zord-tree/README.md

# zord-tree

[![Build Status](https://drone.arns.lt/api/badges/zordsdavini/zord-tree/status.svg)](https://drone.arns.lt/zordsdavini/zord-tree)

Library for golang to build articles tree from file system. The file should be in specific format to hold meta data, id and
content.

Process should go in two steps:

* populate existing `source` directory with formatting files, add missing `id` and meta data
* build `Tree` to operate on object for your app
* read file content without meta data by path


## File and tree format

### Category

During building `Tree` directory path is converted into array of categories. So, file in path `linux/command/video` will get
categories: `linux`, `command`, `video`.

### Split line

File meta should be split by `---` line. If there is markdown formating to mark header, first such case (`---`) will be formatted
to contain empty line. Example:

```
Text
---
```

will become

```
Text

---
```

### Meta data

Meta data separated by lines and in format `* name: value`. By default library supports `tags` as comma separated array.
During populating tree it adds missing `id` in `abcex` format and empty meta data lines and saves in `source` directory then copy
to `destination` directory.

There is possibility to add custom default value. That is passed with custom function what returns string.

### File structure

```
* tags: linux,command,video
* meta1: example
* meta2: some long description

---

Hear goes content. It can be written in html, markdown or whatever what can be processed later
```


## Usage

There are two main commands: `PopulateTree` to prepare source (format, add metadata and add Id) and copy from source to destination and `BuildTree` to get object of tree.

`Tree` object has methods: `FileById` to get `File` by Id, `Slice` to get sub-tree of given path and `Filter` to filter tree by filter.
Filter contains array of meta key and searching value. `tag` key is searched as equal and other meta values of keys can contain part.