Serve plain events depending on Accept, update docs

2021-06-11 15:13:24 +02:00
parent b736905448
commit 321b31d6a6
5 changed files with 140 additions and 61 deletions
--- a/daqbuffer/src/test/events.rs
+++ b/daqbuffer/src/test/events.rs
@@ -275,7 +275,7 @@ async fn get_plain_events_json(
    let req = hyper::Request::builder()
        .method(http::Method::GET)
        .uri(url)
-        .header("Accept", "application/octet-stream")
+        .header("Accept", "application/json")
        .body(Body::empty())?;
    let client = hyper::Client::new();
    let res = client.request(req).await?;
--- a/disk/src/channelexec.rs
+++ b/disk/src/channelexec.rs
@@ -321,7 +321,12 @@ impl ChannelExecFunction for PlainEventsJson {
        );
        let f = collect_plain_events_json(s, self.timeout);
        let f = FutureExt::map(f, |item| match item {
-            Ok(item) => Ok(Bytes::from(serde_json::to_vec(&item)?)),
+            Ok(item) => {
+                // TODO add channel entry info here?
+                //let obj = item.as_object_mut().unwrap();
+                //obj.insert("channelName", JsonValue::String(en));
+                Ok(Bytes::from(serde_json::to_vec(&item)?))
+            }
            Err(e) => Err(e.into()),
        });
        let s = futures_util::stream::once(f);
--- a/disk/src/events.rs
+++ b/disk/src/events.rs
@@ -71,7 +71,7 @@ impl PlainEventsQuery {
    pub fn url(&self, host: &HostPort) -> String {
        let date_fmt = "%Y-%m-%dT%H:%M:%S.%3fZ";
        format!(
-            "http://{}:{}/api/4/plain_events?channelBackend={}&channelName={}&begDate={}&endDate={}&timeout={}",
+            "http://{}:{}/api/4/events?channelBackend={}&channelName={}&begDate={}&endDate={}&timeout={}",
            host.host,
            host.port,
            self.channel.backend,
@@ -150,7 +150,7 @@ impl PlainEventsJsonQuery {
    pub fn url(&self, host: &HostPort) -> String {
        let date_fmt = "%Y-%m-%dT%H:%M:%S.%3fZ";
        format!(
-            "http://{}:{}/api/4/alpha_plain_events_json?channelBackend={}&channelName={}&begDate={}&endDate={}&timeout={}",
+            "http://{}:{}/api/4/events?channelBackend={}&channelName={}&begDate={}&endDate={}&timeout={}",
            host.host,
            host.port,
            self.channel.backend,
--- a/httpret/src/lib.rs
+++ b/httpret/src/lib.rs
@@ -2,7 +2,7 @@ use crate::gather::gather_get_json;
 use bytes::Bytes;
 use disk::binned::prebinned::pre_binned_bytes_for_http;
 use disk::binned::query::{BinnedQuery, PreBinnedQuery};
-use disk::events::PlainEventsQuery;
+use disk::events::{PlainEventsJsonQuery, PlainEventsQuery};
 use disk::raw::conn::events_service;
 use err::Error;
 use future::Future;
@@ -170,18 +170,12 @@ async fn http_service_try(req: Request<Body>, node_config: &NodeConfigCached) ->
        } else {
            Ok(response(StatusCode::METHOD_NOT_ALLOWED).body(Body::empty())?)
        }
-    } else if path == "/api/4/plain_events" {
+    } else if path == "/api/4/events" {
        if req.method() == Method::GET {
            Ok(plain_events(req, &node_config).await?)
        } else {
            Ok(response(StatusCode::METHOD_NOT_ALLOWED).body(Body::empty())?)
        }
-    } else if path == "/api/4/alpha_plain_events_json" {
-        if req.method() == Method::GET {
-            Ok(plain_events_json(req, &node_config).await?)
-        } else {
-            Ok(response(StatusCode::METHOD_NOT_ALLOWED).body(Body::empty())?)
-        }
    } else if path.starts_with("/api/4/gather/") {
        if req.method() == Method::GET {
            Ok(gather_get_json(req, &node_config).await?)
@@ -260,8 +254,8 @@ where
 {
    Response::builder()
        .status(status)
-        .header("access-control-allow-origin", "*")
-        .header("access-control-allow-headers", "*")
+        .header("Access-Control-Allow-Origin", "*")
+        .header("Access-Control-Allow-Headers", "*")
 }

 struct BodyStreamWrap(netpod::BodyStream);
@@ -400,6 +394,21 @@ async fn prebinned(req: Request<Body>, node_config: &NodeConfigCached) -> Result
 }

 async fn plain_events(req: Request<Body>, node_config: &NodeConfigCached) -> Result<Response<Body>, Error> {
+    let accept_def = "";
+    let accept = req
+        .headers()
+        .get("Accept")
+        .map_or(accept_def, |k| k.to_str().unwrap_or(accept_def));
+    if accept == "application/json" {
+        Ok(plain_events_json(req, node_config).await?)
+    } else if accept == "application/octet-stream" {
+        Ok(plain_events_binary(req, node_config).await?)
+    } else {
+        Err(Error::with_msg(format!("unexpected Accept: {:?}", accept)))
+    }
+}
+
+async fn plain_events_binary(req: Request<Body>, node_config: &NodeConfigCached) -> Result<Response<Body>, Error> {
    let (head, _body) = req.into_parts();
    let query = PlainEventsQuery::from_request(&head)?;
    let op = disk::channelexec::PlainEvents::new(query.channel().clone(), query.range().clone(), node_config.clone());
@@ -411,7 +420,7 @@ async fn plain_events(req: Request<Body>, node_config: &NodeConfigCached) -> Res

 async fn plain_events_json(req: Request<Body>, node_config: &NodeConfigCached) -> Result<Response<Body>, Error> {
    let (head, _body) = req.into_parts();
-    let query = PlainEventsQuery::from_request(&head)?;
+    let query = PlainEventsJsonQuery::from_request(&head)?;
    let op = disk::channelexec::PlainEventsJson::new(
        query.channel().clone(),
        query.range().clone(),
--- a/httpret/static/documentation/api4.html
+++ b/httpret/static/documentation/api4.html
@@ -26,10 +26,118 @@ Currently available:
 <h2>API functions</h2>
 <p>Currently available functionality:</p>
 <ul>
-    <li><a href="#query-binned">Query binned data</a></li>
    <li><a href="#search-channel">Search channel</a></li>
+    <li><a href="#query-binned">Query binned data</a></li>
+    <li><a href="#query-events">Query event data</a></li>
 </ul>

+
+
+<a id="search-channel"></a>
+<h2>Search channel</h2>
+<p><strong>Method:</strong> GET</p>
+<p><strong>URL:</strong> https://data-api.psi.ch/api/4/search/channel</p>
+<p><strong>Query parameters:</strong></p>
+<ul>
+    <li>nameRegex (e.g. "LSCP.*6")</li>
+    <li>sourceRegex  (e.g. "178:9999")</li>
+    <li>descriptionRegex  (e.g. "celsius")</li>
+</ul>
+<p><strong>Request header:</strong> "Accept" must be "application/json"</p>
+
+<h4>CURL example:</h4>
+<pre>
+curl -H 'Accept: application/json' 'https://data-api.psi.ch/api/4/search/channel?sourceRegex=CV.E.+37&nameRegex=120.+y2$'
+</pre>
+
+<h4>Example response:</h4>
+<pre>
+{
+  "channels": [
+    {
+      "name": "S10MA01-DBPM120:Y2",
+      "backend": "sf-databuffer",
+      "source": "tcp://S20-CVME-DBPM2371:9000",
+      "type": "Float32",
+      "shape": [],
+      "unit": "",
+      "description": ""
+    },
+    {
+      "name": "S20SY02-DBPM120:Y2",
+      "backend": "sf-databuffer",
+      "source": "tcp://S20-CVME-DBPM2371:9000",
+      "type": "Float32",
+      "shape": [],
+      "unit": "",
+      "description": ""
+    }
+  ]
+}
+</pre>
+<p>The search constraints are AND'd.</p>
+
+
+
+
+<a id="query-events"></a>
+<h2>Query event data</h2>
+<p><strong>Method:</strong> GET</p>
+<p><strong>URL:</strong> https://data-api.psi.ch/api/4/events</p>
+<p><strong>Query parameters:</strong></p>
+<ul>
+    <li>channelBackend (e.g. "sf-databuffer")</li>
+    <li>channelName  (e.g. "SLAAR-LSCP4-LAS6891:CH7:1")</li>
+    <li>begDate  (e.g. "2021-05-26T07:10:00.000Z")</li>
+    <li>endDate  (e.g. "2021-05-26T07:16:00.000Z")</li>
+</ul>
+<p><strong>Request header:</strong> "Accept" must be "application/json"</p>
+
+<h4>CURL example:</h4>
+<pre>
+curl -H 'Accept: application/json' 'https://data-api.psi.ch/api/4/events?channelBackend=sf-databuffer&channelName=SLAAR-LSCP4-LAS6891:CH7:1&begDate=2021-06-11T07:00:00.000Z&endDate=2021-06-11T07:00:01.000Z'
+</pre>
+
+<h4>Timestamp format</h4>
+<p>Javascript can not represent the full 64-bit integer and the databuffer nanosecond timestamps would lose precision.
+Therefore, timestamps are represented in the response by <strong>ts0</strong> which gives an absolute anchor
+in time in units of seconds, and the array <strong>tsoff</strong> with the offset of each event in microseconds.</p>
+
+<h4>Timeout</h4>
+<p>If the requested range takes too long to retrieve, then the flags <strong>timedOut: true</strong> will be set.</p>
+
+<p>Example response:</p>
+<pre>
+{
+  "finalisedRange": true,
+  "ts0": 1623394800,
+  "tsoff": [
+    68461150,
+    169461160,
+    269461170,
+    369461180,
+    479461191,
+    579461201,
+    ...
+  ],
+  "values": [
+    [378, 325, 321, 381, ... waveform of 1st event ],
+    [334, 355, 360, 345, ... waveform of 2nd event ],
+    ...
+  ]
+}
+</pre>
+
+<h4>Complete result</h4>
+<p>If the result does not contain a <strong>continueAt</strong> key then the result is complete.</p>
+
+<h4>Finalised range</h4>
+<p>If the server can determine that no more data will be added to the requested time range
+    then it will add the flag <strong>finalisedRange: true</strong> to the response.</p>
+
+
+
+
 <a id="query-binned"></a>
 <h2>Query binned data</h2>
 <p><strong>Method:</strong> GET</p>
@@ -57,7 +165,8 @@ starts with the first not-yet-retrieved bin.</p>
 <p>This information is provided by the <strong>continueAt</strong> and <strong>missingBins</strong> fields.</p>
 <p>This enables the user agent to start the presentation to the user while updating the user interface
 as new bins are received.</p>
-<p>Example:</p>
+
+<p>Example response:</p>
 <pre>
 {
  "continueAt": "2021-05-25T16:00:00.000Z",
@@ -104,50 +213,6 @@ as new bins are received.</p>
 then it will add the flag <strong>finalisedRange: true</strong> to the response.</p>


-<a id="search-channel"></a>
-<h2>Search channel</h2>
-<p><strong>Method:</strong> GET</p>
-<p><strong>URL:</strong> https://data-api.psi.ch/api/4/search/channel</p>
-<p><strong>Query parameters:</strong></p>
-<ul>
-    <li>nameRegex (e.g. "LSCP.*6")</li>
-    <li>sourceRegex  (e.g. "178:9999")</li>
-    <li>descriptionRegex  (e.g. "celsius")</li>
-</ul>
-<p><strong>Request header:</strong> "Accept" must be "application/json"</p>
-
-<h4>CURL example:</h4>
-<pre>
-curl -H 'Accept: application/json' 'https://data-api.psi.ch/api/4/search/channel?sourceRegex=CV.E.+37&nameRegex=120.+y2$'
-</pre>
-
-<h4>Example result</h4>
-<pre>
-{
-  "channels": [
-    {
-      "name": "S10MA01-DBPM120:Y2",
-      "backend": "sf-databuffer",
-      "source": "tcp://S20-CVME-DBPM2371:9000",
-      "type": "Float32",
-      "shape": [],
-      "unit": "",
-      "description": ""
-    },
-    {
-      "name": "S20SY02-DBPM120:Y2",
-      "backend": "sf-databuffer",
-      "source": "tcp://S20-CVME-DBPM2371:9000",
-      "type": "Float32",
-      "shape": [],
-      "unit": "",
-      "description": ""
-    }
-  ]
-}
-</pre>
-<p>The search constraints are AND'd.</p>
-

 <h2>Feedback and comments very much appreciated!</h2>
 <p>dominik.werder@psi.ch</p>