jolt-lang/http-client

clj-http-lite running on Jolt.

clj-http-lite is a small, dependency-light Clojure HTTP client built on the JVM's java.net.HttpURLConnection. Jolt has no JVM, so this library supplies the host APIs clj-http-lite needs as Jolt host shims — the same approach jolt-lang/router uses for reitit. None of it lives in jolt core: requiring this library installs the shims at load.

(require '[jolt.http-client :as http])

(http/get "https://example.com")
(http/get "https://api.example.com/things" {:query-params {"q" "jolt"} :as :json})
(http/post "https://example.com/x" {:body "{\"a\":1}" :content-type :json})
;; also: head, put, delete, and the lower-level request

The functions mirror clj-http.lite.client exactly — see its docs for the full request/response map.

What it provides

clj-http-lite uses	Jolt shim
java.net.URL, HttpURLConnection	hand-rolled HTTP/1.1 client over BSD sockets via jolt.ffi (jolt.http.net / jolt.http.platform)
java.io.ByteArrayInput/OutputStream	byte-stream tagged-tables wired into io/copy / slurp
java.util.zip (gzip/deflate)	the system libz via jolt.ffi (jolt.http.zlib)
javax.net.ssl (https, insecure?)	the system OpenSSL via jolt.ffi, memory-BIO TLS over the socket (jolt.http.tls)
java.net.http.HttpClient (JDK 11+ client)	the modern client/request builders (HttpClient/HttpRequest/HttpResponse + BodyPublishers/BodyHandlers/HttpHeaders); used by cognitect aws-api's java backend. send and sendAsync go over the same socket/TLS layer as everything else; sendAsync hands back an already-settled future, enough for thenApply/exceptionally but not a real CompletableFuture.

The native libraries (libc sockets, libz, OpenSSL) are declared in deps.edn under :jolt/native; jolt loads them before the namespaces are required.

Timeouts

:conn-timeout and :socket-timeout are milliseconds, and both are off unless you pass them.

(http/get "https://example.com" {:conn-timeout 2000 :socket-timeout 10000})

:conn-timeout bounds each connect attempt, the way java.net.Socket's does — a name resolving to a dead address and a live one still connects, and the dead one costs at most the timeout instead of the kernel's SYN retry window (~75s on macOS, ~130s on Linux). :socket-timeout bounds each individual read.

Neither bounds a peer that keeps trickling bytes: every read beats the read timeout, so the response never ends. (jolt.http.platform/set-max-response-ms! ms) caps the total wall-clock time of a response body across all reads. It applies process-wide, and is nil (uncapped) by default.

Requirements

• jolt 0.6.8 or newer. jolt.http.net binds fcntl through jolt.ffi's :varargs marker, which landed in 0.6.8; older builds fail at namespace load with unknown foreign type :varargs.
• System libz (always present) and OpenSSL (libssl/libcrypto) for https.

Tests

jolt -M:test runs clj-http-lite's own client, links and integration suites under Jolt. The suites are vendored under test/clj_http/lite; their server-process fixture is replaced with in-process plaintext + TLS servers (jolt.http.test-server, over jolt.ffi sockets + OpenSSL) in place of the suite's Jetty subprocess — no external checkout needed.

jolt -M:test

All 60 tests pass (116 assertions), including the self-signed-cert TLS test and the gzip/deflate decompression tests.

Three suites run separately, and CI runs only :test:

jolt -M:timeouttest   # timeout/deadline regressions; stalls connections on
                      # purpose and stands up its own servers, which the main
                      # suite's serial accept loop doesn't tolerate. One case
                      # loads jolt.nrepl in a subprocess and fetches
                      # https://example.com, so it needs network egress.
jolt -M:bhctest       # babashka.http-client over the java.net.http shim
jolt -M:zlibtest      # zlib round-trip, no sockets