需要pandoc 1.12.3或更高版本，但未找到（R闪亮）

我从托管在服务器上的我的应用程序闪亮生成pdf报告时遇到问题。

该应用程序运行正常，但是当我按下按钮下载报告时，出现此错误：

 pandoc version 1.12.3 or higher is required and was not found.

问题是，如果键入，pandoc -v我会得到：

 pandoc 1.12.3.3
 Compiled with texmath 0.6.6, highlighting-kate 0.5.6.1.
Syntax highlighting is supported for the following languages:
    actionscript, ada, apache, asn1, asp, awk, bash, bibtex, boo, c, changelog,
    clojure, cmake, coffee, coldfusion, commonlisp, cpp, cs, css, curry, d,
    diff, djangotemplate, doxygen, doxygenlua, dtd, eiffel, email, erlang,
    fortran, fsharp, gnuassembler, go, haskell, haxe, html, ini, java, javadoc,
    javascript, json, jsp, julia, latex, lex, literatecurry, literatehaskell,
    lua, makefile, mandoc, markdown, matlab, maxima, metafont, mips, modelines,
    modula2, modula3, monobasic, nasm, noweb, objectivec, objectivecpp, ocaml,
    octave, pascal, perl, php, pike, postscript, prolog, python, r,
    relaxngcompact, restructuredtext, rhtml, roff, ruby, rust, scala, scheme,
    sci, sed, sgml, sql, sqlmysql, sqlpostgresql, tcl, texinfo, verilog, vhdl,
    xml, xorg, xslt, xul, yacc, yaml
 Default user data directory: /home/daniele/.pandoc
 Copyright (C) 2006-2013 John MacFarlane
 Web:  http://johnmacfarlane.net/pandoc
 This is free software; see the source for copying conditions.  There is no
 warranty, not even for merchantability or fitness for a particular purpose.

所以我想我有合适的版本。TexLive也已安装，并且路径在$PATH。

服务器

library(shiny)
library(drsmooth)
library(shinyBS)
library(knitr)
library(xtable)
library(rmarkdown)

shinyServer(function(input, output,session) { 

 output$downloadReport <- downloadHandler(
filename = function() {
  paste('report', sep = '.','pdf')
},

content = function(file) {
  src <- normalizePath('report.Rmd')

  # temporarily switch to the temp dir, in case you do not have write
  # permission to the current working directory
  owd <- setwd(tempdir())
  on.exit(setwd(owd))
  file.copy(src, 'report.Rmd')

  library(rmarkdown)
  out <- render('report.Rmd')
  file.rename(out, file)
})

output$tb <- renderUI({
             p(h4("Report")),
            "Dowload a the report of your analysis in a pdf format",
            tags$br(),downloadButton('downloadReport',label="Download report"),
            tags$em("This option will be available soon")
     })
})

* report.Rmd *不包含任何类型的计算，仅是文本。pdf生成可以在我的本地版本（MacOS）上正常运行，但不能在服务器上运行。

如果需要，我在这里提供其他信息。