Checkpoint Lab — User Interface, Search, Browse, Components, Assets, Tags, Uploads, and Repository Navigation

1. Scenario and success criteria

A release-support team needs a small evidence-backed catalog for a synthetic library. You will create the hosted repository if it does not already exist, publish versions 1.0.0, 1.0.1 and 1.1.0, verify component/assets through multiple views, model a logical build label without requiring Pro, diagnose one intentionally wrong query, then remove only the lab repository.

The checkpoint passes when another operator can reconstruct what changed from the evidence directory without relying on screenshots or memory.

2. Setup, assumptions and preflight

LAB="$HOME/nexus-ch03-lab"
NX_URL="http://127.0.0.1:8081"
mkdir -p "$LAB/evidence" "$LAB/payload"
umask 077
read -rsp "Disposable Nexus admin password: " NX_PASS; printf "\n"
printf 'machine 127.0.0.1 login admin password %s\n' "$NX_PASS" > "$LAB/nexus.netrc"
unset NX_PASS
NETRC="$LAB/nexus.netrc"

# Never commit or print $NETRC. Delete it when the lab ends.

curl -fsS "$NX_URL/service/rest/v1/status" | tee "$LAB/evidence/cp-01-status.txt"
curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/repositories" \
  | tee "$LAB/evidence/cp-02-repositories-before.json"

# Stop if this name belongs to anything except your disposable lab.
curl --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/repositories/academy-ch03-checkpoint" \
  | tee "$LAB/evidence/cp-03-existing-repo-check.json" || true

3. Record predictions before mutation

Write observed results next to each prediction. A prediction is useful even when wrong because it forces you to identify which state model needs correction.

4. Ensure the disposable repository exists

The checkpoint uses a fresh repository name, academy-ch03-checkpoint, so it does not depend on Lesson 2 state. First prove the name is absent; then create exactly one Maven hosted repository through the supported Repositories API.

cat > "$LAB/checkpoint-repo.json" <<'JSON'
{
  "name": "academy-ch03-checkpoint",
  "online": true,
  "storage": {
    "blobStoreName": "default",
    "strictContentTypeValidation": true,
    "writePolicy": "ALLOW_ONCE"
  },
  "maven": {
    "versionPolicy": "RELEASE",
    "layoutPolicy": "STRICT",
    "contentDisposition": "INLINE"
  }
}
JSON

curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  -H 'Content-Type: application/json' \
  -X POST "$NX_URL/service/rest/v1/repositories/maven/hosted" \
  --data-binary @"$LAB/checkpoint-repo.json"

curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/repositories/academy-ch03-checkpoint" \
  | tee "$LAB/evidence/cp-03b-repository-created.json"

5. Generate three synthetic versions

python3 - <<'PY'
from pathlib import Path
from zipfile import ZipFile, ZIP_DEFLATED
root = Path.home() / "nexus-ch03-lab" / "payload-checkpoint"
root.mkdir(parents=True, exist_ok=True)
for v in ("1.0.0", "1.0.1", "1.1.0"):
    note = root / f"README-{v}.txt"
    note.write_text(f"synthetic ui-demo version {v}\n", encoding="utf-8")
    jar = root / f"ui-demo-{v}.jar"
    with ZipFile(jar, "w", ZIP_DEFLATED) as z:
        z.write(note, "README.txt")
    pom = root / f"ui-demo-{v}.pom"
    pom.write_text(
        '<project xmlns="http://maven.apache.org/POM/4.0.0">\n'
        '  <modelVersion>4.0.0</modelVersion>\n'
        '  <groupId>com.example.academy</groupId>\n'
        '  <artifactId>ui-demo</artifactId>\n'
        f'  <version>{v}</version>\n'
        '</project>\n',
        encoding="utf-8",
    )
PY
sha256sum "$LAB"/payload-checkpoint/*.{jar,pom} 2>/dev/null \
  | tee "$LAB/evidence/cp-04-local-checksums.txt"

This fresh checkpoint repository starts empty and uses ALLOW_ONCE. Upload each release coordinate exactly once; a repeated upload is a failure to diagnose, not a reason to weaken the write policy.

6. Upload missing versions and capture status

for V in 1.0.0 1.0.1 1.1.0; do
  curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
    -X POST "$NX_URL/service/rest/v1/components?repository=academy-ch03-checkpoint" \
    -F maven2.groupId=com.example.academy \
    -F maven2.artifactId=ui-demo \
    -F maven2.version="$V" \
    -F maven2.asset1=@"$LAB/payload-checkpoint/ui-demo-$V.jar" \
    -F maven2.asset1.extension=jar \
    -F maven2.asset2=@"$LAB/payload-checkpoint/ui-demo-$V.pom" \
    -F maven2.asset2.extension=pom
done

All three versions are uploaded in this fresh checkpoint. If any POST fails, preserve the response and diagnose repository name/type, coordinate existence, payload fields and authorization before retrying.

7. Verify browse, search, assets and direct retrieval

curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/search?repository=academy-ch03-checkpoint&group=com.example.academy&name=ui-demo" \
  | tee "$LAB/evidence/cp-05-search-all.json"

curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/assets?repository=academy-ch03-checkpoint" \
  | tee "$LAB/evidence/cp-06-assets.json"

for V in 1.0.0 1.0.1 1.1.0; do
  curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
    "$NX_URL/repository/academy-ch03-checkpoint/com/example/academy/ui-demo/$V/ui-demo-$V.jar" \
    -o "$LAB/evidence/download-$V.jar"
  sha256sum "$LAB/evidence/download-$V.jar"
done | tee "$LAB/evidence/cp-07-download-checksums.txt"

In Browse, navigate the repository and inspect one version's component plus both assets. In Search, filter by group/name and then by an exact version. In API evidence, record component IDs, asset IDs, paths and checksums. Direct retrieval proves the path can serve bytes under the current authorization.

8. Annotate/document the logical build without requiring Pro

cat > "$LAB/evidence/cp-08-logical-tag-simulation.json" <<'JSON'
{
  "simulation": true,
  "feature": "Nexus Repository component tagging",
  "licenseBoundary": "Pro-only at review time",
  "logicalTag": "chapter03-release-train-001",
  "components": [
    "com.example.academy:ui-demo:1.0.0",
    "com.example.academy:ui-demo:1.0.1",
    "com.example.academy:ui-demo:1.1.0"
  ],
  "note": "A real Nexus tag associates components, not individual assets."
}
JSON

Optional Pro trial: use the documented Tags API to create and associate a tag, then prove the association in UI/API. Mark that evidence optional Pro; the CE checkpoint passes using the simulation manifest.

9. Controlled diagnostic challenge

Query a deliberately misspelled artifact ID, save the empty result, then prove the correct coordinate and direct asset still work:

curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/search?repository=academy-ch03-checkpoint&group=com.example.academy&name=ui-dmeo" \
  | tee "$LAB/evidence/cp-09-wrong-search.json"

curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/search?repository=academy-ch03-checkpoint&group=com.example.academy&name=ui-demo&version=1.1.0" \
  | tee "$LAB/evidence/cp-10-correct-search.json"

Explain why index rebuild, database edits and cache deletion would be unrelated. The misspelled query is the fault; the correct repair is the query string.

10. Evidence packet

11. Pre-delete inventory, supported deletion and verification

Repository deletion is intentionally last. Review the target name three times: in repository configuration, in search results, and in the command itself. Save a final component/asset inventory before deletion.

curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/search?repository=academy-ch03-checkpoint" \
  > "$LAB/evidence/cp-11-predelete-search.json"

printf 'TARGET=%s\n' 'academy-ch03-checkpoint' | tee "$LAB/evidence/cp-12-delete-target.txt"

# Run only after manually verifying the disposable target above.
curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  -X DELETE "$NX_URL/service/rest/v1/repositories/academy-ch03-checkpoint"

curl --fail-with-body --silent --show-error --netrc-file "$NETRC" \
  "$NX_URL/service/rest/v1/repositories" \
  | tee "$LAB/evidence/cp-13-repositories-after.json"

# Expected non-success because the repository no longer exists.
curl --silent --show-error -o /dev/null -w 'http=%{http_code}\n' \
  "$NX_URL/repository/academy-ch03-checkpoint/com/example/academy/ui-demo/1.1.0/ui-demo-1.1.0.jar" \
  | tee "$LAB/evidence/cp-14-after-delete-request.txt"

rm -f "$NETRC"

Do not manually remove corresponding blob files. Nexus repository deletion is the supported control for this disposable object. Blob-store reclamation/cleanup has its own semantics and later chapters; direct filesystem deletion would bypass Nexus state tracking.

12. What Chapter 03 adds to the production operating model

Chapter 01 established artifact identity and repository-manager purpose. Chapter 02 established supported runtime, process and persistent-state boundaries. Chapter 03 adds an inspection and evidence discipline: operators can prove repository type, component/asset identity, searchable metadata, retrievable bytes and authorization-visible views before changing state. It also establishes that UI convenience, REST automation, package-native publication and Pro-only metadata features are separate controls.

Knowledge check

13. Summary

You completed an end-to-end repository evidence cycle: preflight, predict, create/reuse, publish, search, browse, inspect assets, retrieve exact bytes, simulate a licensed metadata concept honestly, diagnose a harmless failure, inventory evidence and clean up through a supported Nexus API.

Official references and version notes

• Download Nexus Repository — the official download page used to pin the same 3.94.1-06 self-hosted lab baseline as Chapter 02 while current indexes are rechecked before execution.
• Browsing Repositories — browse-tree behavior, 10,000-component-per-level UI limit, HTML view, and browse/read privilege distinctions.
• Searching for Components — current UI search behavior, first-300-result display, SQL-search semantics, tokenization, exact phrases, and wildcard rules.
• Search API — component/asset search endpoints and continuation-token pagination.
• Viewing Component Information — component identifiers and the relationship to associated assets.
• Viewing Asset Information — asset path, content type, size, blob timestamps/reference, checksums, uploader metadata, and format-specific attributes.
• Uploading Components — hosted-only UI upload boundary and required upload/browse/read privileges.
• Components API — list/get/delete components and format-specific multipart component upload.
• Assets API — paginated asset listing, asset details, paths, download URLs and checksums.
• Repositories API — repository inventory and format/type-specific repository configuration endpoints.
• Privileges — current browse, read, add, edit, delete and search privilege semantics.
• Tagging and Self-Hosted Feature Matrix — component tagging is currently a Pro feature; mandatory Chapter 03 work does not require it.

Version-sensitive statements were rechecked against Sonatype primary documentation on 2026-08-26. The mandatory path remains self-hosted, Community/free-compatible and disposable. The chapter keeps the Chapter 02 lab baseline at Nexus Repository 3.94.1-06 because Sonatype's current download and versions-status pages still present 3.94.1 as the current downloadable/GA line; learners are told to re-check those pages before running the lab.