# Lithium Micro-service for file storage and processing written in Go. ## Features - Image processing pipelines for various transformations - Web API for storing & retrieving files ## Requirements - [Go 1.17+](https://go.dev/) - [_Docker_](https://docs.docker.com/) (optional) ## Setup #### 1. Clone repository ```shell git clone git@gogs.informatik.hs-fulda.de:FabianVowie/Lithium.git ``` #### 2. Pull dependencies ```shell go get ``` #### 3. Build & start application ```shell go run . ``` **Run using [Docker](https://docs.docker.com/) container** ```shell docker run --rm -p 8000:8000 -v "$PWD":/usr/src/lithium -w /usr/src/lithium golang:1.17 go run . ``` ## Testing ```shell go test ./... ``` ### Run tests in verbose logging mode ```shell go test ./... -v ``` ### Run tests in [Docker](https://docs.docker.com/) container ```shell docker run --rm -v "$PWD":/usr/src/lithium -w /usr/src/lithium golang:1.17 go test ./... ``` ## Configuration Config options can be adjusted via the [`settings.json`](settings.json) file in the root directory. ```json { "endpoint": "0.0.0.0:8000", "token": "changeme", "rate_limiter": { "requests_per_minute": 20, "allowed_burst": 5 }, "storage_provider": { "type": 0, "base_path": "assets" } } ``` ## Rate Limiting By default, the rate limiting takes place on a per-route basis. When the limit for a specific route is hit, the response will return a status code `429: Too Many Requests`. | Headers | Explanation | | --------------------- | -------------------------------- | | X-Ratelimit-Limit | Allowed requests per minute | | X-Ratelimit-Remaining | Remaining requests | | X-Ratelimit-Reset | Seconds until requests replenish | ## API ### `GET` `/` Show application information. **Required headers**: ```shell Authorization: Bearer ``` **Example response**: ```json { "name": "Lithium", "version": "0.1.0" } ``` ### `GET` `/pipelines/{pipeline}` Show pipeline information. **Required headers**: ```shell Authorization: Bearer ``` **Example response**: ```json { "name": "example pipeline", "slug": "example", "type": 0, "remove_metadata": false, "steps": [ { "name": "resize image", "type": 0, "options": { "width": 1280, "height": 720, "upscale": false } } ], "output": { "format": "jpg", "quality": 90 } } ``` ## Pipelines The project uses a pipeline system defined by [JSON](https://en.wikipedia.org/wiki/JSON) files located in the [config](config) folder. Take a look at the [example pipeline configuration file](config/example.json). Available pipeline `type`s: `0` (Image), `1` (Video) ```json { "name": "example pipeline", "slug": "example", "type": 0, "removeMetadata": false, "steps": [], "output": {} } ``` ### Images pipeline The image pipeline offers the following additional output options. Available `format` types: `jpg` (or `jpeg`), `png`, `gif`, `tif` (or `tiff`) and `bmp` The `quality` field can contain any integer between 1 and 100. ```json { "output": { "format": "jpg", "quality": 90 } } ``` ### Available pipeline steps Each pipeline step consists of an optional `name`, a predefined `type` and configurable `options`. See the available options below for more information. ```json { "name": "step name", "type": 0, "options": {} } ``` #### Resizing images Resize an image by a given `width` and `height`. **Step definition**: ```json { "type": 0, "options": { "width": 1280, "height": 720 } } ``` #### Rotating images Rotate an image with a given `angle` in degrees. **Step definition**: ```json { "type": 1, "options": { "angle": 90.0 } } ``` #### Flipping images Flip an image with a given direction. Allowed values for the `direction` option are `"h"` (horizontal), `"v"` (vertical) **Step definition**: ```json { "type": 2, "options": { "direction": "h" } } ``` #### Grayscale Convert the colorspace of an image into grayscale. **Step definition**: ```json { "type": 3 } ``` #### Fit Scales down the image to fit the specified maximum width and height. **Step definition**: ```json { "type": 4, "options": { "height": 300, "width": 200 } } ``` #### Invert Invert image colors. **Step definition**: ```json { "type": 5 } ``` #### Blur Blur image using Gaussian functions. **Step definition**: ```json { "type": 6, "options": { "sigma": 50.0 } } ``` ## Authors - [Fabian Vowie](https://gogs.informatik.hs-fulda.de/FabianVowie) - [Roman Zipp](https://gogs.informatik.hs-fulda.de/roman.zipp)