Traffic Ops Client

This module is Blockcast's import-independent fork of the Apache Traffic Control Go client libraries. It is consumed by Magma and is released separately from Traffic Control.

Ownership

The GStack Release Engineer owns releases of this repository. The release owner is responsible for reviewing upstream sync scope, merging a green sync, tagging the release, and opening the corresponding Magma dependency bump.

Upstream changes are not published here automatically. A change to Traffic Control's lib/go-tc does not reach Magma until this repository is reconciled, tagged, and Magma is updated.

Upstream Re-sync

The fork is intentionally independent, but it is not intentionally frozen. Re-syncs are selective reconciliations, not directory replacements.

1. Start from the latest main and record the Traffic Control source commit in the pull request and sync commit. Update UPSTREAM.md with that exact commit and the sync date.
2. Inventory the overlap between upstream lib/go-tc/ and this repository's go-tc/. Every upstream file whose relative path already exists in go-tc/ is in scope for review. New upstream-only files are added only when a supported Blockcast consumer needs them.
3. Review each upstream diff and preserve intentional fork changes, including the github.com/Blockcast/trafficops-client module path, Blockcast API extensions, and Blockcast dependency substitutions. Rewrite imports from Traffic Control packages to the corresponding package in this module; do not restore github.com/apache/trafficcontrol imports.
4. Include related changes from the other extracted libraries (go-util/, go-rfc/, go-log/, go-llog/, toclientlib/, v4-client/, and v5-client/) when the selected go-tc changes depend on them.
5. Run go build ./... and go test ./.... Merge only after the repository CI workflow passes and the reconciliation has been reviewed.

The pull request must list files intentionally omitted from the sync and why. That list distinguishes a deliberate fork decision from accidental drift.

As verified on 2026-08-07, this fork's go-tc/ is a strict subset of upstream lib/go-tc/: 165 files overlap, 112 differ, 53 are byte-identical, 38 exist only upstream, and 0 exist only in the fork. The fork has no Blockcast-original go-tc files; its divergence is within files, primarily from import rewrites. Maintain the 0-fork-only invariant. Every sync pull request must report the file set comparison and explicitly explain any change to that invariant.

Deletion Pre-check

Before deleting a symbol from Traffic Control's lib/go-tc/, the engineer who owns the deletion must run both cross-repository checks:

1. Search this repository's go-tc/ for the symbol and its serialized values.
2. Search Blockcast Magma's cdn/ tree for the same identifiers and values.

Record both results in the Traffic Control deletion pull request. A local search in Traffic Control cannot clear either consumer. The GStack Release Engineer reviews a positive fork match to determine whether a selective sync, release, and Magma dependency bump are required before the deletion can land.

Check absence as well as presence. For example, MulticastServerType and AMT_RELAY occur in neither this fork nor Magma's cdn/, so that deletion has no Magma exposure through this module. Do not assume that result for other symbols, and do not assume a fork match implies a Magma use without the second search.

Release and Magma Bump

After a re-sync is merged and CI is green, the GStack Release Engineer:

1. Chooses the next semantic version and creates an annotated tag on the green main commit, for example git tag -a v0.1.6 -m "Release v0.1.6".
2. Pushes the tag with git push origin v0.1.6 and verifies that the tag points to the tested commit.
3. Opens a Magma pull request updating every trafficops-client version in cdn/cloud/go/go.mod, including both direct requirements and replacement directives, to the same new tag.
4. Runs the Magma CDN Go build and tests before merging the dependency bump.

Magma must not be bumped before the tag exists and this repository's CI is green. The Traffic Control change is not delivered to Magma until that bump is merged.