File write permission in Azure Function App - azure

Question

I am using Azure Function App
I am using CSVHelper package to create file, But CSVHelper needs local file path first to Create/Write file.
using (var writer = new StreamWriter(filePath))
using (var csvData = new CsvWriter(writer, CultureInfo.InvariantCulture))
{
// Write input in csv
csvData.WriteRecords(input);
}
What path can I use to create file in Azure Function App?

Answer 1

Since it looks like you're using a StreamWriter, you could also write to a MemoryStream instead of creating an actual file. This feels like a better route to take with Azure Functions.
If you're really set on creating an actual file, you can do so by using System.IO.Path.GetTempPath(), which will always return a valid path for any given system. Create your temporary file there, then continue with the process.
Please take into account that your Function might run multiple times on the same environment, so be sure to use a unique filename.

Answer 2

For future reference:
private static void ExportContentToCsv(ILogger log, IEnumerable<T> content)
{
var path = Path.Combine(Path.GetTempPath(), "content.csv");
log.LogInformation($"Writing csv file at {path}");
if (File.Exists(path))
{
log.LogInformation("Deleting existent resources...");
File.Delete(path);
}
using (var writer = new StreamWriter(path))
{
using (var csv = new CsvWriter(writer, CultureInfo.InvariantCulture))
{
csv.WriteRecords(content);
}
}
}