Shiny FileInput 错误：“错误登录‘by’参数”

Question

我是 Shiny 的新手，我正在尝试将作为 .R 脚本工作的现有代码转换为 Shiny 应用程序。

原码 - 链接

样本数据- 链接

重点是有一个文件输入，一个人选择一个pdf文件。然后处理 pdf。

这是我的代码：

server <- function(input, output) {
  
  output$contents <- renderTable({
    
    # input$file1 will be NULL initially. After the user selects
    # and uploads a file, head of that data file by default,
    # or all rows if selected, will be shown.
    
    req(input$file1)
    
    test <- pdf_text(input$file1$datapath)
    
    ### Two Sided
    
    test <- gsub("[\r\n]", " ", test)
    list <- strsplit(test, " {2,}") #split anywhere where there are 2 or more consecutive spaces - hopefully only between two paragraphs (if not the output wont make much sense) 
    
    resi <- lapply(list, function(x) {
      unl <- unlist(x)
      len <- length(x)
      uneven <- seq(from = 1, to = len , by = 2)
      even <- seq(from = 2, to = len , by = 2)
      
      uneven <- unl[uneven]
      even <- unl[even]
      uneven <- paste(uneven, collapse = " ")
      even <- paste(even, collapse = " ") #intentionally leave a space between them, one could even use something that is not expected to occur in the document like "frafrafra" and use that in the gsub call later as gsub("(\\d)-frafrafra(\\d)", "\\1\\2", resi)
      return(cbind(uneven, even))
    }) #separate even from uneven rows
    
    resi <- unlist(resi)
    
    resi <- gsub("(\\d)- (\\d)", "\\1\\2", resi) #clean numbers
    resi <- gsub("(\\b)- (\\b)", "\\1\\2", resi) #clean words
    
    resi <- data_frame(line = 1:length(resi), text = resi) #change class/type - vector to dataframe
    
    count <- resi %>% 
      unnest_tokens(word, text)  %>% #split columns into word like elements (tokens)
      count(word, sort = TRUE)       #count frequency and sort in desc order
    
    count$word <- gsub("[^0-9]", NA, count$word) 
    count$num_char <- nchar(count$word)
    
    two_cols <- count %>%
      filter(!is.na(word)) %>%
      filter(n == 1) %>%
      filter(num_char == 7 | num_char == 13 | num_char == 15)
    
   
    if(input$disp == "head") {
      return(head(test))
    }
    else {
      return(two_cols)
    }
    
  })
  
}

代码似乎在测试之前有效<- pdf_text(input$file...

但是，我收到一个错误：错误的“按”参数登录

知道哪里出了问题吗？

编辑：

我正在测试原始代码的第二部分，这似乎是作用域规则的问题。也就是说，在服务器函数中定义一个函数。