Fallible setters, and fields.delete method (#69)

* Make the `fields.delete` method fallible
* Make setters fallible
* Regenerate proxy.md

Author: elliottt

proxy.md

@@ -785,6 +785,10 @@ exist.</p>
 <li><a name="method_fields.delete.self"><code>self</code></a>: borrow&lt;<a href="#fields"><a href="#fields"><code>fields</code></a></a>&gt;</li>
 <li><a name="method_fields.delete.name"><code>name</code></a>: <a href="#field_key"><a href="#field_key"><code>field-key</code></a></a></li>
 </ul>
+<h5>Return values</h5>
+<ul>
+<li><a name="method_fields.delete.0"></a> result&lt;_, <a href="#header_error"><a href="#header_error"><code>header-error</code></a></a>&gt;</li>
+</ul>
 <h4><a name="method_fields.append"><code>[method]fields.append: func</code></a></h4>
 <p>Append a value for a key. Does not change or delete any existing
 values for that key.</p>
@@ -888,17 +892,9 @@ return success at most once, and subsequent calls will return error.</p>
 <li><a name="method_incoming_request.consume.0"></a> result&lt;own&lt;<a href="#incoming_body"><a href="#incoming_body"><code>incoming-body</code></a></a>&gt;&gt;</li>
 </ul>
 <h4><a name="constructor_outgoing_request"><code>[constructor]outgoing-request: func</code></a></h4>
-<p>Construct a new <a href="#outgoing_request"><code>outgoing-request</code></a>.</p>
-<ul>
-<li><a href="#method"><code>method</code></a> represents the HTTP Method for the Request.</li>
-<li><code>path-with-query</code> is the combination of the HTTP Path and Query for
-the Request. When <code>none</code>, this represents an empty Path and empty
-Query.</li>
-<li><a href="#scheme"><code>scheme</code></a> is the HTTP Related Scheme for the Request. When <code>none</code>,
-the implementation may choose an appropriate default scheme.</li>
-<li><code>authority</code> is the HTTP Authority for the Request. A value of <code>none</code>
-may be used with Related Schemes which do not require an Authority.
-The HTTP and HTTPS schemes always require an authority.</li>
+<p>Construct a new <a href="#outgoing_request"><code>outgoing-request</code></a> with a default <a href="#method"><code>method</code></a> of <code>GET</code>, and
+<code>none</code> values for <code>path-with-query</code>, <a href="#scheme"><code>scheme</code></a>, and <code>authority</code>.</p>
+<ul>
 <li><a href="#headers"><code>headers</code></a> is the HTTP Headers for the Request.</li>
 </ul>
 <p>It is possible to construct, or manipulate with the accessor functions
@@ -908,10 +904,6 @@ It is the obligation of the <code>outgoing-handler.handle</code> implementation
 to reject invalid constructions of <a href="#outgoing_request"><code>outgoing-request</code></a>.</p>
 <h5>Params</h5>
 <ul>
-<li><a name="constructor_outgoing_request.method"><a href="#method"><code>method</code></a></a>: <a href="#method"><a href="#method"><code>method</code></a></a></li>
-<li><a name="constructor_outgoing_request.path_with_query"><code>path-with-query</code></a>: option&lt;<code>string</code>&gt;</li>
-<li><a name="constructor_outgoing_request.scheme"><a href="#scheme"><code>scheme</code></a></a>: option&lt;<a href="#scheme"><a href="#scheme"><code>scheme</code></a></a>&gt;</li>
-<li><a name="constructor_outgoing_request.authority"><code>authority</code></a>: option&lt;<code>string</code>&gt;</li>
 <li><a name="constructor_outgoing_request.headers"><a href="#headers"><code>headers</code></a></a>: own&lt;<a href="#headers"><a href="#headers"><code>headers</code></a></a>&gt;</li>
 </ul>
 <h5>Return values</h5>
@@ -943,12 +935,17 @@ calls will return error.</p>
 <li><a name="method_outgoing_request.method.0"></a> <a href="#method"><a href="#method"><code>method</code></a></a></li>
 </ul>
 <h4><a name="method_outgoing_request.set_method"><code>[method]outgoing-request.set-method: func</code></a></h4>
-<p>Set the Method for the Request.</p>
+<p>Set the Method for the Request. Fails if the string present in a
+<code>method.other</code> argument is not a syntactically valid method.</p>
 <h5>Params</h5>
 <ul>
 <li><a name="method_outgoing_request.set_method.self"><code>self</code></a>: borrow&lt;<a href="#outgoing_request"><a href="#outgoing_request"><code>outgoing-request</code></a></a>&gt;</li>
 <li><a name="method_outgoing_request.set_method.method"><a href="#method"><code>method</code></a></a>: <a href="#method"><a href="#method"><code>method</code></a></a></li>
 </ul>
+<h5>Return values</h5>
+<ul>
+<li><a name="method_outgoing_request.set_method.0"></a> result</li>
+</ul>
 <h4><a name="method_outgoing_request.path_with_query"><code>[method]outgoing-request.path-with-query: func</code></a></h4>
 <p>Get the combination of the HTTP Path and Query for the Request.
 When <code>none</code>, this represents an empty Path and empty Query.</p>
@@ -962,12 +959,17 @@ When <code>none</code>, this represents an empty Path and empty Query.</p>
 </ul>
 <h4><a name="method_outgoing_request.set_path_with_query"><code>[method]outgoing-request.set-path-with-query: func</code></a></h4>
 <p>Set the combination of the HTTP Path and Query for the Request.
-When <code>none</code>, this represents an empty Path and empty Query.</p>
+When <code>none</code>, this represents an empty Path and empty Query. Fails is the
+string given is not a syntactically valid path and query uri component.</p>
 <h5>Params</h5>
 <ul>
 <li><a name="method_outgoing_request.set_path_with_query.self"><code>self</code></a>: borrow&lt;<a href="#outgoing_request"><a href="#outgoing_request"><code>outgoing-request</code></a></a>&gt;</li>
 <li><a name="method_outgoing_request.set_path_with_query.path_with_query"><code>path-with-query</code></a>: option&lt;<code>string</code>&gt;</li>
 </ul>
+<h5>Return values</h5>
+<ul>
+<li><a name="method_outgoing_request.set_path_with_query.0"></a> result</li>
+</ul>
 <h4><a name="method_outgoing_request.scheme"><code>[method]outgoing-request.scheme: func</code></a></h4>
 <p>Get the HTTP Related Scheme for the Request. When <code>none</code>, the
 implementation may choose an appropriate default scheme.</p>
@@ -981,12 +983,17 @@ implementation may choose an appropriate default scheme.</p>
 </ul>
 <h4><a name="method_outgoing_request.set_scheme"><code>[method]outgoing-request.set-scheme: func</code></a></h4>
 <p>Set the HTTP Related Scheme for the Request. When <code>none</code>, the
-implementation may choose an appropriate default scheme.</p>
+implementation may choose an appropriate default scheme. Fails if the
+string given is not a syntactically valid uri scheme.</p>
 <h5>Params</h5>
 <ul>
 <li><a name="method_outgoing_request.set_scheme.self"><code>self</code></a>: borrow&lt;<a href="#outgoing_request"><a href="#outgoing_request"><code>outgoing-request</code></a></a>&gt;</li>
 <li><a name="method_outgoing_request.set_scheme.scheme"><a href="#scheme"><code>scheme</code></a></a>: option&lt;<a href="#scheme"><a href="#scheme"><code>scheme</code></a></a>&gt;</li>
 </ul>
+<h5>Return values</h5>
+<ul>
+<li><a name="method_outgoing_request.set_scheme.0"></a> result</li>
+</ul>
 <h4><a name="method_outgoing_request.authority"><code>[method]outgoing-request.authority: func</code></a></h4>
 <p>Get the HTTP Authority for the Request. A value of <code>none</code> may be used
 with Related Schemes which do not require an Authority. The HTTP and
@@ -1002,12 +1009,17 @@ HTTPS schemes always require an authority.</p>
 <h4><a name="method_outgoing_request.set_authority"><code>[method]outgoing-request.set-authority: func</code></a></h4>
 <p>Set the HTTP Authority for the Request. A value of <code>none</code> may be used
 with Related Schemes which do not require an Authority. The HTTP and
-HTTPS schemes always require an authority.</p>
+HTTPS schemes always require an authority. Fails if the string given is
+not a syntactically valid uri authority.</p>
 <h5>Params</h5>
 <ul>
 <li><a name="method_outgoing_request.set_authority.self"><code>self</code></a>: borrow&lt;<a href="#outgoing_request"><a href="#outgoing_request"><code>outgoing-request</code></a></a>&gt;</li>
 <li><a name="method_outgoing_request.set_authority.authority"><code>authority</code></a>: option&lt;<code>string</code>&gt;</li>
 </ul>
+<h5>Return values</h5>
+<ul>
+<li><a name="method_outgoing_request.set_authority.0"></a> result</li>
+</ul>
 <h4><a name="method_outgoing_request.headers"><code>[method]outgoing-request.headers: func</code></a></h4>
 <p>Get the headers associated with the Request.</p>
 <p>This headers resource is a child: it must be dropped before the parent
@@ -1201,14 +1213,14 @@ trailers were present in the body.</p>
 <li><a name="method_future_trailers.get.0"></a> option&lt;result&lt;option&lt;own&lt;<a href="#trailers"><a href="#trailers"><code>trailers</code></a></a>&gt;&gt;, <a href="#error"><a href="#error"><code>error</code></a></a>&gt;&gt;</li>
 </ul>
 <h4><a name="constructor_outgoing_response"><code>[constructor]outgoing-response: func</code></a></h4>
-<p>Construct an <a href="#outgoing_response"><code>outgoing-response</code></a>.</p>
+<p>Construct an <a href="#outgoing_response"><code>outgoing-response</code></a>, with a default <a href="#status_code"><code>status-code</code></a> of <code>200</code>.
+If a different <a href="#status_code"><code>status-code</code></a> is needed, it must be set via the
+<code>set-status-code</code> method.</p>
 <ul>
-<li><a href="#status_code"><code>status-code</code></a> is the HTTP Status Code for the Response.</li>
 <li><a href="#headers"><code>headers</code></a> is the HTTP Headers for the Response.</li>
 </ul>
 <h5>Params</h5>
 <ul>
-<li><a name="constructor_outgoing_response.status_code"><a href="#status_code"><code>status-code</code></a></a>: <a href="#status_code"><a href="#status_code"><code>status-code</code></a></a></li>
 <li><a name="constructor_outgoing_response.headers"><a href="#headers"><code>headers</code></a></a>: own&lt;<a href="#headers"><a href="#headers"><code>headers</code></a></a>&gt;</li>
 </ul>
 <h5>Return values</h5>
@@ -1226,12 +1238,17 @@ trailers were present in the body.</p>
 <li><a name="method_outgoing_response.status_code.0"></a> <a href="#status_code"><a href="#status_code"><code>status-code</code></a></a></li>
 </ul>
 <h4><a name="method_outgoing_response.set_status_code"><code>[method]outgoing-response.set-status-code: func</code></a></h4>
-<p>Set the HTTP Status Code for the Response.</p>
+<p>Set the HTTP Status Code for the Response. Fails if the status-code
+given is not a valid http status code.</p>
 <h5>Params</h5>
 <ul>
 <li><a name="method_outgoing_response.set_status_code.self"><code>self</code></a>: borrow&lt;<a href="#outgoing_response"><a href="#outgoing_response"><code>outgoing-response</code></a></a>&gt;</li>
 <li><a name="method_outgoing_response.set_status_code.status_code"><a href="#status_code"><code>status-code</code></a></a>: <a href="#status_code"><a href="#status_code"><code>status-code</code></a></a></li>
 </ul>
+<h5>Return values</h5>
+<ul>
+<li><a name="method_outgoing_response.set_status_code.0"></a> result</li>
+</ul>
 <h4><a name="method_outgoing_response.headers"><code>[method]outgoing-response.headers: func</code></a></h4>
 <p>Get the headers associated with the Request.</p>
 <p>This headers resource is a child: it must be dropped before the parent

wit/types.wit

@@ -92,13 +92,12 @@ interface types {
 
     /// Delete all values for a key. Does nothing if no values for the key
     /// exist.
-    delete: func(name: field-key);
+    delete: func(name: field-key) -> result<_, header-error>;
 
     /// Append a value for a key. Does not change or delete any existing
     /// values for that key.
     append: func(name: field-key, value: field-value) -> result<_, header-error>;
 
-
     /// Retrieve the full set of keys and values in the Fields. Like the
     /// constructor, the list represents each key-value pair. 
     ///
@@ -148,17 +147,9 @@ interface types {
   /// Represents an outgoing HTTP Request.
   resource outgoing-request {
 
-    /// Construct a new `outgoing-request`.
+    /// Construct a new `outgoing-request` with a default `method` of `GET`, and
+    /// `none` values for `path-with-query`, `scheme`, and `authority`.
     ///
-    /// * `method` represents the HTTP Method for the Request.
-    /// * `path-with-query` is the combination of the HTTP Path and Query for
-    ///    the Request. When `none`, this represents an empty Path and empty
-    ///    Query.
-    /// * `scheme` is the HTTP Related Scheme for the Request. When `none`,
-    ///    the implementation may choose an appropriate default scheme.
-    /// * `authority` is the HTTP Authority for the Request. A value of `none`
-    ///    may be used with Related Schemes which do not require an Authority.
-    ///    The HTTP and HTTPS schemes always require an authority.
     /// * `headers` is the HTTP Headers for the Request.
     ///
     /// It is possible to construct, or manipulate with the accessor functions
@@ -167,10 +158,6 @@ interface types {
     /// It is the obligation of the `outgoing-handler.handle` implementation
     /// to reject invalid constructions of `outgoing-request`.
     constructor(
-      method: method,
-      path-with-query: option<string>,
-      scheme: option<scheme>,
-      authority: option<string>,
       headers: headers
     );
 
@@ -184,31 +171,35 @@ interface types {
 
     /// Get the Method for the Request.
     method: func() -> method;
-    /// Set the Method for the Request.
-    set-method: func(method: method);
+    /// Set the Method for the Request. Fails if the string present in a
+    /// `method.other` argument is not a syntactically valid method.
+    set-method: func(method: method) -> result;
 
     /// Get the combination of the HTTP Path and Query for the Request.
     /// When `none`, this represents an empty Path and empty Query.
     path-with-query: func() -> option<string>;
     /// Set the combination of the HTTP Path and Query for the Request.
-    /// When `none`, this represents an empty Path and empty Query.
-    set-path-with-query: func(path-with-query: option<string>);
+    /// When `none`, this represents an empty Path and empty Query. Fails is the
+    /// string given is not a syntactically valid path and query uri component.
+    set-path-with-query: func(path-with-query: option<string>) -> result;
 
     /// Get the HTTP Related Scheme for the Request. When `none`, the
     /// implementation may choose an appropriate default scheme.
     scheme: func() -> option<scheme>;
     /// Set the HTTP Related Scheme for the Request. When `none`, the
-    /// implementation may choose an appropriate default scheme.
-    set-scheme: func(scheme: option<scheme>);
+    /// implementation may choose an appropriate default scheme. Fails if the
+    /// string given is not a syntactically valid uri scheme.
+    set-scheme: func(scheme: option<scheme>) -> result;
 
     /// Get the HTTP Authority for the Request. A value of `none` may be used
     /// with Related Schemes which do not require an Authority. The HTTP and
     /// HTTPS schemes always require an authority.
     authority: func() -> option<string>;
     /// Set the HTTP Authority for the Request. A value of `none` may be used
     /// with Related Schemes which do not require an Authority. The HTTP and
-    /// HTTPS schemes always require an authority.
-    set-authority: func(authority: option<string>);
+    /// HTTPS schemes always require an authority. Fails if the string given is
+    /// not a syntactically valid uri authority.
+    set-authority: func(authority: option<string>) -> result;
 
     /// Get the headers associated with the Request.
     ///
@@ -223,7 +214,7 @@ interface types {
   /// transport layer of the HTTP protocol.
   ///
   /// These timeouts are separate from any the user may use to bound a
-  /// blocking call to `wasi:io/poll.poll-list`.
+  /// blocking call to `wasi:io/poll.poll`.
   resource request-options {
     /// Construct a default `request-options` value.
     constructor();
@@ -351,16 +342,19 @@ interface types {
   /// Represents an outgoing HTTP Response.
   resource outgoing-response {
 
-    /// Construct an `outgoing-response`.
+    /// Construct an `outgoing-response`, with a default `status-code` of `200`.
+    /// If a different `status-code` is needed, it must be set via the
+    /// `set-status-code` method.
     ///
-    /// * `status-code` is the HTTP Status Code for the Response.
     /// * `headers` is the HTTP Headers for the Response.
-    constructor(status-code: status-code, headers: headers);
+    constructor(headers: headers);
 
     /// Get the HTTP Status Code for the Response.
     status-code: func() -> status-code;
-    /// Set the HTTP Status Code for the Response.
-    set-status-code: func(status-code: status-code);
+
+    /// Set the HTTP Status Code for the Response. Fails if the status-code
+    /// given is not a valid http status code.
+    set-status-code: func(status-code: status-code) -> result;
 
     /// Get the headers associated with the Request.
     ///