wikijs-fork/server/modules/rendering/markdown-kroki/renderer.js
Regev Brody 77086a6e0a
feat: optional kroki/plantuml svg caching (#2047)
* feat: Caching kroki svgs #2020
2020-06-18 18:39:25 -04:00

144 lines
4.3 KiB
JavaScript

const zlib = require('zlib')
// ------------------------------------
// Markdown - Kroki Preprocessor
// ------------------------------------
module.exports = {
init (mdinst, conf) {
mdinst.use((md, opts) => {
const openMarker = opts.openMarker || '```kroki'
const openChar = openMarker.charCodeAt(0)
const closeMarker = opts.closeMarker || '```'
const closeChar = closeMarker.charCodeAt(0)
const server = opts.server || 'https://kroki.io'
md.block.ruler.before('fence', 'kroki', (state, startLine, endLine, silent) => {
let nextLine
let markup
let params
let token
let i
let autoClosed = false
let start = state.bMarks[startLine] + state.tShift[startLine]
let max = state.eMarks[startLine]
// Check out the first character quickly,
// this should filter out most of non-uml blocks
//
if (openChar !== state.src.charCodeAt(start)) { return false }
// Check out the rest of the marker string
//
for (i = 0; i < openMarker.length; ++i) {
if (openMarker[i] !== state.src[start + i]) { return false }
}
markup = state.src.slice(start, start + i)
params = state.src.slice(start + i, max)
// Since start is found, we can report success here in validation mode
//
if (silent) { return true }
// Search for the end of the block
//
nextLine = startLine
for (;;) {
nextLine++
if (nextLine >= endLine) {
// unclosed block should be autoclosed by end of document.
// also block seems to be autoclosed by end of parent
break
}
start = state.bMarks[nextLine] + state.tShift[nextLine]
max = state.eMarks[nextLine]
if (start < max && state.sCount[nextLine] < state.blkIndent) {
// non-empty line with negative indent should stop the list:
// - ```
// test
break
}
if (closeChar !== state.src.charCodeAt(start)) {
// didn't find the closing fence
continue
}
if (state.sCount[nextLine] > state.sCount[startLine]) {
// closing fence should not be indented with respect of opening fence
continue
}
var closeMarkerMatched = true
for (i = 0; i < closeMarker.length; ++i) {
if (closeMarker[i] !== state.src[start + i]) {
closeMarkerMatched = false
break
}
}
if (!closeMarkerMatched) {
continue
}
// make sure tail has spaces only
if (state.skipSpaces(start + i) < max) {
continue
}
// found!
autoClosed = true
break
}
let contents = state.src
.split('\n')
.slice(startLine + 1, nextLine)
.join('\n')
// We generate a token list for the alt property, to mimic what the image parser does.
let altToken = []
// Remove leading space if any.
let alt = params ? params.slice(1) : 'uml diagram'
state.md.inline.parse(
alt,
state.md,
state.env,
altToken
)
let firstlf = contents.indexOf('\n')
if (firstlf === -1) firstlf = undefined
let diagramType = contents.substring(0, firstlf)
contents = contents.substring(firstlf + 1)
let result = zlib.deflateSync(contents).toString('base64').replace(/\+/g, '-').replace(/\//g, '_')
token = state.push('kroki', 'img', 0)
// alt is constructed from children. No point in populating it here.
token.attrs = [ [ 'src', `${server}/${diagramType}/svg/${result}` ], [ 'alt', '' ], ['class', 'uml-diagram prefetch-candidate'] ]
token.block = true
token.children = altToken
token.info = params
token.map = [ startLine, nextLine ]
token.markup = markup
state.line = nextLine + (autoClosed ? 1 : 0)
return true
}, {
alt: [ 'paragraph', 'reference', 'blockquote', 'list' ]
})
md.renderer.rules.kroki = md.renderer.rules.image
}, {
openMarker: conf.openMarker,
closeMarker: conf.closeMarker,
server: conf.server
})
}
}