community"
 	var conf *database.Conference = nil

login.go

@@ -21,6 +21,9 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
+// ENOACCOUNT is an error thrown if you have to log out before creating a new account.
+var ENOACCOUNT error = errors.New("you cannot create a new account while logged in on an existing one. You must log out first")
+
 /* LoginForm renders the Amsterdam login form.
  * Parameters:
  *     ctxt - The AmContext for the request.
@@ -170,7 +173,7 @@ func VerifyEmailForm(ctxt ui.AmContext) (string, any) {
 	// If user is not logged in, this is an error.
 	user := ctxt.CurrentUser()
 	if user.IsAnon {
-		return "error", "you must log in before you can verify your account's E-mail address"
+		return "error", ELOGIN
 	}
 
 	// If user is already verified, this is a no-op.
@@ -212,7 +215,7 @@ func VerifyEMail(ctxt ui.AmContext) (string, any) {
 	// If user is not logged in, this is an error.
 	user := ctxt.CurrentUser()
 	if user.IsAnon {
-		return "error", "you must log in before you can verify your account's E-mail address"
+		return "error", ELOGIN
 	}
 
 	dlg, err := ui.AmLoadDialog("verify_email")
@@ -279,7 +282,7 @@ func NewAccountUserAgreement(ctxt ui.AmContext) (string, any) {
 
 	// If user is already logged in, this is an error.
 	if !ctxt.CurrentUser().IsAnon {
-		return "error", "you cannot create a new account while logged in on an existing one. You must log out first"
+		return "error", ENOACCOUNT
 	}
 
 	ctxt.SetLeftMenu("top")
@@ -305,7 +308,7 @@ func NewAccountForm(ctxt ui.AmContext) (string, any) {
 
 	// If user is already logged in, this is an error.
 	if !ctxt.CurrentUser().IsAnon {
-		return "error", "you cannot create a new account while logged in on an existing one. You must log out first"
+		return "error", ENOACCOUNT
 	}
 
 	dlg, err := ui.AmLoadDialog("newaccount")
@@ -327,7 +330,7 @@ func NewAccountForm(ctxt ui.AmContext) (string, any) {
 func NewAccount(ctxt ui.AmContext) (string, any) {
 	// If user is already logged in, this is an error.
 	if !ctxt.CurrentUser().IsAnon {
-		return "error", "you cannot create a new account while logged in on an existing one. You must log out first"
+		return "error", ENOACCOUNT
 	}
 
 	dlg, err := ui.AmLoadDialog("newaccount")

userdata.go

@@ -50,7 +50,7 @@ func EditProfileForm(ctxt ui.AmContext) (string, any) {
 	}
 	u := ctxt.CurrentUser()
 	if u.IsAnon {
-		return "error", "you are not logged in"
+		return "error", ELOGIN
 	}
 	dlg, err := ui.AmLoadDialog("profile")
 	if err == nil {
@@ -108,7 +108,7 @@ func EditProfileForm(ctxt ui.AmContext) (string, any) {
 func EditProfile(ctxt ui.AmContext) (string, any) {
 	u := ctxt.CurrentUser()
 	if u.IsAnon {
-		return "error", "you are not logged in"
+		return "error", ELOGIN
 	}
 	dlg, err := ui.AmLoadDialog("profile")
 	if err == nil {
@@ -219,7 +219,7 @@ func ProfilePhotoForm(ctxt ui.AmContext) (string, any) {
 	}
 	u := ctxt.CurrentUser()
 	if u.IsAnon {
-		return "error", "you are not logged in"
+		return "error", ELOGIN
 	}
 	ci, err := u.ContactInfo(ctxt.Ctx())
 	if err == nil {
@@ -242,7 +242,7 @@ func ProfilePhotoForm(ctxt ui.AmContext) (string, any) {
 func ProfilePhoto(ctxt ui.AmContext) (string, any) {
 	u := ctxt.CurrentUser()
 	if u.IsAnon {
-		return "error", "you are not logged in"
+		return "error", ELOGIN
 	}
 	ci, err := u.ContactInfo(ctxt.Ctx())
 	if err != nil {
@@ -313,7 +313,7 @@ func ProfilePhoto(ctxt ui.AmContext) (string, any) {
 		happy = true
 		return "redirect", "/profile?tgt=" + url.QueryEscape(target)
 	}
-	return "error", "invalid button detected in photo upload"
+	return "error", EBUTTON
 }
 
 /* ShowProfile displays a user's profile.
@@ -441,7 +441,7 @@ func ShowProfile(ctxt ui.AmContext) (string, any) {
 func QuickEMail(ctxt ui.AmContext) (string, any) {
 	me := ctxt.CurrentUser()
 	if me.IsAnon {
-		return "error", "you are not logged in"
+		return "error", ELOGIN
 	}
 	myCI, err := me.ContactInfo(ctxt.Ctx())
 	if err != nil {
@@ -481,7 +481,7 @@ func QuickEMail(ctxt ui.AmContext) (string, any) {
 func Hotlist(ctxt ui.AmContext) (string, any) {
 	me := ctxt.CurrentUser()
 	if me.IsAnon {
-		return "error", "you are not logged in"
+		return "error", ELOGIN
 	}
 	hotlist, err := database.AmGetConferenceHotlist(ctxt.Ctx(), me)
 	if err != nil {