Retry create issue to cope with duplicate keys

go.mod

@@ -45,7 +45,7 @@ require (
 	github.com/glycerine/goconvey v0.0.0-20190315024820-982ee783a72e // indirect
 	github.com/go-redis/redis v6.15.2+incompatible
 	github.com/go-sql-driver/mysql v1.4.1
-	github.com/go-xorm/xorm v0.7.4
+	github.com/go-xorm/xorm v0.7.7-0.20190822154023-17592d96b35b
 	github.com/gogits/chardet v0.0.0-20150115103509-2404f7772561
 	github.com/gogs/cron v0.0.0-20171120032916-9f6c956d3e14
 	github.com/google/go-github/v24 v24.0.1
@@ -117,5 +117,5 @@ require (
 	mvdan.cc/xurls/v2 v2.0.0
 	strk.kbt.io/projects/go/libravatar v0.0.0-20160628055650-5eed7bff870a
 	xorm.io/builder v0.3.5
-	xorm.io/core v0.6.3
+	xorm.io/core v0.7.0
 )

go.sum

@@ -143,6 +143,8 @@ github.com/go-xorm/sqlfiddle v0.0.0-20180821085327-62ce714f951a h1:9wScpmSP5A3Bk
 github.com/go-xorm/sqlfiddle v0.0.0-20180821085327-62ce714f951a/go.mod h1:56xuuqnHyryaerycW3BfssRdxQstACi0Epw/yC5E2xM=
 github.com/go-xorm/xorm v0.7.4 h1:g/NgC590SzqV5VKmdRDNe/K3Holw3YJUCXX28r+rFGw=
 github.com/go-xorm/xorm v0.7.4/go.mod h1:vpza5fydeRgt+stvo9qgMhSNohYqmNt0I1/D6hkCekA=
+github.com/go-xorm/xorm v0.7.7-0.20190822154023-17592d96b35b h1:Y0hWUheXDHpIs7BWtJcykO4d1VOsVDKg1PsP5YJwxxM=
+github.com/go-xorm/xorm v0.7.7-0.20190822154023-17592d96b35b/go.mod h1:nqz2TAsuOHWH2yk4FYWtacCGgdbrcdZ5mF1XadqEHls=
 github.com/gogits/chardet v0.0.0-20150115103509-2404f7772561 h1:deE7ritpK04PgtpyVOS2TYcQEld9qLCD5b5EbVNOuLA=
 github.com/gogits/chardet v0.0.0-20150115103509-2404f7772561/go.mod h1:YgYOrVn3Nj9Tq0EvjmFbphRytDj7JNRoWSStJZWDJTQ=
 github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=
@@ -430,6 +432,7 @@ golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20190221075227-b4e8571b14e0/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190602015325-4c4f7f33c9ed/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190606165138-5da285871e9c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190726091711-fc99dfbffb4e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190730183949-1393eb018365/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -446,6 +449,7 @@ golang.org/x/tools v0.0.0-20190114222345-bf090417da8b/go.mod h1:n7NCudcB/nEzxVGm
 golang.org/x/tools v0.0.0-20190226205152-f727befe758c/go.mod h1:9Yl7xja0Znq3iFh3HoIrodX9oNMXvdceNzlUR8zjMvY=
 golang.org/x/tools v0.0.0-20190312170243-e65039ee4138/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 golang.org/x/tools v0.0.0-20190328211700-ab21143f2384/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
+golang.org/x/tools v0.0.0-20190606050223-4d9ae51c2468/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
 golang.org/x/tools v0.0.0-20190606124116-d0a3d012864b/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
 golang.org/x/tools v0.0.0-20190729092621-ff9f1409240a/go.mod h1:jcCCGcm9btYwXyDqrUWc6MKQKKGJCWEQ3AfLSRIbEuI=
 golang.org/x/tools v0.0.0-20190731214159-1e85ed8060aa h1:kwa/4M1dbmhZqOIqYiTtbA6JrvPwo1+jqlub2qDXX90=
@@ -454,6 +458,7 @@ google.golang.org/api v0.3.1/go.mod h1:6wY9I6uQWHQ8EM57III9mq/AjF+i8G65rmVagqKMt
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.2.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
+google.golang.org/appengine v1.6.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/appengine v1.6.1 h1:QzqyMA1tlu6CgqCDUtU9V+ZKhLFT2dkJuANu5QaxI3I=
 google.golang.org/appengine v1.6.1/go.mod h1:i06prIuMbXzDqacNJfV5OdTW448YApPu5ww/cMBSeb0=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
@@ -509,3 +514,5 @@ xorm.io/builder v0.3.5 h1:EilU39fvWDxjb1cDaELpYhsF+zziRBhew8xk4pngO+A=
 xorm.io/builder v0.3.5/go.mod h1:ZFbByS/KxZI1FKRjL05PyJ4YrK2bcxlUaAxdum5aTR8=
 xorm.io/core v0.6.3 h1:n1NhVZt1s2oLw1BZfX2ocIJsHyso259uPgg63BGr37M=
 xorm.io/core v0.6.3/go.mod h1:8kz/C6arVW/O9vk3PgCiMJO2hIAm1UcuOL3dSPyZ2qo=
+xorm.io/core v0.7.0 h1:hKxuOKWZNeiFQsSuGet/KV8HZ788hclvAl+7azx3tkM=
+xorm.io/core v0.7.0/go.mod h1:TuOJjIVa7e3w/rN8tDcAvuLBMtwzdHPbyOzE6Gk1EUI=

models/issue.go

@@ -5,7 +5,6 @@
 package models
 
 import (
-	"errors"
 	"fmt"
 	"path"
 	"regexp"
@@ -74,6 +73,7 @@ var (
 
 const issueTasksRegexpStr = `(^\s*[-*]\s\[[\sx]\]\s.)|(\n\s*[-*]\s\[[\sx]\]\s.)`
 const issueTasksDoneRegexpStr = `(^\s*[-*]\s\[[x]\]\s.)|(\n\s*[-*]\s\[[x]\]\s.)`
+const issueMaxDupIndexAttempts = 3
 
 func init() {
 	issueTasksPat = regexp.MustCompile(issueTasksRegexpStr)
@@ -1031,36 +1031,9 @@ type NewIssueOptions struct {
 	IsPull      bool
 }
 
-// GetMaxIndexOfIssue returns the max index on issue
-func GetMaxIndexOfIssue(repoID int64) (int64, error) {
-	return getMaxIndexOfIssue(x, repoID)
-}
-
-func getMaxIndexOfIssue(e Engine, repoID int64) (int64, error) {
-	var (
-		maxIndex int64
-		has      bool
-		err      error
-	)
-
-	has, err = e.SQL("SELECT COALESCE((SELECT MAX(`index`) FROM issue WHERE repo_id = ?),0)", repoID).Get(&maxIndex)
-	if err != nil {
-		return 0, err
-	} else if !has {
-		return 0, errors.New("Retrieve Max index from issue failed")
-	}
-	return maxIndex, nil
-}
-
 func newIssue(e *xorm.Session, doer *User, opts NewIssueOptions) (err error) {
 	opts.Issue.Title = strings.TrimSpace(opts.Issue.Title)
 
-	maxIndex, err := getMaxIndexOfIssue(e, opts.Issue.RepoID)
-	if err != nil {
-		return err
-	}
-	opts.Issue.Index = maxIndex + 1
-
 	if opts.Issue.MilestoneID > 0 {
 		milestone, err := getMilestoneByRepoID(e, opts.Issue.RepoID, opts.Issue.MilestoneID)
 		if err != nil && !IsErrMilestoneNotExist(err) {
@@ -1109,10 +1082,31 @@ func newIssue(e *xorm.Session, doer *User, opts NewIssueOptions) (err error) {
 	}
 
 	// Milestone and assignee validation should happen before insert actual object.
-	if _, err = e.Insert(opts.Issue); err != nil {
+
+	// There's no good way to identify a duplicate key error in database/sql; brute force some retries
+	dupIndexAttempts := issueMaxDupIndexAttempts
+	for {
+		_, err := e.SetExpr("`index`", "coalesce(MAX(`index`),0)+1").
+			Where("repo_id=?", opts.Issue.RepoID).
+			Insert(opts.Issue)
+		if err == nil {
+			break
+		}
+
+		dupIndexAttempts--
+		if dupIndexAttempts <= 0 {
+			return err
+		}
+	}
+
+	inserted, err := getIssueByID(e, opts.Issue.ID)
+	if err != nil {
 		return err
 	}
 
+	// Patch Index with the value calculated by the database
+	opts.Issue.Index = inserted.Index
+
 	if opts.Issue.MilestoneID > 0 {
 		if err = changeMilestoneAssign(e, doer, opts.Issue, -1); err != nil {
 			return err

routers/api/v1/repo/pull.go

@@ -252,15 +252,8 @@ func CreatePullRequest(ctx *context.APIContext, form api.CreatePullRequestOption
 		deadlineUnix = timeutil.TimeStamp(form.Deadline.Unix())
 	}
 
-	maxIndex, err := models.GetMaxIndexOfIssue(repo.ID)
-	if err != nil {
-		ctx.ServerError("GetPatch", err)
-		return
-	}
-
 	prIssue := &models.Issue{
 		RepoID:       repo.ID,
-		Index:        maxIndex + 1,
 		Title:        form.Title,
 		PosterID:     ctx.User.ID,
 		Poster:       ctx.User,

routers/repo/pull.go

@@ -710,15 +710,8 @@ func CompareAndPullRequestPost(ctx *context.Context, form auth.CreateIssueForm)
 		return
 	}
 
-	maxIndex, err := models.GetMaxIndexOfIssue(repo.ID)
-	if err != nil {
-		ctx.ServerError("GetPatch", err)
-		return
-	}
-
 	pullIssue := &models.Issue{
 		RepoID:      repo.ID,
-		Index:       maxIndex + 1,
 		Title:       form.Title,
 		PosterID:    ctx.User.ID,
 		Poster:      ctx.User,