Preview webR REPL link contents without writing files to disk

Decodes a webR URL and returns information about the embedded files without actually saving them to disk.

Usage

preview_webr_link(url)

Arguments

url

Character string containing the webR URL

Value

A webr_preview object, which is a list with these entries.

• url, the link that was read.

• mode, the panels the link asks for, or NULL for all of them.

• version, the webR version the link points at.

• flags, the encoding flags read off the link.

• files_data, a list with one entry per embedded file, each holding the file's name, its path inside webR, and its text.

• total_files, how many files the link carries.

• total_size, the size of those files in bytes.

• autorun_files, the names of the files that run as soon as the link opens.

Nothing is written to disk.

Details

Use print method options to control the display. The returned object's print() method accepts show_content and max_content_length to display file bodies.

See also

decode_webr_link() to extract the embedded files to disk once you are happy with the preview.

Examples

url <- as.character(webr_repl_link("plot(1:10)"))

# Inspect a link without writing anything to disk
preview <- preview_webr_link(url)

# Default print (no content)
print(preview)
#> 
#> ── webR Link Preview ──
#> 
#> URL:
#> <https://webr.r-wasm.org/latest/#code=eJyb2LwkLzE3dUVxclFmQYle0JKCxJKM7foZ%2Bbmp%2BuWpSfGlxalF%2BnDJktSKklUFOfklGoZWhgaaAC8DGLU%3D&mz>
#> 
#> Files: 1
#> Total size: 10 bytes
#> Version: "latest"
#> Encoding: "mz"
#> 
#> script.R (10 bytes)
#> 
#> Use print(preview, show_content = TRUE) to see file contents

# Show file contents
print(preview, show_content = TRUE)
#> 
#> ── webR Link Preview ──
#> 
#> URL:
#> <https://webr.r-wasm.org/latest/#code=eJyb2LwkLzE3dUVxclFmQYle0JKCxJKM7foZ%2Bbmp%2BuWpSfGlxalF%2BnDJktSKklUFOfklGoZWhgaaAC8DGLU%3D&mz>
#> 
#> Files: 1
#> Total size: 10 bytes
#> Version: "latest"
#> Encoding: "mz"
#> 
#> script.R (10 bytes)
#>   plot(1:10)

# Show file contents with custom length limit
print(preview, show_content = TRUE, max_content_length = 200)
#> 
#> ── webR Link Preview ──
#> 
#> URL:
#> <https://webr.r-wasm.org/latest/#code=eJyb2LwkLzE3dUVxclFmQYle0JKCxJKM7foZ%2Bbmp%2BuWpSfGlxalF%2BnDJktSKklUFOfklGoZWhgaaAC8DGLU%3D&mz>
#> 
#> Files: 1
#> Total size: 10 bytes
#> Version: "latest"
#> Encoding: "mz"
#> 
#> script.R (10 bytes)
#>   plot(1:10)

# Access the preview data
preview$files_data
#> [[1]]
#> [[1]]$name
#> [1] "script.R"
#> 
#> [[1]]$path
#> [1] "/home/web_user/script.R"
#> 
#> [[1]]$text
#> [1] "plot(1:10)"
#> 
#> 
preview$total_files
#> [1] 1