Overview

The lib microservice is a simplified file manager which serves files from local file system or public git repositories. It is possible to

• Upload and download files from web browser
• Query available files and download them using GraphQL API
• Clone public git repositories and serve them as local files

:arrow_down: Install

Default NPM Registry

The default registry for npm packages is npmjs. Install the package with the following commands

npm install -g @into-cps-association/libms

Github NPM Registry

The package is also available in Github packages registry.

Set the registry and install the package with the following commands

npm config set @into-cps-association:registry https://npm.pkg.github.com
npm install -g @into-cps-association/libms

The npm install command asks for username and password. The username is your Github username and the password is your Github personal access token. In order for the npm to download the package, your personal access token needs to have read:packages scope.

:gear: Configure

The microservices requires config specified in yaml format. The template configuration file is:

port: '4001'
mode: 'local'    #git or local
local-path: '..\..\files'
log-level: 'debug'
apollo-path: '/lib'
graphql-playground: 'true'

git-repos:   #only used in git mode
  - user1: 
      repo-url: 'https://gitlab.com/dtaas/user1.git'
  - user2: 
      repo-url: 'https://gitlab.com/dtaas/user2.git'
  - common: 
      repo-url: 'https://gitlab.com/dtaas/common.git'

The local-path variable is the relative filepath to the location of the local directory which will be served to users by the Library microservice.

Replace the default values the appropriate values for your setup. Please save this config in a file as a yaml file, for example as libms.yaml.

Operation Modes

The mode indicates the backend storage for the files. There are two possible modes - local and git. The files available in the local-path are served to users in local mode. In the git mode, the remote git repos are cloned and they are served to users as local files.

git mode

A fragment of the config for git mode is:

...
git-repos:
  - user1: 
      repo-url: 'https://gitlab.com/dtaas/user1.git'
  - user2: 
      repo-url: 'https://gitlab.com/dtaas/user2.git'
  - common: 
      repo-url: 'https://gitlab.com/dtaas/common.git'

Here, user1, user2 and common are the local directories into which the remote git repositories get cloned. The name of the repository need not match with the local directory name. For example, the above configuration enables library microservice to clone https://gitlab.com/dtaas/user1.git repository into user1 directory. Any git server accessible over HTTP(S) protocol is supported. The .git suffix is optional.

:rocket: Use

Display help.

$libms -h
Usage: libms [options]

The lib microservice is a file server. It supports file transfer
over GraphQL and HTTP protocols.

Options:
  -c, --config <file>  provide the config file (default libms.yaml)
  -H, --http <file>    enable the HTTP server with the specified config
  -h, --help           display help for libms

Both the options are not mandatory.

Configuration file

The config is saved libms.yaml file by convention. If -c is not specified The libms looks for libms.yaml file in the working directory from which it is run. If you want to run libms without explicitly specifying the configuration file, run

libms

To run libms with a custom config file,

libms -c FILE-PATH
libms --config FILE-PATH

If the environment file is named something other than libms.yaml, for example as config/libms.yaml.default, you can run

libms -c "config/libms.yaml.default"

You can press Ctl+C to halt the application.

Protocol Support

The libms supports GraphQL protocol by default. It is possible to enable the HTTP protocol by setting the -H option.

To run libms with a custom config for HTTP protocol, use

libms -H FILE-PATH
libms --http FILE-PATH

{
  "name": "DTaaS Fileserver",
  "auth": false,
  "editor": "edward",
  "packer": "zip",
  "diff": true,
  "zip": true,
  "buffer": true,
  "dirStorage": true,
  "online": false,
  "open": false,
  "oneFilePanel": true,
  "keysPanel": false,
  "prefix": "/lib/files",
  "confirmCopy": true,
  "confirmMove": true,
  "showConfig": false,
  "showDotFiles": false,
  "showFileName": true,
  "contact": false,
  "configDialog": false,
  "console": false,
  "terminal": false,
  "vim": false,
  "columns": "name-size-date-owner-mode",
  "export": false,
  "import": false,
  "dropbox": false,
  "dropboxToken": "",
  "log": true
}

Application Programming Interface (API)

The lib microservice application provides services at two end points:

HTTP protocol

Endpoint: localhost:PORT/lib/files

This option needs to be enabled with -H http.json flag. The regular file upload and download options become available.

GraphQL protocol

Endpoint: localhost:PORT/lib

Directory Listing

This query receives directory path and provides list of files in that directory. A sample query and response are given here.

query {
  listDirectory(path: "user1") {
    repository {
      tree {
        blobs {
          edges {
            node {
              name
              type
            }
          }
        }
        trees {
          edges {
            node {
              name
              type
            }
          }
        }
      }
    }
  }
}

{
  "data": {
    "listDirectory": {
      "repository": {
        "tree": {
          "blobs": {
            "edges": []
          },
          "trees": {
            "edges": [
              {
                "node": {
                  "name": "common",
                  "type": "tree"
                }
              },
              {
                "node": {
                  "name": "data",
                  "type": "tree"
                }
              },
              {
                "node": {
                  "name": "digital twins",
                  "type": "tree"
                }
              },
              {
                "node": {
                  "name": "functions",
                  "type": "tree"
                }
              },
              {
                "node": {
                  "name": "models",
                  "type": "tree"
                }
              },
              {
                "node": {
                  "name": "tools",
                  "type": "tree"
                }
              }
            ]
          }
        }
      }
    }
  }
}

Fetch a File

This query receives directory path and send the file contents to user in response.

To check this query, create a file files/user2/data/welcome.txt with content of hello world.

A sample query and response are given here.

query {
  readFile(path: "user2/data/sample.txt") {
    repository {
      blobs {
        nodes {
          name
          rawBlob
          rawTextBlob
        }
      }
    }
  }
}

{
  "data": {
    "readFile": {
      "repository": {
        "blobs": {
          "nodes": [
            {
              "name": "sample.txt",
              "rawBlob": "hello world",
              "rawTextBlob": "hello world"
            }
          ]
        }
      }
    }
  }
}

Direct HTTP API Calls in lieu of GraphQL API Calls

The lib microservice also supports making API calls using HTTP POST requests. Simply send a POST request to the URL endpoint with the GraphQL query in the request body. Make sure to set the Content-Type header to "application/json".

The easiest way to perform HTTP requests is to use HTTPie desktop application. You can download the Ubuntu AppImage and run it. Select the following options:

Method: POST
URL: localhost:4001
Body: <<copy the json code from examples below>>
Content Type: text/json

Here are examples of the HTTP requests and responses for the HTTP API calls.

Directory listing

POST /lib HTTP/1.1
Host: localhost:4001
Content-Type: application/json
Content-Length: 388

{
   "query":"query {\n  listDirectory(path: \"user1\") {\n    repository {\n      tree {\n        blobs {\n          edges {\n            node {\n              name\n              type\n            }\n          }\n        }\n        trees {\n          edges {\n            node {\n              name\n              type\n            }\n          }\n        }\n      }\n    }\n  }\n}"
}

This HTTP POST request will generate the following HTTP response message.

HTTP/1.1 200 OK
Access-Control-Allow-Origin: *
Connection: close
Content-Length: 306
Content-Type: application/json; charset=utf-8
Date: Tue, 26 Sep 2023 20:26:49 GMT
X-Powered-By: Express

{"data":{"listDirectory":{"repository":{"tree":{"blobs":{"edges":[]},"trees":{"edges":[{"node":{"name":"data","type":"tree"}},{"node":{"name":"digital twins","type":"tree"}},{"node":{"name":"functions","type":"tree"}},{"node":{"name":"models","type":"tree"}},{"node":{"name":"tools","type":"tree"}}]}}}}}}

Fetch a file

This query receives directory path and send the file contents to user in response.

To check this query, create a file files/user2/data/welcome.txt with content of hello world.

POST /lib HTTP/1.1
Host: localhost:4001
Content-Type: application/json
Content-Length: 217

{
   "query":"query {\n  readFile(path: \"user2/data/welcome.txt\") {\n    repository {\n      blobs {\n        nodes {\n          name\n          rawBlob\n          rawTextBlob\n        }\n      }\n    }\n  }\n}"
}

HTTP/1.1 200 OK
Access-Control-Allow-Origin: *
Connection: close
Content-Length: 134
Content-Type: application/json; charset=utf-8
Date: Wed, 27 Sep 2023 09:17:18 GMT
X-Powered-By: Express

{"data":{"readFile":{"repository":{"blobs":{"nodes":[{"name":"welcome.txt","rawBlob":"hello world","rawTextBlob":"hello world"}]}}}}}