sort lexicographically data fields (#25)

* sort lexicographically data fields

Fixes #23

* remove reduntant error check

This doesn't look nice with the rest of the code.

I think error handling on writes can be ignored here or addressed in a
separate PR

src/github.com/matrix-org/rageshake/submit.go

@@ -22,7 +22,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"github.com/google/go-github/github"
 	"io"
 	"io/ioutil"
 	"log"
@@ -32,9 +31,12 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"sort"
 	"strconv"
 	"strings"
 	"time"
+
+	"github.com/google/go-github/github"
 )
 
 var maxPayloadSize = 1024 * 1024 * 55 // 55 MB
@@ -79,6 +81,37 @@ type parsedPayload struct {
 	FileErrors []string
 }
 
+func (p parsedPayload) WriteTo(out io.Writer) {
+	fmt.Fprintf(
+		out,
+		"%s\n\nNumber of logs: %d\nApplication: %s\n",
+		p.UserText, len(p.Logs), p.AppName,
+	)
+	fmt.Fprintf(out, "Labels: %s\n", strings.Join(p.Labels, ", "))
+
+	var dataKeys []string
+	for k := range p.Data {
+		dataKeys = append(dataKeys, k)
+	}
+	sort.Strings(dataKeys)
+	for _, k := range dataKeys {
+		v := p.Data[k]
+		fmt.Fprintf(out, "%s: %s\n", k, v)
+	}
+	if len(p.LogErrors) > 0 {
+		fmt.Fprint(out, "Log upload failures:\n")
+		for _, e := range p.LogErrors {
+			fmt.Fprintf(out, "    %s\n", e)
+		}
+	}
+	if len(p.FileErrors) > 0 {
+		fmt.Fprint(out, "Attachment upload failures:\n")
+		for _, e := range p.FileErrors {
+			fmt.Fprintf(out, "    %s\n", e)
+		}
+	}
+}
+
 type submitResponse struct {
 	ReportURL string `json:"report_url,omitempty"`
 }
@@ -420,31 +453,9 @@ func saveLogPart(logNum int, filename string, reader io.Reader, reportDir string
 }
 
 func (s *submitServer) saveReport(ctx context.Context, p parsedPayload, reportDir, listingURL string) (*submitResponse, error) {
-	resp := submitResponse{}
-
 	var summaryBuf bytes.Buffer
-	fmt.Fprintf(
+	resp := submitResponse{}
-		&summaryBuf,
+	p.WriteTo(&summaryBuf)
-		"%s\n\nNumber of logs: %d\nApplication: %s\n",
-		p.UserText, len(p.Logs), p.AppName,
-	)
-	fmt.Fprintf(&summaryBuf, "Labels: %s\n", strings.Join(p.Labels, ", "))
-	for k, v := range p.Data {
-		fmt.Fprintf(&summaryBuf, "%s: %s\n", k, v)
-	}
-	if len(p.LogErrors) > 0 {
-		fmt.Fprint(&summaryBuf, "Log upload failures:\n")
-		for _, e := range p.LogErrors {
-			fmt.Fprintf(&summaryBuf, "    %s\n", e)
-		}
-	}
-	if len(p.FileErrors) > 0 {
-		fmt.Fprint(&summaryBuf, "Attachment upload failures:\n")
-		for _, e := range p.FileErrors {
-			fmt.Fprintf(&summaryBuf, "    %s\n", e)
-		}
-	}
-
 	if err := gzipAndSave(summaryBuf.Bytes(), reportDir, "details.log.gz"); err != nil {
 		return nil, err
 	}
@@ -497,7 +508,13 @@ func buildGithubIssueRequest(p parsedPayload, listingURL string) github.IssueReq
 
 	var bodyBuf bytes.Buffer
 	fmt.Fprintf(&bodyBuf, "User message:\n\n%s\n\n", p.UserText)
-	for k, v := range p.Data {
+	var dataKeys []string
+	for k := range p.Data {
+		dataKeys = append(dataKeys, k)
+	}
+	sort.Strings(dataKeys)
+	for _, k := range dataKeys {
+		v := p.Data[k]
 		fmt.Fprintf(&bodyBuf, "%s: `%s`\n", k, v)
 	}
 	fmt.Fprintf(&bodyBuf, "[Logs](%s)", listingURL)

src/github.com/matrix-org/rageshake/submit_test.go

@@ -17,6 +17,7 @@ limitations under the License.
 package main
 
 import (
+	"bytes"
 	"compress/gzip"
 	"io"
 	"io/ioutil"
@@ -426,3 +427,59 @@ Content-Disposition: form-data; name="text"
 		t.Errorf("Body: got %s, want %s", *issueReq.Body, expectedBody)
 	}
 }
+
+func TestTestSortDataKeys(t *testing.T) {
+	expect := `
+Number of logs: 0
+Application: 
+Labels: 
+User-Agent: xxx
+Version: 1
+device_id: id
+user_id: id
+	`
+	expect = strings.TrimSpace(expect)
+	sample := []struct {
+		data map[string]string
+	}{
+		{
+			map[string]string{
+				"Version":    "1",
+				"User-Agent": "xxx",
+				"user_id":    "id",
+				"device_id":  "id",
+			},
+		},
+		{
+			map[string]string{
+				"user_id":    "id",
+				"device_id":  "id",
+				"Version":    "1",
+				"User-Agent": "xxx",
+			},
+		},
+	}
+	var buf bytes.Buffer
+	for _, v := range sample {
+		p := parsedPayload{Data: v.data}
+		buf.Reset()
+		p.WriteTo(&buf)
+		got := strings.TrimSpace(buf.String())
+		if got != expect {
+			t.Errorf("expected %s got %s", expect, got)
+		}
+	}
+
+	for k, v := range sample {
+		p := parsedPayload{Data: v.data}
+		res := buildGithubIssueRequest(p, "")
+		got := *res.Body
+		if k == 0 {
+			expect = got
+			continue
+		}
+		if got != expect {
+			t.Errorf("expected %s got %s", expect, got)
+		}
+	}
+}