free-programming-books-parser/index.js

360 lines
12 KiB
JavaScript

#!/usr/bin/env node
const fs = require("fs");
const path = require("path");
const remark = require("remark");
const languages = require("./languages");
const commandLineArgs = require("command-line-args");
const optionDefinitions = [
{
name: "input",
multiple: true,
defaultValue: ["./fpb/books", "./fpb/casts", "./fpb/courses", "./fpb/more"],
},
{ name: "output", defaultValue: "./parser/fpb.json" },
];
const excludes = [
"README.md",
"CONTRIBUTING.md",
"CODE_OF_CONDUCT.md",
"SUMMARY.md",
];
/**
* Parses a list item generated from remark-parse into a readable format.
*
* remark-parse parses a markdown file into a long, intricate json.
* Many fields in this json either give information we do not care
* about or does not go into enough detail. This function parses the
* output of remark-parse into a format preferred by this project,
* indicating authors, notes, and links etc.
*
* @param {Object} listItem - a listItem in AST format defined by remark-parse
*
* @return {Object} Returns an Object containing details about the piece of media.
*/
function parseListItem(listItem) {
let stripParens = function (s) {
if (s.slice(0, 1) === "(" && s.slice(-1) === ")") return s.slice(1, -1);
return s;
};
let entry = {};
let s = ""; // If we need to build up a string over multiple listItem elements
let leftParen,
rightParen = -1; // If we need to parse parenthesized text
const [link, ...otherStuff] = listItem; // head of listItem = url, the rest is "other stuff"
entry.url = link.url;
entry.title = link.children[0].value;
// remember to get OTHER STUFF!! remember there may be multiple links!
for (let i of otherStuff) {
if (s === "") {
// this is almost always, except for when we are parsing a multi-element note
if (i.type === "text" && i.value.slice(0, 3) === " - ") {
// author found
let parenIndex = i.value.indexOf("(");
if (parenIndex === -1) {
entry.author = i.value.slice(3).trim();
} else {
entry.author = i.value.slice(3, parenIndex).trim(); // go from " - " until the first "("
}
}
if (
i.type === "emphasis" &&
i.children[0].value.slice(0, 1) === "(" &&
i.children[0].value.slice(-1) === ")"
) {
// access notes found (currently assumes exactly one child, so far this is always the case)
entry.accessNotes = i.children[0].value.slice(1, -1);
}
if (i.type === "link") {
// other links found
if (entry.otherLinks === undefined) entry.otherLinks = [];
entry.otherLinks.push({
title: stripParens(i.children[0].value),
url: i.url,
});
// entry.otherLinks = [...entry.otherLinks, {title: i.children[0].value, url: i.url}]; // <-- i wish i could get this syntax to work with arrays
}
if (i.type === "text" && i.value.indexOf("(") !== -1) {
// notes found (currently assumes no nested parentheses)
if (entry.notes === undefined) entry.notes = [];
leftParen = i.value.indexOf("(");
while (leftParen != -1) {
rightParen = i.value.indexOf(")", leftParen);
if (rightParen === -1) {
// there must be some *emphasis* found
s += i.value.slice(leftParen);
break;
}
entry.notes.push(i.value.slice(leftParen + 1, rightParen));
leftParen = i.value.indexOf("(", rightParen);
}
}
} else {
// for now we assume that all previous ifs are mutually exclusive with this, may polish later
if (i.type === "emphasis") {
// this is the emphasis, add it in boldface and move on
s += "*" + i.children[0].value + "*";
} else if (i.type === "link") {
// something has gone terribly wrong. this book must be viewed and edited manually.
entry.manualReviewRequired = true;
break;
} else {
// hopefully this is the end of the note
let rightParen = i.value.indexOf(")");
if (rightParen === -1) {
// we have to go AGAIN
s += i.value;
} else {
// finally, we have reached the end of the note
entry.notes.push(stripParens(s + i.value.slice(0, rightParen + 1)));
s = "";
// this is a copypaste of another block of code. probably not a good thing tbh.
leftParen = i.value.indexOf("(");
while (leftParen != -1) {
rightParen = i.value.indexOf(")", leftParen);
if (rightParen === -1) {
// there must be some *emphasis* found
s += i.value.slice(leftParen);
break;
}
entry.notes.push(i.value.slice(leftParen + 1, rightParen));
leftParen = i.value.indexOf("(", rightParen);
}
}
}
}
}
return entry;
}
/**
* Determines the language a certain file is based on the format
* from the FreeEbookFoundation GitHub page
* @param {String} filename A filename in the format kept by all markdown files on the FreeProgrammingBooks Github
* @returns {String} The language the file is
*/
function getLangFromFilename(filename) {
const dash = filename.lastIndexOf("-");
const dot = filename.lastIndexOf(".");
let lang = filename.slice(dash + 1, dot).replace(/_/, "-");
let isSubject = false;
if (!languages.hasOwnProperty(lang)) {
if (/^[a-z]{2}$/.test(lang) || /^[a-z]{2}-[A-Z]{2}$/.test(lang)) {
return "";
}
// console.log(lang);
if (lang === "subjects") {
isSubject = true;
}
lang = "en";
}
return { lang: lang, isSubject: isSubject };
}
/**
* Gets all markdown files in a directory,
* @param {String} dir - A directory path
* @returns A list of all md files in a directory, excluding those in the excludes array
*/
function getFilesFromDir(dir) {
return fs
.readdirSync(dir)
.filter(
(file) => path.extname(file) === ".md" && excludes.indexOf(file) === -1
)
.map((file) => path.join(dir, file));
}
/**
* Retrieves the folder name from a string representing a directory and file
* @param {String} str - A string representing a path directory alike in the format "./directory/file"
* @returns {String} The extracted directory name
*/
function getMediaTypeFromDirectoryPath(str) {
const slash = str.lastIndexOf("/");
let mediaType = str.slice(2, slash);
return mediaType;
}
/**
* Turns a single markdown file into the json structure needed
* @param {path} doc - a single file path to a markdown file
* @returns {object} Json object of entries in the md file
*/
function parseMarkdown(doc) {
let tree = remark.parse(doc).children;
let sections = []; // This will go into root object later
let errors = [];
let currentDepth = 3; // used to determine if the last heading was an h4 or h3
// find where Index ends
// probably could be done better, review later
let i = 0,
count = 0;
for (i; i < tree.length; i++) {
if (tree[i].type == "heading" && tree[i].depth == "3") count++;
if (count == 2) break;
}
tree.slice(i).forEach((item) => {
// Start iterating after Index
try {
if (item.type == "heading" && item.children[0].value == "Index") return;
if (item.type == "heading") {
if (item.depth == 3) {
// Heading is an h3
currentDepth = 3;
let newSection = {
section: item.children[0].value, // Get the name of the section
entries: [],
subsections: [],
};
sections.push(newSection); // Push the section to the output array
} else if (item.depth == 4) {
// Heading is an h4
currentDepth = 4;
let newSubsection = {
section: item.children[0].value, // Get the name of the subsection
entries: [],
};
sections[sections.length - 1].subsections.push(newSubsection); // Add to subsection array of most recent h3
}
} else if (item.type == "list") {
item.children.forEach((listItem) => {
let content = listItem.children[0].children; // gets array containing a remark-link and a remark-paragraph
// if(content[0].type !== 'link'){ // SKIPS OVER bad formatting
// return;
// }
if (currentDepth == 3) {
let contentJson = parseListItem(content);
sections[sections.length - 1].entries.push(contentJson); // add the entry to most recent h3
} else if (currentDepth == 4) {
let lastSection = sections.length - 1;
let lastSubSec = sections[lastSection].subsections.length - 1;
let contentJson = parseListItem(content);
sections[lastSection].subsections[lastSubSec].entries.push(
contentJson
); // add entry to most recent h4
}
});
}
} catch (e) {
// if there was an error while parsing, print the error to an error log
// looks really ugly, maybe try to refine output later
let errStart = JSON.stringify(item.position.start.line);
let errEnd = JSON.stringify(item.position.end.line);
str = `Error at line ${errStart} - line ${errEnd}.`;
errors.push(str);
}
});
return { sections: sections, errors: errors };
}
/**
* Parses a single directory's md files and converts them into usable json
* @param {String} directory A string pointing to a directory
* @returns {Object} An object containing two values, dirJson and dirErrors.
* dirJson contains all data that was successfully parsed from
* the markdown files. dirErrors contains all entries that had
* an error occur while parsing.
*/
function parseDirectory(directory) {
let dirChildren = []; // this will hold the output each markdown doc
let dirErrors = []; //contains error for a given directory
let mediaType = getMediaTypeFromDirectoryPath(directory);
const filenames = getFilesFromDir(path.resolve(directory));
filenames.forEach((filename) => {
const doc = fs.readFileSync(filename);
let { sections, errors } = parseMarkdown(doc); // parse the markdown document
const { lang, isSubject } = getLangFromFilename(filename);
// Entries
let docJson = {
language: {
code: lang,
name: languages[lang],
},
index: {},
sections: sections,
};
if (lang === "en") docJson.language.isSubject = isSubject;
dirChildren.push(docJson);
// Errors
if (errors.length !== 0) {
let docErrors = {
file: path.basename(filename),
errors: errors,
};
dirErrors.push(docErrors);
}
});
// File entries
let dirJson = {
type: mediaType,
index: {},
children: dirChildren,
};
// Errors
return { dirJson: dirJson, dirErrors: dirErrors };
}
/**
* Reads all given directories for markdown files and prints the parsed json in the output directory
*
* @param {Array} directories A list of strings of directories to scan for markdown files
* @param {String} output A string for the path that the output should be placed in
*/
function parseAll(directories, output) {
let rootChildren = []; // this will hold the output of each directory
let rootErrors = [];
directories.forEach((directory) => {
let { dirJson, dirErrors } = parseDirectory(directory);
rootChildren.push(dirJson);
if (dirErrors.length !== 0) {
rootErrors.push({
directory: path.basename(directory),
files: dirErrors,
});
}
});
// ALl entries
let rootJson = {
type: "root",
children: rootChildren,
};
// Errors
let allErrors = {
type: "root",
directories: rootErrors,
};
fs.writeFileSync(output, JSON.stringify(rootJson, null, 3), function (err) {
if (err) {
console.log(err);
}
});
// fs.writeFileSync(
// "./parser/fpb.log",
// JSON.stringify(allErrors, null, 3),
// function (err) {
// if (err) {
// console.log(err);
// }
// }
// );
}
let { input, output } = commandLineArgs(optionDefinitions);
parseAll(input, output);