From 87fa9f8e463c93e9d366d81caa2fae75c5d0bb9d Mon Sep 17 00:00:00 2001
From: rkettelerij <richard@mindloops.nl>
Date: Mon, 14 Nov 2022 10:51:49 +0100
Subject: [PATCH] azureblob: Add support for custom upload headers

---
 backend/azureblob/azureblob.go | 20 ++++++++++++++++++++
 docs/content/azureblob.md      | 12 ++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/backend/azureblob/azureblob.go b/backend/azureblob/azureblob.go
index 8c49a50dd..6c46419f5 100644
--- a/backend/azureblob/azureblob.go
+++ b/backend/azureblob/azureblob.go
@@ -1685,6 +1685,26 @@ func (o *Object) Update(ctx context.Context, in io.Reader, src fs.ObjectInfo, op
 		}
 	}
 
+	// Apply upload options (also allows one to overwrite content-type)
+	for _, option := range options {
+		key, value := option.Header()
+		lowerKey := strings.ToLower(key)
+		switch lowerKey {
+		case "":
+			// ignore
+		case "cache-control":
+			httpHeaders.CacheControl = value
+		case "content-disposition":
+			httpHeaders.ContentDisposition = value
+		case "content-encoding":
+			httpHeaders.ContentEncoding = value
+		case "content-language":
+			httpHeaders.ContentLanguage = value
+		case "content-type":
+			httpHeaders.ContentType = value
+		}
+	}
+
 	uploadParts := maxUploadParts
 	if uploadParts < 1 {
 		uploadParts = 1
diff --git a/docs/content/azureblob.md b/docs/content/azureblob.md
index 5a1e2663f..6f0200b3b 100644
--- a/docs/content/azureblob.md
+++ b/docs/content/azureblob.md
@@ -514,6 +514,18 @@ Properties:
 
 {{< rem autogenerated options stop >}}
 
+### Custom upload headers
+
+You can set custom upload headers with the `--header-upload` flag. 
+
+- Cache-Control
+- Content-Disposition
+- Content-Encoding
+- Content-Language
+- Content-Type
+
+Eg `--header-upload "Content-Type: text/potato"`
+
 ## Limitations
 
 MD5 sums are only uploaded with chunked files if the source has an MD5