http: improved recognition of url pointing to a single file - fixes #5929

docs/content/http.md

@@ -12,7 +12,26 @@ webservers such as Apache/Nginx/Caddy and will likely work with file
 listings from most web servers.  (If it doesn't then please file an
 issue, or send a pull request!)
 
-Paths are specified as `remote:` or `remote:path/to/dir`.
+Paths are specified as `remote:` or `remote:path`.
+
+The `remote:` represents the configured [url](#http-url), and any path following
+it will be resolved relative to this url, according to the URL standard. This
+means with remote url `https://beta.rclone.org/branch` and path `fix`, the
+resolved URL will be `https://beta.rclone.org/branch/fix`, while with path
+`/fix` the resolved URL will be `https://beta.rclone.org/fix` as the absolute
+path is resolved from the root of the domain.
+
+If the path following the `remote:` ends with `/` it will be assumed to point
+to a directory. If the path does not end with `/`, then a HEAD request is sent
+and the response used to decide if it it is treated as a file or a directory
+(run with `-vv` to see details). When [--http-no-head](#http-no-head) is
+specified, a path without ending `/` is always assumed to be a file. If rclone
+incorrectly assumes the path is a file, the solution is to specify the path with
+ending `/`. When you know the path is a directory, ending it with `/` is always
+better as it avoids the initial HEAD request.
+
+To just download a single file it is easier to use
+[copyurl](/commands/rclone_copyurl/).
 
 ## Configuration
 
@@ -81,25 +100,29 @@ Sync the remote `directory` to `/home/local/directory`, deleting any excess file
 
     rclone sync -i remote:directory /home/local/directory
 
-### Read only ###
+### Read only
 
 This remote is read only - you can't upload files to an HTTP server.
 
-### Modified time ###
+### Modified time
 
 Most HTTP servers store time accurate to 1 second.
 
-### Checksum ###
+### Checksum
 
 No checksums are stored.
 
-### Usage without a config file ###
+### Usage without a config file
 
 Since the http remote only has one config parameter it is easy to use
 without a config file:
 
     rclone lsd --http-url https://beta.rclone.org :http:
 
+or:
+
+    rclone lsd :http,url='https://beta.rclone.org':
+
 {{< rem autogenerated options start" - DO NOT EDIT - instead edit fs.RegInfo in backend/http/http.go then run make backenddocs" >}}
 ### Standard options