How does an AWS S3 POST object form initiate an upload - amazon-s3

I’m uploading images from a user’s device to a S3 bucket using POST object from a HTML form. Everything is working fine but I don’t understand how the S3 server can initiate an upload from a client browser after the form data (file name, signature, policy, etc.) has been posted to its URL. The image data is in a file on the client device and is not contained in the form, only the file name is there. Where in the process is the upload started and how does the S3 server tell the client browser to upload the image data? Perhaps there’s more communication between the web server and browser during a post/response that I’m not aware of. Any insight would be appreciated.

Further research has shown that the browser itself automatically formats each file as a part of the form submission when the form has an input type="file" control. The file becomes an intrinsic part of the form data submitted and the server side processing knows to look for it as such.
HTML4 input type="file" spec
"The following example shows how the contents of a user-specified file may be submitted with a form. The user is prompted for his or her name and a list of file names whose contents should be submitted with the form. By specifying the enctype value of "multipart/form-data", each file's contents will be packaged for submission in a separate section of a multipart document."

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Can't send a binary attachment to Slack using LogicApp

I'm trying to use a logicapp to get the content of an email and post it to slack. By content I mean:
the body of the email and other elements like From:, Subject:
any attachment in the email (which usually are binary like PDF, Excel, image)
the email itself saved in a blob as .eml file
Slack chat.postMessage API works without any problem to send any text element. This API has some attachment argument but doesn't seemto be designed or binary files (or not for files at all, only strings)
I've tried slack files.upload one but couldn't figure out the syntax, especially the syntax using a regular HTTP POST. Could find examples online using curl, Python, JS and C# SDK but I don't know how to translate them to HTTP POST just like I do with chat.PostMessage
I've tried the API on SOAP UI, using file as argument as per the documentation, and I've used it in different sections: in the header, in the body, and using the Attachment Tab, none of the work and always the same error message : no_file_data
Unfortuatelly slack documentation lacks of details. Here's what it says about files.upload:
You must provide either a file or content parameter.
The content of the file can either be posted using an enctype of multipart/form-data (with the file parameter named file), in the usual way that files are uploaded via the browser, or the content of the file can be sent as a POST var called content. The latter should be used for creating a "file" from a long message/paste and forces "editable" mode.
In both cases, the type of data in the file will be intuited from the
filename and the magic bytes in the file, for supported formats.
I could use alternatives like just saving the attachments in blobs and use Azure functions to send the file, but I want to understand what's the limitations before changing the method.
Any clue?

Build a flow using Power Automate to download a CSV file via a link in email and upload the file to Google Drive

I am completely new to Power Automate and have seen similar questions and posts about this topic, but most are addressed by inserting an HTML step at the end, which means it requires a paid version of Power Automate. I'm wondering if it's possible to build a flow with the free version.
If not, I'm also wondering if anyone has ideas on addressing my issue. I receive a CSV report via a URL in the email that sending from Google Ads every day. After I click the "view report" button, it directs me to a webpage and downloads a CSV file automatically. Eventually, I want to download the report and upload it to my Google drive.
I'm attaching the screenshot of the email content if it helps:
Power Automate Flow
HTML to text content
Initialization variable:
Name: startIndex
Type: Integer
indexOf(outputs('Html_to_text')?['body'],'VIEW REPORT')
Initialization variable2:
Name: endIndex
Type: Integer
add(indexOf(outputs('Html_to_text')?['body'],'Learn'),6)
Initialization variable:
Name: url
Type: String
substring(outputs('Html_to_text')?['body'],variables('startIndex'),sub(variables('endIndex'),variables('startIndex')))
Current output in plain text:
VIEW REPORT
[https://urldefense.com/v3/https://notifications.google.com/g/p/AD-FnEz5EAv3CG8aF4CNNPTSIlfZcRG3FiDbia5D0gDCbGwjg0TEhpi3mu5v36iTQxQV0vEUa9-y8NSJNJ8NZFN3HTw9wXaUatKQNt2zVCy6b_8WEfl18LisbGN-N45qaQlRQLNlXIaaeoeN7y2ryAni3ewe9RF1LgBaUwVeV184HMAT3wV6Wazp6m4K9EFNXJMubGCgsiR4bKsSjHYT1n0GUP922CyEqHvuieXoOJcg_zxAajq6NJ8mLrGFpXNzbzuf-Rkxt7K6U41i2sv23k8NjbyJggZzjmYlDCJxMi0Yfrhtp9nv4tHHWHYhmFoDrGlCUBpLIlU1OejCAAPh5b528dfwLEnuJiPZD2jbzSqi2xc0pni5azu6X5ovfYwwt1tOEhE6WMh-skqEAKPZsojJXlsR_1wEo6rjIzkZSPH1PlHZ6hOEf9NSIRsFyOSltCzFMciuSwZ2W9ElpCHJHY7HFtbscgtyCYkwIGF0ul5ZFd1X2TU10n-mNspwbm-nIYnVLU9lkAYwo7hLuIXk0jEYeB_5oBRht8dVRcdxtTe_hdAlP1V6fe5XPiAP7iKMKI1LecsdKdatHhY-Rpfj0ug;!!MOA0!LtG7zavxLCLQxJx_IASs8WS58E9Vyh6h007Aak8KErrQEibrffJ-7nMH43ah2***z9lJsRE$]
Learn
You can't do this with free connectors but this can be achieved via HTTP connector which is a premium connector.
Coming to you situation, i am assuming that you are able to get the actual csv file url (sometimes another url redirect you to actual file url).
Now you simply need to make an HTTP call from Power Automate flow and then create file using OneDrive for Business connector. See my code below, i have used a publicly available csv file to download and i am saving it to a folder in OneDrive directly.

How to streamline an SSRS web service call?

Using a 3rd party application (Tenfold) I currently call the SSRS web service methods to render a report as .pdf.
After I receive the encoded blob (5th parameter in the Render Method) I write the blob to the file system as a pdf using an internal WriteBinaryFile call, but in this form I cannot open it in a pdf reader. To solve this problem we write a .txt file with the path and file name of the pdf. Then send that to an external program Base64Decoder.exe which converts the file to a user friendly form that I can then open and view properly.
The Base64Decoder.exe is not 100% reliable and I'm looking for a better way to solve this problem. From what I've read from others the web service should return the blob in binary form which I then should be able to open without any conversion. Thanks in advance for any light that you can shed on this issue for me.
the render method returns a byte array, which is what you want to save to disk
there's an example here:
http://technet.microsoft.com/en-us/library/aa258532(v=sql.80).aspx

No signature in HelloSign signed document

I have this strange question regarding HelloSign, the answer to witch I was not able to find in their docs.
I have implemented the embed signing feature on my website with test mode on.
The signing process goes as it should via POST /signature_request/create_embedded request. The iFrame is opened, I put the signature and after I get the SIGNED event, I perform the GET /signature_request/files/[:signature_request_id] request to get signed document. The file is being downloaded and saved, and when I open it and compare with the file preview I have on HelloSign account, I see the many differences.
In my downloaded file there is the signature field added by HelloSign, but actually there is no signature inside. Also the additional page with transaction information does not exist.
Here is actually what I get in my pdf:
And this is what is contained in the file downloaded directly from HS admin:
Does this mean there was something wrong with downloaded doc, or is this just the test mode effect?
I hope I haven't completely misunderstood the signing feature...
You should be waiting for the backend callback with the event signature_request_all_signed.
More info on handling callbacks can be found here: https://www.hellosign.com/api/eventsAndCallbacksWalkthrough
When a user signs a document, it takes a few seconds for the final PDF to be generated. If you request to download the file before then, you will get the file in the state before it is signed (i.e. in the same state as if you had downloaded the file before the user had signed). To be safe, wait for the signature_request_all_signed callback and then fetch the final PDF.

How can I start using content of a Drive file before it is fully downloaded?

Am created one apps for ipad.. its already have view part.. In that am integrated google drive for list files. After listing when the user clicks to view files its going to download and then viewed by user.
Upto complete download user cant open the book. If that file content too large it takes too much time. Is it there any other way when user click file to open instantly.. or it shows 2 or 3 pages first after that remaining pages loads in background.
You have 2 choices. For instance you could download the content pieces by pieces using the Range HTTP header. The other possibility is to stream the response object (in Java I would do that by reading bytes in the InputStream of the response as they come). Too bad my lack of Objective-C skills don't allow me to help you further.