Support tracing the ClickHouse Java HTTP client

[jaydeluca]

Contributes to #11562

Instruments v1 of the clickhouse-client (https://github.com/ClickHouse/clickhouse-java/tree/main/clickhouse-client)

A few notes:

• I used version 0.5.0 as the earliest version of the clickhouse client in the instrumentation (most recent version is 0.6.1), if we think we need to go back further I can do that, but it felt like the client changes frequently, and with the release of the new client it didn't feel necessary.
• In 0.6.1 they have introduced an alpha of a v2 client. Once that stabilizes I can followup and instrument that as well

The tests cover all the same scenarios, but I also created a repo to experiment with the tracing and visualize with jaeger and all seems to work as expected:
https://github.com/jaydeluca/clickhouse-tracing

Example Async query (execute)

Example error:

[steverao]

Suggest to use static import here.

[steverao]

According to previous convention, the module should be named to clickhouse-client-0.5. Please pay attention to modify other places together.

[steverao]

If there is a module, according to convention, please remove extra clickhouse directory. use clickhouse-client-0.5 directly.

[devurandom]

I tried the OpenTelemetry JavaAgent 2.6.0 with our application (Java 11, Clojure 1.11.3, ClickHouse HTTP Client 0.6.2, using the Java HTTP Client). I still only see the spans created by io.opentelemetry.java-http-client. I looked at the traces using OpenTelemetry Collector ingesting into Grafana Tempo, and using https://github.com/dotnet/aspire/tree/main/src/Aspire.Dashboard locally, but both only show the io.opentelemetry.java-http-client spans.

Do we need to do something to enable the instrumentation?

We create nodes as (ClickHouseNodes/of "https://..." {...}). Our client is created as:

(defn- make-client
  ^ClickHouseClient [endpoint]
  (let [{:keys [scheme]} (uri/parse endpoint)
        protocol (ClickHouseProtocol/fromUriScheme scheme)]
    (ClickHouseClient/newInstance (into-array ClickHouseProtocol [protocol]))))

We use com.clickhouse.client.ClickHouseRequest, created using client.read(servers) like in https://clickhouse.com/docs/en/integrations/java#query:

(defn- make-read-request
  ^ClickHouseRequest [^ClickHouseClient client ^ClickHouseNodes nodes ^String query & {:as params}]
  (let [^Map raw-params (-> params
                            (update-keys name)
                            (update-vals #(ClickHouseValues/convertToSqlExpression %)))]
    (doto (.read client nodes)
      (.format ClickHouseFormat/RowBinaryWithNamesAndTypes)
      (.query query)
      (.params raw-params))))

And also com.clickhouse.client.ClickHouseRequest.Mutation, created using client.read(servers).write() like in https://clickhouse.com/docs/en/integrations/java#insert:

(defn- make-write-request
  ^ClickHouseRequest$Mutation [^ClickHouseClient client ^ClickHouseNodes nodes ^String query & {::keys [^InputStream input-stream]
                                                                                                :as    params}]
  (let [^Map raw-params (-> params
                            (dissoc ::input-stream)
                            (update-keys name)
                            (update-vals #(ClickHouseValues/convertToSqlExpression %)))]
    (doto (.write (.read client nodes))
      (.format ClickHouseFormat/RowBinaryWithNamesAndTypes)
      (.query query)
      (.params raw-params)
      (cond-> input-stream (.data input-stream)))))

[jaydeluca]

@devurandom in the code examples you cite from the documentation, each method chain ends in an executeAndWait() or execute(), which is what is instrumented in the java agent.

I'm not too familiar with clojure, so maybe i'm missing something, but I don't see how your query is actually invoked in your example code.

I would think you would need to add in the .executeAndWait with something like:

(defn- make-read-request
  ^ClickHouseRequest [^ClickHouseClient client ^ClickHouseNodes nodes ^String query & {:as params}]
  (let [^Map raw-params (-> params
                            (update-keys name)
                            (update-vals #(ClickHouseValues/convertToSqlExpression %)))]
    (doto (.read client nodes)
      (.format ClickHouseFormat/RowBinaryWithNamesAndTypes)
      (.query query)
      (.params raw-params)
      (.executeAndWait))))

If this is not the case, could you help me with putting together a small basic sample app in clojure that I could experiment with? I tried writing something using some of your provided example code but I'm having issues getting everything working.

[devurandom]

If this is not the case, could you help me with putting together a small basic sample app in clojure that I could experiment with? I tried writing something using some of your provided example code but I'm having issues getting everything working.

I created #11851 and https://github.com/devurandom/opentelemetry-java-instrumentation-clickhouse-clojure-mwe to reproduce this in a small example application.

Thanks for looking into this!