doc: update with a few words about the console

console/data/docs/03-usage.md

@@ -87,8 +87,69 @@ instances are still running an older version).
 
 ## Console service
 
-`akvorado console` starts the console service. Currently, only this
-documentation is accessible through this service.
+`akvorado console` starts the console service. It provides a web
+console. The home page is a simple dashboard with a few metrics, some
+graphs and a recent example of flow. The console also contains this
+documentation. The most interesting page is the “visualize” tab which
+allows a user to explore data using graphs.
+
+### Graph options
+
+The collapsible panel on the left has several options to change the
+aspect of the graph.
+
+- Four graph types are provided: “stacked”, “lines” and “grid” to
+  display time series and “sankey” to show flow distributions between
+  various dimensions.
+
+- The time range can be set from a list of preset or directly using
+  natural language. The parsing is done by
+  [SugarJS](https://sugarjs.com/dates/#/Parsing) which provides
+  examples of what can be done. Another alternative is to look at the
+  presets. Dates can also be entered using their ISO format:
+  `2022-05-22 12:33` for example.
+
+- A set of dimensions can be selected. For time series, dimensions are
+  converted to series. They are stacked when using “stacked”,
+  displayed as simple lines with “lines” and displayed in a grid with
+  “grid”. The grid representation can be useful if you need to compare
+  the volume of each dimension. For sankey graphs, dimensions are
+  converted to nodes. In this case, at least two dimensions need to be
+  selected.
+
+- Akvorado will only retrieve a limited number of series and the
+  "limit" parameter tells how many. The remaining values are
+  categorized as "Other".
+
+- The filter box contains an SQL-like expression to limit the data to
+  be graphed.
+
+The URL contains the encoded parameters and can be used to share with
+others. However, currently, no stability of the options are
+guaranteed, so an URL may stop working after a few upgrades.
+
+### Filter language
+
+The filter language looks like SQL with a few variations. Fields
+listed as dimensions can usually be used. Accepted operators are `=`,
+`!=`, `<`, `<=`, `>`, `>=`, `IN`, `LIKE`, `ILIKE`, when they make
+sense. Here are a few examples:
+
+ - `InIfBoundary = external` only selects flows whose incoming
+   interface was classified as external. The value should not be
+   quoted.
+ - `InIfConnectivity = "ix"` selects flows whose incoming interface is
+   connected to an IX.
+ - `SrcAS = AS12322`, `SrcAS = 12322`, `SrcAS IN (12322, 29447)`
+   limits the source AS number of selected flows.
+ - `SrcAddr = 203.0.113.4` only selects flows with the specified
+   address. Note that filtering on IP addresses is usually slower.
+ - `ExporterName LIKE th2-%` selects flows coming from routers
+   starting with `th2-`.
+
+The final SQL query sent to ClickHouse is logged inside the console
+after a successful request. It should be noted than using ports or
+addresses prevent the use of aggregated data and are therefore slower.
 
 ## Other commands
 

console/data/docs/06-internals.md

@@ -142,6 +142,51 @@ capacity.
 Testing is done by another implementation of an [SNMP
 agent](https://github.com/salyercat/GoSNMPServer).
 
+## Web console
+
+The web console is built as a REST API with a single page application
+on top of it.
+
+### REST API
+
+The REST API is mostly built using the [Gin
+framework](https://gin-gonic.com/) which removes some boilerplate
+compared to using pure Go. Also, it uses the [validator
+package](https://github.com/go-playground/validator) which implements
+value validations based on tags. The validation options are quite
+rich.
+
+### Single page application
+
+The SPA is built using mostly the following components:
+
+- [Yarn](https://yarnpkg.com/) as a package manager,
+- [Vite](https://vitejs.dev/) as a builder,
+- [Vue](https://vuejs.org/) as the reactive JavaScript framework,
+- [TailwindCSS](https://tailwindcss.com/) for styling pages directly inside HTML,
+- [Headless UI](https://headlessui.dev/) for some unstyled UI components,
+- [ECharts](https://echarts.apache.org/) to plot charts.
+
+There is no full-blown component library despite the existence of many candidates:
+
+- [Vuetify](https://vuetifyjs.com/) is only compatible with Vue 2.
+- [BootstrapVue](https://bootstrap-vue.org/) is only compatible with Vue 2.
+- [PrimeVue](https://www.primefaces.org/primevue/) is quite heavyweight and many stuff are not opensource.
+- [VueTailwind](https://www.vue-tailwind.com/) would be the perfect match but it is not compatible with Vue 2.
+- [Naive UI](https://www.naiveui.com/) may be a future option but the
+  styling is not using TailwindCSS which is annoying for responsive
+  stuff, but we can just stay away from the proposed layout.
+
+So, currently, components are mostly taken from
+[Flowbite](https://flowbite.com/), copy/pasted or from Headless UI and
+styled like Flowbite.
+
+Use of TailwindCSS is also a strong choice. Their
+[documentation](https://tailwindcss.com/docs/utility-first) explains
+this choice. It makes sense but this is sometimes a burden. Many
+components are scattered around the web and when there is no need for
+JS, it is just a matter of copy/pasting and customizing.
+
 ## Other components
 
 The core component is the main one. It takes the other as dependencies

console/frontend/src/views/VisualizePage.vue

@@ -133,7 +133,12 @@ const { data, isFetching, aborted, abort, canAbort, error } = useFetch("", {
   async afterFetch(ctx) {
     // Update data. Not done in a computed value as we want to keep the
     // previous data in case of errors.
-    const { data } = ctx;
+    const { data, response } = ctx;
+    console.groupCollapsed("SQL query");
+    console.info(
+      response.headers.get("x-sql-query").replace(/ {2}( )*/g, "\n$1")
+    );
+    console.groupEnd();
     fetchedData.value = {
       ...data,
       dimensions: payload.value.dimensions,

console/graph.go

@@ -114,7 +114,7 @@ func (c *Component) graphHandlerFunc(gc *gin.Context) {
 	}
 	sqlQuery = c.queryFlowsTable(sqlQuery,
 		query.Start, query.End, resolution)
-	gc.Header("X-SQL-Query", sqlQuery)
+	gc.Header("X-SQL-Query", strings.ReplaceAll(sqlQuery, "\n", "  "))
 
 	results := []struct {
 		Time       time.Time `ch:"time"`

console/sankey.go

@@ -110,7 +110,7 @@ func (c *Component) sankeyHandlerFunc(gc *gin.Context) {
 	// Prepare and execute query
 	sqlQuery = c.queryFlowsTable(sqlQuery,
 		query.Start, query.End, resolution)
-	gc.Header("X-SQL-Query", sqlQuery)
+	gc.Header("X-SQL-Query", strings.ReplaceAll(sqlQuery, "\n", "  "))
 	results := []struct {
 		Xps        float64  `ch:"xps"`
 		Dimensions []string `ch:"dimensions"`