Generate a Client method for Dropshot websocket channels

Generated methods return `ResponseValue<reqwest::Upgrade`, which may be
passed to a websocket protocol implementation such as
`tokio_tungstenite::WebSocketStream::from_raw_stream(rv.into_inner(), ...)`
for the purpose of implementing against the raw websocket connection, but
may later be extended as a generic to allow higher-level channel message
definitions.

Per the changelog, consumers will need to depend on reqwest 0.11.12 or
newer for HTTP Upgrade support, as well as base64 and rand if any
endpoints are websocket channels:
```
[dependencies]
reqwest = { version = "0.11.12" features = ["json", "stream"] }
base64 = "0.13"
rand = "0.8"
```

CHANGELOG.adoc

@@ -24,6 +24,7 @@ https://github.com/oxidecomputer/progenitor/compare/v0.1.1\...v0.2.0[Full list o
 * Derive `Debug` for `Client` and builders for the various operations (#145)
 * Builders for `struct` types (#171)
 * Add a prelude that include the `Client` and any extension traits (#176)
+* Add support for upgrading connections, which requires a version bump to reqwest. (#183)
 
 == 0.1.1 (released 2022-05-13)
 

README.md

@@ -54,6 +54,13 @@ Similarly if there is a `format` field set to `uuid`:
 +uuid = { version = "1.0.0", features = ["serde", "v4"] }
 ```
 
+And if there are any websocket channel endpoints:
+```diff
+[dependencies]
++base64 = "0.13"
++rand = "0.8"
+```
+
 The macro has some additional fancy options to control the generated code:
 
 ```rust
@@ -116,7 +123,7 @@ You'll need to add add the following to `Cargo.toml`:
 +serde_json = "1.0"
 ```
 
-(`chrono` and `uuid` as above)
+(`chrono`, `uuid`, `base64`, and `rand` as above)
 
 Note that `progenitor` is used by `build.rs`, but the generated code required
 `progenitor-client`.
@@ -290,4 +297,4 @@ let result = client
 ```
 
 Consumers do not need to specify parameters and struct properties that are not
-required or for which the API specifies defaults. Neat!
+required or for which the API specifies defaults. Neat!

example-build/Cargo.toml

@@ -7,7 +7,9 @@ edition = "2021"
 [dependencies]
 chrono = { version = "0.4", features = ["serde"] }
 progenitor-client = { path = "../progenitor-client" }
-reqwest = { version = "0.11", features = ["json", "stream"] }
+reqwest = { version = "0.11.12", features = ["json", "stream"] }
+base64 = "0.13"
+rand = "0.8"
 serde = { version = "1.0", features = ["derive"] }
 uuid = { version = "1.0", features = ["serde", "v4"] }
 

example-macro/Cargo.toml

@@ -7,7 +7,7 @@ edition = "2021"
 [dependencies]
 chrono = { version = "0.4", features = ["serde"] }
 progenitor = { path = "../progenitor" }
-reqwest = { version = "0.11", features = ["json", "stream"] }
+reqwest = { version = "0.11.12", features = ["json", "stream"] }
 schemars = { version = "0.8.10", features = ["uuid1"] }
 serde = { version = "1.0", features = ["derive"] }
 uuid = { version = "1.0", features = ["serde", "v4"] }

progenitor-client/Cargo.toml

@@ -10,7 +10,7 @@ description = "An OpenAPI client generator - client support"
 bytes = "1.2.1"
 futures-core = "0.3.24"
 percent-encoding = "2.2"
-reqwest = { version = "0.11", default-features = false, features = ["json", "stream"] }
+reqwest = { version = "0.11.12", default-features = false, features = ["json", "stream"] }
 serde = "1.0"
 serde_json = "1.0"
 serde_urlencoded = "0.7.1"

progenitor-client/src/progenitor_client.rs

@@ -76,6 +76,30 @@ impl<T: DeserializeOwned> ResponseValue<T> {
     }
 }
 
+impl ResponseValue<reqwest::Upgraded> {
+    #[doc(hidden)]
+    pub async fn upgrade<E: std::fmt::Debug>(
+        response: reqwest::Response,
+    ) -> Result<Self, Error<E>> {
+        let status = response.status();
+        let headers = response.headers().clone();
+        if status == reqwest::StatusCode::SWITCHING_PROTOCOLS {
+            let inner = response
+                .upgrade()
+                .await
+                .map_err(Error::InvalidResponsePayload)?;
+
+            Ok(Self {
+                inner,
+                status,
+                headers,
+            })
+        } else {
+            Err(Error::UnexpectedResponse(response))
+        }
+    }
+}
+
 impl ResponseValue<ByteStream> {
     #[doc(hidden)]
     pub fn stream(response: reqwest::Response) -> Self {

progenitor-impl/src/lib.rs

@@ -26,6 +26,8 @@ pub enum Error {
     UnexpectedFormat(String),
     #[error("invalid operation path {0}")]
     InvalidPath(String),
+    #[error("invalid dropshot extension use: {0}")]
+    InvalidExtension(String),
     #[error("internal error {0}")]
     InternalError(String),
 }
@@ -36,6 +38,7 @@ pub struct Generator {
     type_space: TypeSpace,
     settings: GenerationSettings,
     uses_futures: bool,
+    uses_websockets: bool,
 }
 
 #[derive(Default, Clone)]
@@ -116,6 +119,7 @@ impl Default for Generator {
             ),
             settings: Default::default(),
             uses_futures: Default::default(),
+            uses_websockets: Default::default(),
         }
     }
 }
@@ -133,6 +137,7 @@ impl Generator {
             type_space: TypeSpace::new(&type_settings),
             settings: settings.clone(),
             uses_futures: false,
+            uses_websockets: false,
         }
     }
 
@@ -426,7 +431,7 @@ impl Generator {
             "bytes = \"1.1\"",
             "futures-core = \"0.3\"",
             "percent-encoding = \"2.1\"",
-            "reqwest = { version = \"0.11\", features = [\"json\", \"stream\"] }",
+            "reqwest = { version = \"0.11.12\", features = [\"json\", \"stream\"] }",
             "serde = { version = \"1.0\", features = [\"derive\"] }",
             "serde_urlencoded = \"0.7\"",
         ];
@@ -444,6 +449,10 @@ impl Generator {
         if self.uses_futures {
             deps.push("futures = \"0.3\"")
         }
+        if self.uses_websockets {
+            deps.push("base64 = \"0.13\"");
+            deps.push("rand = \"0.8\"");
+        }
         if self.type_space.uses_serde_json() {
             deps.push("serde_json = \"1.0\"")
         }