i am creating a api service using nodejs and express and to parse multipart request i am using multerjs. I have to receive a pdf file from rest request and it is coming as multipart/form-data and to verify file type i am checking the file.minetype
Now the issue is if someone changes the file extension like from mp4 -> pdf it also changes the mimetype to pdf and the file is accepted as pdf so how do i sniff the mimetype for content is their any way to do without any new packages. I really need to do it without using any packages as it'll take a really long to get a new package to approved
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Is there any method to read the downloaded file content(not the file name) using node js? I'm getting my downloaded file content-disposition: attachment;filename=hello11.xlsx like this. I want provide the URI to my excel data extraction function. but couldn't figure out how to get the URI because my get Request returns nothing but a file downloaded to the browser.
I found a similar question but it's using java
Apollo Server 2.0 has the ability to receive file uploads as described in this blog post.
However, all the tutorials and blog posts I found only showed how to upload a file. Nobody demonstrated how to actually retrieve the file back to display it onscreen.
Does anybody know how to properly query the file contents for display onscreen?
Also, there's the possibility that maybe there is no way of querying a file and you have to build a separate rest endpoint to retrieve the contents?
Some thoughts:
I imagine the query to be something like
query {
fetchImage(id: 'someid')
}
with the respective server-side definition
type Query {
fetchImage(id : ID!): Upload //maybe also a custom type, but how do I include the actual file contents?
}
Hint: Upload is a scalar type that apollo-server automatically adds to your type definition. It is used for the upload so I imaging it also being usable for the download/query. Please read the blog post mentioned above for more information.
The response from a GraphQL service is always serialized as a JSON object. Technically, a format other than JSON could be used in serialization but in practice only JSON is used because it meets the serialization requirements in the spec. So, the only way to send a file through GraphQL would be to convert the file into some format that's JSON-compatible. For example, you could convert a Buffer to a byte array and send that as an array of integers. You would also have to send the appropriate mime type. It would be up to the client to convert the byte array back into a usable format on receiving the response.
If you go this route, you'd have to use your own scalar or object type -- the Upload scalar does not support serialization so it will throw if you try to use it as an output type (and it's not really suitable for this sort of thing anyway).
However, while doing this is technically possible, it's also inadvisable. Serializing a larger file could cause you to run out of memory since there's no way to stream data through GraphQL (the entire response has to be in memory before it can be sent). It's much better to serve the file statically (ideally using nginx instead of Node). If your API needs to refer to the file, it can then just return the file's path.
You can do this by installing express with apollo server.
apollo-server-express
Install above package and instantiate Express object with Apollo Server as explained in package docs.
Then set the static folder using express like this
app.use("/uploads", express.static("uploads")); //Server Static files over Http
uploads is my static folder & /uploads will server get request to that path
//Now I can access static files like this
http://localhost:4000/uploads/test.jpg
I'm trying to create a .zip file by passing the returned body of an HTTP GET request to SharePoint's Create File.
Body is:
{
"$content-type": "application/zip",
"$content": "UEsDBBQACA...="
}
Shouldn't this just work? The docs only define the Create File field as "Content of the file." but that's not super informative...
I believe I've done this before with a file that was application/pdf and it worked. Unfortunately, I can't find that Logic App (I think it may have been an experiment I've since deleted).
I should note that the Create File action does create a valid .zip file, in that it's not corrupt, but archive is empty. It's supposed to contain a single .csv file.
I tried decoding the Base64 content and it's definitely binary data.
Any idea where I'm going wrong?
I test with Postman and when I use the form-data way to POST the request, I found the .zip file couldn't be open. Then I check the Logic App run history and I find the problem is if just use the triggerbody() as the file content it will fail.
This is because the triggerbody() not just have the $content, so I change the expression to triggerBody()['$multipart'][0]['body'] then it works and the .zip file is full.
I want to know the File type using "file" command without downloading file from S3 in Nodejs.
so aim is to only hit the file , fire "File" command on it and retrieve it's output. How can I achieve this without downloading?
Why not use the NodeJS S3 SDK to get the file details. There is a method that returns the object metadata. You can check the object ContentType to know its file type. It is returned in the response json when you make a request for an object's metadata.
http://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/S3.html#headObject-property
In my Spring MVC 3.0 based application I am trying to test the file upload functionality with some validations.
In one validation I changed .exe(executable) file to .txt , and expecting that exe file shouldn't be uploaded in the system.But it gets uploaded.
I am checking content type of file but in this case once file extension is changed it's content types also gets changed from "application/octet-stream" to "text/plain".
I am testing on Firefox and Google Chrome. And At Controller level Uploaded file is being read using MultipartFile.
Is there any way by which I get the original content type of file in this case "application/octet-stream" ?
When we change the extension of the file before uploading it ..It depends on Operating System weather the MIME type will change or not. Moreover, it is the responsibility of the browser to find out the Mime Type and set into the request header which is being read in the controller.