Capability to set contentType not available in python binding

[jokester]

I don't know much rust or python please don't put full trust in me.

When trying to use opendal in a python project I failed to find a way to set contentType when uploading a file to Object Storage service like GCS.

After investigated the core code it seems to me that,

1. in core the capability is provided via BlockingOperator.{write_with,writer_with} Operator.{write_with,writer_with}
2. such capability is not available in python binding

[jokester]

If this is confirmed I'm happy to try making a PR. I still want to use opendal and this actually blocks my work.

[Xuanwo]

Would you like to share the design for implementing write_with in Python before makeing a PR?

[jokester]

Would you like to share the design for implementing write_with in Python before makeing a PR?

Sure. Like you I considered to add a write_with because there is already write in py binding.

I guess the changes will be this shape:

diff --git a/bindings/python/src/lib.rs b/bindings/python/src/lib.rs
index 2d90c602..1887993e 100644
--- a/bindings/python/src/lib.rs
+++ b/bindings/python/src/lib.rs
@@ -124,6 +124,11 @@ impl Operator {
         self.0.write(path, bs).map_err(format_pyerr)
     }
 
+    pub fn write_with(&self, path: &str, bs: Vec<u8>) -> PyResult<FunctionWrite> {
+        todo!()
+    }
+
     /// Get current path's metadata **without cache** directly.
     pub fn stat(&self, path: &str) -> PyResult<Metadata> {
         self.0.stat(path).map_err(format_pyerr).map(Metadata)
@@ -200,6 +205,13 @@ impl Reader {
     }
 }
 
+#[pyclass(module = "opendal")]
+struct FunctionWrite(od::operator_functions::FunctionWrite);
+
+impl FunctionWrite {
+    // ... expose inner capabilities to python
+}

And some similar changes to AsyncOperator.

Finally in python we can write like:

operator.write_with(path, blob).content_type("image/png").call()

[Xuanwo]

This design seems not native to python users. Maybe we can accept kwargs instead in python, so users can write code like:

op.write(path, blob, content_type="image/png")

Also cc python binding maintainer @messense for comments.

[jokester]

No problem for me. I don't use much python either so I'll try to be very open to your comments 👍🏽