3.1.3 SUBMOD.001.003 : Get AML File by id

Contents

• Changelog
• 1. Scope
• 2. Definitions
• 3. Module Requirements
  • 3.1 User view
  • 3.2 Requirements
  • 3.3 Module Context
• 4. Analysis
• 5. Design
  • 5.1 Risks
• 6. Implementation
  • 6.1 Get document by _id from database
  • 6.2 Response data
  • 6.3 Response download
• 7. Module Test
• 8. Summary
• 9. Appendix
  • 9.1 References
  • 9.2 Sourcecode

Changelog

Version	Date	Author	Comment
0.1	17.01.2021	Namid Marxen und Nils-Christopher Wiesenauer	created

1. Scope

The Module Documentations (MODs) describes the architecture, the interfaces and the main features of the module. It also describes the module/component test including the results. It can also serve as a programming or integration manual for the module. If there are some risks related to the module itself, they shall be noted and commented within this document.

2. Definitions

AML: Automation Markup Language

CRUD: Create Read Update Delete

GUI: Graphical User Interface

JSend: A specification that lays down some rules for how JSON responses from web servers should be formatted

SAS: System Architecture Specification

SRS: System Requirements Specification

3 Module requirements

This submodule contains the enpoint for getting one AML file by an ID.

This REST API is the most important module because it contains the logic for converting the AML file to JSON. It also includes the authorization to the database. When a file is uploaded to the server it is converted from an AML format to a JSON format so that it can be saved in the MongoDB database. The content of the files are saved as a string and then converted into one JSON object, so that each file has their own database entry, with the JSON object as the content.

3.1 User view

In order for the user to display a specific AML file, the REST API needs to have the functionality to return one AML file with a given ID. This is needed when the user wants to edit a file. Before editing, the content of the saved file needs to be put in a dialog. This content is provide by this submodule.

3.2 Requirements

The requirement for this submodule is in part LF70, because this submodule is needed in order for the user to get file he wants to edit. When the user clicks on a file in the list of files he wants to edit, a dialogue with the content of the file is opened in the GUI. This content is gathered by this submodule.

3.3 Module Context

The submodule to get an AML file by id provides the functionality to get a file by id. This function is needed when the user wants to edit a specific AML file. He opens the file and gives an id from the GUI.

4. Analysis

This function is required to give the user the ability to edit files. The function provides the interface between GUI and database in order to edit saved files. This function is part of the edit file submodule.

5. Design

We included all /file routes into our server.js where the FILE schema is imported to have every enpoint together and clear.

5.1 Risks

When this submodule is not available anymore, the user can no longer edit saved files. So this submodule is an essential part of the editing saved files.

6. Implementation

6.1 Get document by _id from database

The needed /file/:id and /file/:id/download GET endpoints are defined below. Here we are using the created FILE model to get a file document by _id from MongoDB by using ´FILE.getFile(_id, callback)´.

const FILE = require('./models/file');
...
app.get('/file/:id', (req, res) => {
  FILE.getFile(req.params.id, (err, file) => {
    >> 6.2 Response data
  });
});

app.get(`/file/:id/download`, (req, res) => {
  FILE.getFile(req.params.id, (err, file) => {
    >> 6.3 Response download
  });
});
...

6.2 Response data

After finding of our document we need to check if there is no error. If an error ocurred, we are sending a JSend with status 'error' and a defined message back. If everything was correct and a file could we found, we are modifying our base64 to ASCII. That because we need ASCII to modify our content of the file.

...
if (!err && file) {
  let newObj = {name: file.name, content: Buffer(file.base64, 'base64').toString('ascii')}
  res.status(200).send({ status: 'success', data: newObj });
} else {
  res.status(200).send({ status: 'error', message: 'Unable to get file' });
}
...

6.3 Response download

After finding of our document we need to check if there is no error. If an error ocurred, we are sending a JSend with status 'error' and a defined message back. If everything was correct and a file could we found, we are sending it as a JSend with status 'success' back.

...
if (!err && file) {
  res.status(200).send({status: 'success', data: file});
} else {
  res.status(200).send({status: 'error', message: 'Unable to download file'});
}
...

7. Module Test

8. Summary

The endpoint/submodule to get an AML file by an ID is neccessary to provide the user with the ability to get the content of a specific file. It is triggered by a request from the GUI when the user presses the edit button on a specific file. The request is processed by the REST API and another request is sent to the database. The response of the database is sent back to the user via JSend. The recieved content is then shown in a dialog where he can edit the file.

The implementation of the module is descriped with SwaggerUI.

9. Appendix

9.1 References

1. SRS (System Requirements Specification)
2. SAS (System Architecuture Specification)
3. Systemtestplan

9.2 Sourcecode

The source code of this module can be found here: aml-database-management-api/server.js