Installation

The library

Requires Go 1.27 or later.

go get github.com/caffeine-projects/vlatte

Import the packages you use: mockhttp for HTTP, mockgrpc for gRPC, and match for matchers.

Package	What it's for
mockhttp	HTTP mock servers
mockgrpc	gRPC mock servers
match	Request matchers, such as match.Equal, match.JSONPath and match.All
match/matchbuild	The matcher lists of mock files, and the registry of custom matchers
match/matchscenario	Scenario state for mock servers
webhook	Calling a URL after a mock is served
fault	Pipes that make an HTTP mock answer wrong
journal	The request journal
admin	The admin API
recipe/<protocol>/<recipe>	Recipes that prepare a server, such as recipe/http/proxyall
vlatte	The types every mock server shares, and the Go template engine

The CLI

Homebrew

On macOS and Linux:

brew install caffeine-projects/tap/vlatte

Homebrew installs the latest stable release. For a release candidate, use its archive or Docker image, or go install with its tag, such as @v0.2.0-rc.1.

An archive

GitHub Releases has an archive for Linux, macOS and Windows, on amd64 and arm64. Each holds the vlatte binary, which needs nothing else:

VERSION=v0.1.0-rc.1
curl -fsSL "https://github.com/caffeine-projects/vlatte/releases/download/$VERSION/vlatte_${VERSION#v}_linux_amd64.tar.gz" | tar -xz vlatte

Go

Requires Go 1.27 or later.

go install github.com/caffeine-projects/vlatte/cmd/vlatte@latest

Docker

The image is ghcr.io/caffeine-projects/vlatte, for linux/amd64 and linux/arm64: see Docker.

docker run --rm ghcr.io/caffeine-projects/vlatte:v0.1.0-rc.1 version

Verifying a release

The release workflow of this repository builds every archive and image, and signs them with cosign without a key: the signature names the workflow and the tag it ran for. Each archive also has an SBOM, <archive>.sbom.json, and a provenance attestation.

An archive: check the signature of checksums.txt, then the archive against it.

VERSION=v0.1.0-rc.1
ARCHIVE="vlatte_${VERSION#v}_linux_amd64.tar.gz"
gh release download "$VERSION" -R caffeine-projects/vlatte -p checksums.txt -p checksums.txt.sigstore.json -p "$ARCHIVE"

cosign verify-blob checksums.txt \
  --bundle checksums.txt.sigstore.json \
  --certificate-identity "https://github.com/caffeine-projects/vlatte/.github/workflows/release.yml@refs/tags/$VERSION" \
  --certificate-oidc-issuer https://token.actions.githubusercontent.com
sha256sum --ignore-missing -c checksums.txt # shasum -a 256 on macOS

Or, with the GitHub CLI alone, check its provenance:

gh attestation verify "$ARCHIVE" -R caffeine-projects/vlatte

The image:

cosign verify "ghcr.io/caffeine-projects/vlatte:$VERSION" \
  --certificate-identity "https://github.com/caffeine-projects/vlatte/.github/workflows/release.yml@refs/tags/$VERSION" \
  --certificate-oidc-issuer https://token.actions.githubusercontent.com
gh attestation verify "oci://ghcr.io/caffeine-projects/vlatte:$VERSION" -R caffeine-projects/vlatte

Versions

Versions follow semantic versioning. Until v1.0.0, a minor version may change the API. A version with a suffix, such as v0.1.0-rc.1, is a release candidate. The changes of each version are on GitHub Releases.

Editor support for mock files

Mock files have JSON Schemas at stable addresses. Point your editor at them to get completion and validation: see Mock file schemas.