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Best way to get a file's URL

I am making an iOS app that displays all of the images from a selected folder. To make caching the images easier and more efficient I'm using the SDWebImage Library. SDWebImage requires a URL and I'm currently using the getTemporaryLink function to get a link for each image in the folder. Is there a better way to get a URL? I'm concerned that the links expiring will cause issues.

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Greg-DB

That is the right way to get a direct link to a file using the API.

I'll be happy to pass along as feedback or feature requests though. What specifically would be more useful? Thanks in advance!

All comments

Greg-DB

That is the right way to get a direct link to a file using the API.

I'll be happy to pass along as feedback or feature requests though. What specifically would be more useful? Thanks in advance!

SianZeng

I've been trying to find a way to share an image url from dropbox so that I can use it in my newsletters. Something like what imgur does.

I tested it by copying a shared link from dropbox but it didn't work. Is there a way to share image url-s from dropbox. Since Dropbox hosts our images anyway wouldn't be so difficult I thought.

Greg-DB

SianZeng, can you elaborate on what didn't work? It sounds like you may want to use the options documented here:

https://help.dropbox.com/desktop-web/force-download

mikemalter

I may not be thinking about this correctly, so I'm open to alternatives. I need to generate a document that lists all of the files and folders off of a selected Dropbox folder. This I can do now with no issues. One additional requirement is that the list be hyperlinked so if someone clicks on a link, that document will open. I could have file hyperlinks for our desktop users, but what about mobile phone users? I'm thinking that I'll need URL's for that. So I need to know how to get URL's for selected files. However, one of the messages above talks about links expiring. Is there a way to get a permanant URL that can be stored in a document?

Thanks.

Greg-DB

@mikemalter It sounds like Dropbox shared links might be a good solution for your use case. They don't expire (though they can be manually revoked). You can create them programmatically using the API via /2/sharing/create_shared_link_with_settings (or a corresponding method if you're using an official SDK).

mikemalter

@Greg K., thanks for your answer. Of course I have a few more questions.

If our group's content manager set up shared folders, is that the same thing as shared files? Do we have to create a shared link to every file?
I looked at the Json code to create a shared link and I'm wondering can I do the same thing in C#? I have not coded anything in Json at this point.
I noticed that there did not seem to be anyway to get a copy of the link for a file. Is there a way to query dropbox and get the shared links of all files that exist?

Thanks for your help. I am so new to this that my questions might not make sense, but hopefully you'll see what I'm up to and can answer accordingly.

Greg-DB

@mikemalter No problem:

1. No, shared folders are not the same as shared links. There's a help center article that covers these two different kinds of sharing here:

https://help.dropbox.com/files-folders/share-file-or-folder

2. Yes, you can call the API from essentially any platform where you can make arbitrary HTTPS calls. If you're using C#, we recommend using the official Dropbox API v2 .NET SDK, if you can. The SDK will do most of the work for you. For example, it has a CreateSharedLinkWithSettingsAsync method for /2/sharing/create_shared_link_with_settings.

3. Yes, you can retrieve existing shared links using /2/sharing/list_shared_links (which is ListSharedLinksAsync in the .NET SDK).

mikemalter

Hi Greg,

If I create a shared link to a folder, that does not mean that all of it's contents now have shared links. Please confirm my understanding that it's a one to one thing. Thanks.

Also, some nuances with regard to shared links. Let's say on Monday I programattically create shared links for all files and folders in our Dropbox. Then someone adds new files and folders. Can I run the same program that basically gets each item and assigns a shared link to it, or do I need to differentiate between those items who do not have a shared link and create a shared link. Will it mess anything up if I just run my shared link utility on our whole dropbox each time? I want to make sure I don't create issues on the back end for anyone.

Finally the first parameter for CreateSharedLinkWithSettingsAsync is the path of the item. So the path to an example file is "C:\Users\malter.JOYOUSLIVING\Dropbox\FoldernameLevel1\FolderNameLevel1\FileName.pdf". Is this what I pass, or do I pass the stuff just after Dropbox, or do I include Dropbox. I don't see any example code, so I'm having to wing this. Are there code examples?

Thanks.

Greg-DB

If you create a shared link to a folder, that link is specifically for the folder. However, that link does also enable access to the contents of that folder.

If you attempt to create a shared link for a file or folder that already has a shared link, the call will fail with an error. You can catch that error though. I illustrated that as well as the path question here in the issue you opened for the .NET SDK:

https://github.com/dropbox/dropbox-sdk-dotnet/issues/64

Hope this helps!

mikemalter

Greg,

Is is possible you could post a snippet of C# code that shows how to call an async method from another class? I want to have a class called DropboxManager where I can put all of the Dropbox code in and then call those methods. But I can't figure out how to pass parameters without another level of indirection. Here are some code snippets to help you understand. This is in the Form_Load method of my Windows Form application

this.dbx = DropboxManager.GetUserToken(this.DropboxDevelopmentAccessToken);

Task<FullAccount> task = Task.Run(GetCurrentAccount);
task.Wait();
this.full = task.Result;

this.lblDropboxUserName.Text = full.Name.DisplayName;
this.lblDropboxEmailAddress.Text = full.Email;

Task<List<string>> task1 = Task.Run(ListFolders);
task1.Wait();
int i = task1.Result.Count;

Here are the functions that are another level of indirection and in the same class as the Form_Load method.

async Task<List<string>> ListFolders()
{
	DropboxManager dm = new DropboxManager();
	List<string> FolderList = await dm.ListFolders(dbx);

	return FolderList;
}

async Task<FullAccount> GetCurrentAccount()
{
	try
	{
		DropboxManager dm = new DropboxManager();
		return await dm.GetCurrentAccount(dbx);
	}
	catch (Exception e)
	{
		throw e;
	}
}

Here are the methods that are called in my DropboxManager class:

public async Task<List<string>> ListFolders(DropboxClient dbx)
{
	try
	{
		List<string> FolderList = new List<string>();
		var list = await dbx.Files.ListFolderAsync(string.Empty);

		foreach (var item in list.Entries.Where(i => i.IsFolder))
		{
			FolderList.Add(item.Name);
		}

		return FolderList;
	}
	catch (Exception ex)
	{
		throw ex;
	}
}

public static DropboxClient GetUserToken(string oauth2AccessToken)
{
	try
	{
		DropboxClient dbx = new DropboxClient(oauth2AccessToken);
		return dbx;
	}
	catch (Exception e)
	{
		throw e;
	}
}

public async Task<FullAccount> GetCurrentAccount(DropboxClient dbx)
{
	try
	{
		return await dbx.Users.GetCurrentAccountAsync();
	}
	catch (Exception e)
	{
		throw e;
	}
}

So you can see that the only way I can pass parameters is by executing a Run() on an async function that calls another async function. I can't figure out how to pass parameters from that first level. Is that even possible?

Thanks.

Greg-DB

Hi Mike, unfortunately this question sounds more like a general C# question about class and method structure and usage, which I'm afraid I can't offer help with, as it's out of scope for Dropbox API support and outside my area of expertise. Apologies I can't be of more help in that regard!

mikemalter

Greg,

No issues. I eventually got it worked out.

I am having an error thrown everytime I call CreateSharedLinkWithSettingsAsync. The message says: {"Value should match pattern '\\A(?:(/(.|[\\r\\n])*|id:.*)|(rev:[0-9a-f]{9,})|(ns:[0-9]+(/.*)?))\\z'\r\nParameter name: path"} and the PathLower value is: "\\NW Region Info Table Documents\\0 Special Documents please read first file in this folder\\DropboxForSeva.docx". I parsed out my local drive and folders and trimmed everything to the right of \\Dropbox. What am I missing?

Thanks!

Greg-DB

The error message is indicating that that's not a valid path value. The Dropbox path format doesn't necessarily match local filesystem path formats. For example, in this case, the path should be like "/NW Region Info Table Documents/0 Special Documents please read first file in this folder/DropboxForSeva.docx".

In general, you should just get the PathLower value from the Metadata objects returned by other API calls, such as listFolder.

mikemalter

Greg,

I'm trying to synch a desktop application UI with Dropbox and I started by getting a third party control that is a tree folder control. How sure are you that Dropbox's storage is not mirrored on my machine?

Do you have a code sample for listFolder if all I have is a path from my computer? Do I have enough information on my end to get metadata from Dropbox for a particular item?
Do you have a code sample for getting file metadata?

Thank you.

Greg-DB

If you use the official Dropbox desktop client, it will sync the contents of your Dropbox account to your local filesystem. Note that your local filesystem doesn't use the same path format as the remote Dropbox API though. For example, Dropbox API paths uses '/' as a separator, and not '\'.

1. The Dropbox API isn't really meant for use based on file paths originating from your local filesystem like this. It provides the entire file listing for your from the API itself. E.g., using listFolder as shown here:

https://github.com/dropbox/dropbox-sdk-dotnet/blob/9803a40b3169acf66a2d14e29af8750ebe6e3e17/dropbox-sdk-dotnet/Examples/SimpleTest/Program.cs#L267

(If you need to list the root Dropbox folder, using the empty string "" as the path.)

You can technically convert a local filesystem path, though I don't have sample code for that. For instance though, you can find the local Dropbox folder using this:

https://help.dropbox.com/desktop-web/locate-dropbox-folder

Then, you can strip off the local folder root, and convert the path as necessary. (E.g., from '\" separators to "/".)

2. The listFolder method as above will return metadata, but you can also retrieve individual file metadata using GetMetadata as shown here:

https://github.com/dropbox/dropbox-sdk-dotnet/blob/9803a40b3169acf66a2d14e29af8750ebe6e3e17/dropbox-sdk-dotnet/Dropbox.Api.Tests/DropboxApiTests.cs#L91

Pash237

I have exactly the same question, but I'm writing native iOS application in ObjC.

I searched, but can't find a way to get the temporary link for a file. I found mysterious `DBFILESGetTemporaryLink` and `DBFILESGetTemporaryLinkArg`, but I don't know how to use them.

I just need an external URL for a file in Dropbox — don't want to download it to a temporary location or data in memory.

Greg-DB

@Pash237 In the Dropbox API v2 Objective-C SDK, you would use the DBFILESUserAuthRoutes -getTemporaryLink: method:

https://dropbox.github.io/dropbox-sdk-obj-c/api-docs/latest/Classes/DBFILESUserAuthRoutes.html#/c:objc(cs)DBFILESUserAuthRoutes(im)getTemporaryLink:

That's an RPC-style method, so it would be used the same way as the createFolder example here:

https://github.com/dropbox/dropbox-sdk-obj-c#rpc-style-request

(I.e., `[[client.filesRoutes getTemporaryLink...`)

Pash237

Thanks, it works!

[[client.filesRoutes getTemporaryLink:path]
setResponseBlock:^(DBFILESGetTemporaryLinkResult *result, DBFILESGetTemporaryLinkError *routeError, DBRequestError *networkError) {
if (result) {
         NSLog("Got URL for Dropbox file: ", result.link);
      }
   }];

rahlpanchal

Can you please share the function that you have tried as I have same requirement and if you shared it would be helpful for me.

Thanks!

Greg-DB

@rahlpanchal Pash237 shared an example of using the getTemporaryLink method. Is that not what you're looking for? If not, please feel free to open a new thread with the details of your question.

iCodes

Hello Greg i have the same problem with this error : "{"Value should match pattern '\\A(?:(/(.|[\\r\\n])*|id:.*)|(rev:[0-9a-f]{9,})|(ns:[0-9]+(/.*)?))\\z'\r\nParameter name: path"}"

heres my code:

try
{
var result = await dbx.Sharing.CreateSharedLinkWithSettingsAsync(@E:/Dropbox/iCodesStorageDropbox/H11018304_MMCH/CF1- TR18-0000005-121212-JOSESAPANZAAMIDO.enc, null);
var url = result.Url;
MessageBox.Show(url);
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
}

Greg-DB

@iCodes I see you also opened another thread for this so I'll follow up there:

https://www.dropboxforum.com/t5/API-Support-Feedback/HELP/m-p/283564#M17366

lenner90

can i get the temporary link of the whole folder not just the file.

my convern is I am geting multiple image from dropbox , it take time to get temporary link one by one.

or any better solution?

Greg-DB

@lenner90 No, unfortunately it's not possible to get a temporary link for a folder itself, or for multiple files in bulk, but I'll pass this along as a feature request.