HTMLRenderer crashes when special characters appear in digests

[herrsimon]

Hello,

I just tried to generate a report out of a large number (~5000) of emails and scholar-alert-digest crashed with the following backtrace:

panic: template: layout:29666: unexpected "\\" in command

goroutine 1 [running]:
html/template.Must(...)
        /usr/lib/go/src/html/template/template.go:372
github.com/bzz/scholar-alert-digest/templates.(*HTMLRenderer).Render(0xc006d3f230, 0xafe5e0, 0xc000010018, 0xc00642d5c0, 0xc0022c1470, 0x0)
        /home/simon/git/scholar-alert-digest/templates/templates.go:232 +0x48a
main.main()
        /home/simon/git/scholar-alert-digest/main.go:154 +0x542

Unfortunately I don't know which email actually caused this but it looks like some sort of escaping problem before passing things to the go templating engine.

Command was go run main.go -l scholaralert -authors -html -refs on the current master branch

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[bzz]

Hi @herrsimon ! Thank you for 🐞 report and I'm sorry to hear that it did not work for you and for a delay.
Let me look into it and get back to you here soon.

Meanwhile, could you please check if the same happens with -json (or -mark) instead of -html ?

[reed-foster]

I've seen the same issue caused by LaTeX math expressions in an abstract/title (e.g. \lambda_{{\bf {k}}}). The issue is resolved by using -json or not providing the -html flag. I don't have much familiarity with go, but perhaps there's a way to make the html body a raw string or somehow escape the {{ and }} characters in the html body before passing it to the template? Since the LaTeX isn't getting rendered it'd also seem acceptable to just remove the offending characters in any of the abstracts/titles.

I was able to fix it with:

--- a/templates/templates.go
+++ b/templates/templates.go
@@ -6,6 +6,7 @@ import (
        "bytes"
        "encoding/json"
        "fmt"
+       "strings"
        "html/template"
        "io"
        "log"
@@ -267,7 +268,8 @@ func (r *HTMLRenderer) Render(out io.Writer, st *papers.Stats, unread, read pape
        // rootLayout requires 3 sub-templates
        title := `{{ define "title" }}scholar alert digest{{ end }}`
        style := fmt.Sprintf(`{{ define "style" }}%s{{ end }}`, r.style)
-       body := fmt.Sprintf(`{{ define "body" }}%s{{ end }}`, htmlBuf.String())
+       body_str := strings.Replace(strings.Replace(htmlBuf.String(), "{{", "{ {", -1), "}}", "} }", -1)
+       body := fmt.Sprintf(`{{ define "body" }}%s{{ end }}`, body_str)