Contributing
December 4, 2025 · View on GitHub
This guide have some instructions and tips on how to create a new IReader extension. Please read it carefully if you're a new contributor or don't have any experience on the required languages and knowledges.
This guide is not definitive and it's being updated over time. If you find any issue on it, feel free to report it through a Meta Issue or fixing it directly by submitting a Pull Request.
Table of Contents
- Prerequisites
- Getting help
- Writing an extension
- Writing an Multisrc Extension
- Running
- Building
- Submitting the changes
Prerequisites
Before you start, please note that the ability to use following technologies is required and that existing contributors will not actively teach them to you.
- Basic Android development
- Kotlin
- Web scraping
Tools
- Android Studio
- Emulator or phone with developer options enabled and a recent version of IReader installed
- Icon Generator
Cloning the repository
Some alternative steps can be followed to ignore "repo" branch and skip unrelated sources, which will make it faster to pull, navigate and build. This will also reduce disk usage and network traffic.
Steps
-
Make sure to delete "repo" branch in your fork. You may also want to disable Actions in the repo settings.
Also make sure you are using the latest version of Git as many commands used here are pretty new.
-
Do a partial clone.
git clone --filter=blob:none --sparse <fork-repo-url> cd IReader-extensions/
Getting help
- Join the Discord server for online help and to ask questions while developing your extension. When doing so, please ask it in the
#app-devchannel. - There are some features and tricks that are not explored in this document. Refer to existing extension code for examples.
Writing an extension
The quickest way to get started is to copy an existing extension's folder structure and renaming it as needed. We also recommend reading through a few existing extensions' code before you start.
Setting up a new Gradle module
Each extension should reside in sources/<lang>/<mysourcename>. Use sources/multisrc if your target source supports multiple languages or if it could support multiple sources.
The <lang> used in the folder inside src should be the major language part. For example, if you will be creating a pt-BR source, use <lang> here as pt only. Inside the source class, use the full locale string instead.
Extension file structure
The simplest extension structure looks like this:
$ tree src/<lang>/<mysourcename>/
sources/<lang>/<mysourcename>/
├── build.gradle
├── res (option 1)
│ ├── mipmap-hdpi
│ │ └── ic_launcher.png
│ ├── mipmap-mdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xhdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xxhdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xxxhdpi
│ │ └── ic_launcher.png
│ └── web_hi_res_512.png
└── main
└── assets (option 2)
└── icon.png
└── src
└── ireader
└── <mysourcename>
└── <MySourceName>.kt
build.gradle
Make sure that your new extension's build.gradle file follows the following structure:
listOf("en").map { lang ->
Extension(
name = "BoxNovelCom", // no space between letters
versionCode = 4,
libVersion = "2",
lang = lang,
description = "",
nsfw = false,
icon = DEFAULT_ICON // if you want to use a remote image repalce `DEFAULT_ICON` with a link
)
}.also(::register)
| Field | Description |
|---|---|
name | The name of the extension. |
versionCode | The extension version code. This must be a positive integer and incremented with any change to the code. |
libVersion | (Optional, defaults to 1) The version of the extensions library used. |
lang | the language of extension |
description | the description of extension that you want the users see in the app |
isNsfw | (Optional, defaults to false) Flag to indicate that a source contains NSFW content. |
icon | default to DEFAULT_ICON ,if you want to use a remote image repalce DEFAULT_ICON with a link |
sourceDir | default to main for a single extension |
assetsDir | leave it blank if you you are using local res or if you are using a individual extension |
remoteDependencies | if you want a dependency that is not available IReader-extension projects |
The extension's version name is generated automatically by concatenating libVersion and versionCode. With the example used above, the version would be 1.4.
Core dependencies
Extension API
Extensions rely on extensions-lib, which provides some interfaces and stubs from the app for compilation purposes. The actual implementations can be found here. Referencing the actual implementation will help with understanding extensions' call flow.
Additional dependencies
If you find yourself needing additional functionality, you can add more dependencies to your build.gradle file.
Many of the dependencies from the main IReader app are exposed to extensions by default.
Note that several dependencies are already exposed to all extensions via Gradle version catalog. To view which are available view
libs.versions.tomlunder thegradlefolder
Notice that we're using compileOnly instead of implementation if the app already contains it. You could use implementation instead for a new dependency, or you prefer not to rely on whatever the main app has at the expense of app size.
Note that using compileOnly restricts you to versions that must be compatible with those used in the latest stable version of IReader.
Extension main class
This class should implement one of the Source implementations: HttpSource or ParsedHttpSource.
| Class | Description |
|---|---|
HttpSource | For online source, where requests are made using HTTP. |
SourceFactory | An Implementation of HttpSource that make source creation easier. |
Main class key variables
| Field | Description |
|---|---|
name | Name displayed in the "Sources" tab in IReader. |
baseUrl | Base URL of the source without any trailing slashes. |
lang | An ISO 639-1 compliant language code (two letters in lower case in most cases, but can also include the country/dialect part by using a simple dash character). |
id | Identifier of your source, automatically set in HttpSource. It should only be manually overriden if you need to copy an existing autogenerated ID. |
Extension call flow
getMangaList(sort: Listing?, page: Int)
a.k.a. the default request that app make
Book Search
- When the user searches inside the app,
getMangaListwill be called - if the filters contain a Filter.Title that has a query then the you need to search for a query
- If search functionality is not available, return
Observable.just(MangasPage(emptyList(), false))
- If search functionality is not available, return
getFilterListwill be called to get all filters and filter types.
val query = filters.findInstance<Filter.Title>()?.value
if (query != null) {
getBooks(query = query) // you need to implement this yourself
}
Filters
The search flow have support to filters that can be added to a FilterList inside the getFilterList method. When the user changes the filters' state, they will be passed to the searchRequest, and they can be iterated to create the request (by getting the filter.state value, where the type varies depending on the Filter used). You can check the filter types available here and in the table below.
| Filter | State type | Description |
|---|---|---|
Filter.Note | String | a note for how to use filters |
Filter.Select<V> | Int | A select control, similar to HTML's <select>. Only one item can be selected, and the state is the index of the selected one. |
Filter.Text | String | A text control, similar to HTML's <input type="text">. |
Filter.Check | Boolean | A checkbox control, similar to HTML's <input type="checkbox">. The state is true if it's checked. |
Filter.Group<V> | List<V> | A group of filters (preferentially of the same type). The state will be a List with all the states. |
Filter.Sort | Selection | A control for sorting, with support for the ordering. The state indicates which item index is selected and if the sorting is ascending. |
Book Details
- When user taps on a book,
getMangaDetailsandgetChapterListwill be called and the results will be cached. - remember to check for
commandsif you enable some commands. fetchChapterListis called to display the chapter list.- The list should be sorted descending by the source order.
Chapter
- After a chapter list for the book is fetched and the app is going to cache the data,
getChapterListwill be called. ChapterInfo.dateUploadis the UNIX Epoch time expressed in milliseconds.-
If you don't pass
ChapterInfo.dateUploadand leave it zero, the app will use the default date instead, but it's recommended to always fill it if it's available. -
To get the time in milliseconds from a date string, you can use a
SimpleDateFormatlike in the example below.private fun parseDate(dateStr: String): Long { return runCatching { DATE_FORMATTER.parse(dateStr)?.time } .getOrNull() ?: 0L } companion object { private val DATE_FORMATTER by lazy { SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.ENGLISH) } }Make sure you make the
SimpleDateFormata class constant or variable so it doesn't get recreated for every chapter. If you need to parse or format dates in manga description, create another instance sinceSimpleDateFormatis not thread-safe.
-
Chapter Pages
- When user opens a chapter,
getPageListwill be called and it will return a list ofPages. - you need to parse the html to get a list of
Pages, for a novel its a list ofText
Writing an Multisrc Extension
Sometimes you have a common extension that is used for many languages and only some part of it need to be changed in order to create another extension for another website, in this case, we can use MultiSrc directory in sources/multisrc
Multisrc Extension file structure
The simplest extension structure looks like this:
$ tree sources/multisrc/<mysourcename>/
sources/multisrc/<mysourcename>/
├── build.gradle
├── res (option 1)
│ ├── mipmap-hdpi
│ │ └── ic_launcher.png
│ ├── mipmap-mdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xhdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xxhdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xxxhdpi
│ │ └── ic_launcher.png
│ └── web_hi_res_512.png
└── main ( common code that is used for othersources)
│ ├── res (option 1)
│ │ ├── mipmap-hdpi
│ │ │ └── ic_launcher.png
│ │ ├── mipmap-mdpi
│ │ │ └── ic_launcher.png
│ │ ├── mipmap-xhdpi
│ │ │ └── ic_launcher.png
│ │ ├── mipmap-xxhdpi
│ │ │ └── ic_launcher.png
│ │ ├── mipmap-xxxhdpi
│ │ │ └── ic_launcher.png
│ │ └── web_hi_res_512.png
│ |
│ ├── assets (option 2)
│ └── icon.png
│ └── src
│ └── ireader
│ └── <mysourcename>
│ └── <MySourceName>.kt
├── res (option 1)
│ ├── mipmap-hdpi
│ │ └── ic_launcher.png
│ ├── mipmap-mdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xhdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xxhdpi
│ │ └── ic_launcher.png
│ ├── mipmap-xxxhdpi
│ │ └── ic_launcher.png
│ └── web_hi_res_512.png
└── SiteA ( common code that is used for othersources)
│ ├── res (option 1)
│ │ ├── mipmap-hdpi
│ │ │ └── ic_launcher.png
│ │ ├── mipmap-mdpi
│ │ │ └── ic_launcher.png
│ │ ├── mipmap-xhdpi
│ │ │ └── ic_launcher.png
│ │ ├── mipmap-xxhdpi
│ │ │ └── ic_launcher.png
│ │ ├── mipmap-xxxhdpi
│ │ │ └── ic_launcher.png
│ │ └── web_hi_res_512.png
│ |
│ ├── assets (option 2)
│ └── icon.png
│ └── src
│ └── ireader
│ └── <SiteAName>
│ └── <SiteAName>.kt
└── SiteB ( Site A )
| ├── res (option 1)
| │ ├── mipmap-hdpi
| │ │ └── ic_launcher.png
| │ ├── mipmap-mdpi
| │ │ └── ic_launcher.png
| │ ├── mipmap-xhdpi
| │ │ └── ic_launcher.png
| │ ├── mipmap-xxhdpi
| │ │ └── ic_launcher.png
| │ ├── mipmap-xxxhdpi
| │ │ └── ic_launcher.png
| │ └── web_hi_res_512.png
| |
| ├── assets (option 2)
| └── icon.png
└── src
└── ireader
└── <SiteBName>
└── <SiteBName>.kt
build.gradle
Make sure that your new extension's build.gradle file follows the following structure:
listOf(
Extension(
name = "SiteA",
versionCode = 1,
libVersion = "2",
lang = "en",
description = "",
nsfw = false,
icon = DEFAULT_ICON,
assetsDir = "multisrc/<mysourcename>/SiteA/assets",
sourceDir = "SiteA",
),
Extension(
name = "SiteB",
versionCode = 1,
libVersion = "2",
lang = "ar",
description = "",
nsfw = false,
icon = DEFAULT_ICON,
assetsDir = "multisrc/<mysourcename>/SiteB/assets",
sourceDir = "SiteB",
),
).also(::register)
Note: if you want to test your extension you must comment other extension in build.gradle.kts
Running
You can run it directly in android studio, after selecting it in Run/Debug Configuration
Building
APKs can be created in Android Studio via Build > Build Bundle(s) / APK(s) > Build APK(s) or Build > Generate Signed Bundle / APK.
Submitting the changes
When you feel confident about your changes, submit a new Pull Request so your code can be reviewed and merged if it's approved. We encourage following a GitHub Standard Fork & Pull Request Workflow and following the good practices of the workflow, such as not commiting directly to master: always create a new branch for your changes.
If you are more comfortable about using Git GUI-based tools, you can refer to this guide about the Git integration inside Android Studio, specifically the "How to Contribute to an to Existing Git Repository in Android Studio" section of the guide.
Please do test your changes by compiling it through Android Studio before submitting it. Also make sure to follow the PR checklist available in the PR body field when creating a new PR. As a reference, you can find it below.
Pull Request checklist
- Update
VersionCodevalue inbuild.gradlefor individual extensions - Add the
isNsfw = trueflag inbuild.gradlewhen appropriate - Explicitly kept the
idif a source's name or language were changed - Test the modifications by compiling and running the extension through Android Studio