go-codex-client

A lightweight Go client utility for interacting with Codex client.

Project layout

• communities/codex_client.go — core HTTP client (upload/download, context-aware streaming)
• cmd/upload/ — CLI to upload a file to Codex
• cmd/download/ — CLI to download a file by CID
• .github/copilot-instructions.md — guidance for AI coding agents

We will be running codex client, and then use a small testing utility to check if the low level abstraction - CodexClient - correctly uploads and downloads the content.

Running CodexClient

I often remove some logging noise, by slightly changing the build params in build.nims (nim-codex):

task codex, "build codex binary":
  buildBinary "codex",
    # params = "-d:chronicles_runtime_filtering -d:chronicles_log_level=TRACE"
    params =
      "-d:chronicles_runtime_filtering -d:chronicles_log_level=TRACE -d:chronicles_enabled_topics:restapi:TRACE,node:TRACE"

You see a slightly more selective params in the codex task.

To run the client I use the following command:

./build/codex --data-dir=./data-1 --listen-addrs=/ip4/127.0.0.1/tcp/8081 --api-port=8001 --nat=none --disc-port=8091 --log-level=TRACE

Building codex-upload and codex-download utilities

Use the following command to build the codex-upload and codex-download utilities:

go build -o bin/codex-upload ./cmd/upload
go build -o bin/codex-download ./cmd/download

Uploading content to Codex

Now, using the codex-upload utility, we can upload the content to Codex as follows:

~/code/local/go-codex-client
❯ ./bin/codex-upload -file test-data.bin -host localhost -port 8001
Uploading test-data.bin (43 bytes) to Codex at localhost:8001...
✅ Upload successful!
CID: zDvZRwzm8K7bcyPeBXcZzWD7AWc4VqNuseduDr3VsuYA1yXej49V

Downloading content from Codex

Now, having the content uploaded to Codex - let's get it back using the codex-download utility:

~/code/local/go-codex-client
❯ ./bin/codex-download -cid zDvZRwzm8K7bcyPeBXcZzWD7AWc4VqNuseduDr3VsuYA1yXej49V -file output.bin -host localhost -port 8001
Downloading CID zDvZRwzm8K7bcyPeBXcZzWD7AWc4VqNuseduDr3VsuYA1yXej49V from Codex at localhost:8001...
✅ Download successful!
Saved to: output.bin

You can easily compare that the downloaded content matches the original using:

~/code/local/go-codex-client
❯ openssl sha256 test-data.bin
SHA2-256(test-data.bin)= c74ce73165c288348b168baffc477b6db38af3c629b42a7725c35d99d400d992

~/code/local/go-codex-client
❯ openssl sha256 output.bin
SHA2-256(output.bin)= c74ce73165c288348b168baffc477b6db38af3c629b42a7725c35d99d400d992

Running tests

There are a couple of basic tests, including one integration test.

To run the unit tests:

❯ go test -v ./communities
=== RUN   TestUpload_Success
--- PASS: TestUpload_Success (0.00s)
=== RUN   TestDownload_Success
--- PASS: TestDownload_Success (0.00s)
=== RUN   TestDownloadWithContext_Cancel
--- PASS: TestDownloadWithContext_Cancel (0.04s)
PASS
ok  	go-codex-client/communities	0.044s

To run the integration test, use integration tag and narrow the scope using -run Integration:

go test -v -tags=integration ./communities -run Integration -timeout 15s

To make sure that the test is actually run and not cached, use count option:

go test -v -tags=integration ./communities -run Integration -timeout 15s -count 1