Add generator correctness and end-to-end tests

Author: tommasobo

htsim/README.md

@@ -154,6 +154,12 @@ The SlimFly generator script is adapted from the SPCL topology-generation toolin
 
 Note: topology generation scripts require Python packages `networkx` and `sympy`.
 
+Quick generator validation (small checks + end-to-end SOURCE runs for Dragonfly and SlimFly):
+
+```bash
+bash tests/run_generator_tests.sh
+```
+
 ### Traffic Matrix Format
 
 All topologies use the same traffic matrix format:

tests/run_generator_tests.sh

@@ -0,0 +1,132 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+DF_GEN="$ROOT_DIR/htsim/sim/datacenter/topologies/dragonfly/generate_dragonfly_assets.py"
+SF_GEN="$ROOT_DIR/htsim/sim/datacenter/topologies/slimfly/generate_slimfly_assets.py"
+DF_BIN="$ROOT_DIR/htsim/sim/datacenter/htsim_uec_df"
+SF_BIN="$ROOT_DIR/htsim/sim/datacenter/htsim_uec_sf"
+
+REF_DF="$ROOT_DIR/htsim/sim/datacenter/topologies/dragonfly/p2a4h2"
+
+PASS=0
+FAIL=0
+
+fail() {
+    echo "FAIL: $1"
+    FAIL=$((FAIL + 1))
+}
+
+pass() {
+    echo "PASS: $1"
+    PASS=$((PASS + 1))
+}
+
+require_file() {
+    local path="$1"
+    local msg="$2"
+    if [[ -f "$path" ]]; then
+        pass "$msg"
+    else
+        fail "$msg (missing: $path)"
+    fi
+}
+
+require_dir() {
+    local path="$1"
+    local msg="$2"
+    if [[ -d "$path" ]]; then
+        pass "$msg"
+    else
+        fail "$msg (missing: $path)"
+    fi
+}
+
+echo "=== Generator tests (small + end-to-end) ==="
+
+if ! python3 -c "import networkx, sympy" >/dev/null 2>&1; then
+    echo "ERROR: missing Python dependencies. Install with: pip install networkx sympy"
+    exit 1
+fi
+
+if [[ ! -x "$DF_BIN" || ! -x "$SF_BIN" ]]; then
+    echo "ERROR: missing simulator binaries. Build HTSIM first (cmake --build ...)."
+    exit 1
+fi
+
+TMP_DIR="$(mktemp -d)"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+echo "Using temp directory: $TMP_DIR"
+
+DF_OUT="$TMP_DIR/dragonfly_p2a1h1"
+DF_LOG="$TMP_DIR/dragonfly_compare.log"
+python3 "$DF_GEN" -p 2 -a 1 -H 1 --out "$DF_OUT" >/dev/null
+
+require_file "$DF_OUT/dragonfly.topo" "Dragonfly generator writes dragonfly.topo"
+require_file "$DF_OUT/dragonfly.adjlist" "Dragonfly generator writes dragonfly.adjlist"
+require_dir "$DF_OUT/host_table" "Dragonfly generator writes host_table directory"
+require_file "$DF_OUT/host_table/0.lt" "Dragonfly host table includes switch 0"
+require_file "$DF_OUT/host_table/1.lt" "Dragonfly host table includes switch 1"
+
+if [[ -d "$REF_DF/host_table" ]]; then
+    python3 "$DF_GEN" -p 2 -a 4 -H 2 --out "$TMP_DIR/dragonfly_p2a4h2" --compare-ref "$REF_DF" >"$DF_LOG"
+fi
+
+if [[ ! -d "$REF_DF/host_table" ]]; then
+    pass "Dragonfly compare-ref skipped (no host_table in $REF_DF)"
+elif grep -q "generated pairs subset of reference: yes" "$DF_LOG" && grep -q "average generated-pair coverage in reference: 1.000" "$DF_LOG"; then
+    pass "Dragonfly generator matches reference host-table coverage"
+else
+    fail "Dragonfly compare-ref coverage check"
+fi
+
+cat >"$TMP_DIR/df_1flow.tm" <<'EOF'
+Nodes 4
+Connections 1
+0->3 start 0 size 4096
+EOF
+
+"$DF_BIN" -basepath "$DF_OUT" -routing SOURCE -tm "$TMP_DIR/df_1flow.tm" >"$TMP_DIR/df_run.out" 2>&1 || true
+if grep -q "Done" "$TMP_DIR/df_run.out" && [[ "$(grep -c 'finished at' "$TMP_DIR/df_run.out")" -eq 1 ]]; then
+    pass "Dragonfly SOURCE end-to-end run succeeds with generated assets"
+else
+    fail "Dragonfly SOURCE end-to-end run"
+fi
+
+SF_OUT="$TMP_DIR/slimfly_p2q3"
+python3 "$SF_GEN" -p 2 -q 3 --out "$SF_OUT" -n 1 >/dev/null
+
+require_file "$SF_OUT/slimfly.topo" "SlimFly generator writes slimfly.topo"
+require_file "$SF_OUT/slimfly.adjlist" "SlimFly generator writes slimfly.adjlist"
+require_dir "$SF_OUT/fib" "SlimFly generator writes fib directory"
+require_dir "$SF_OUT/host_table" "SlimFly generator writes host_table directory"
+
+FIB_COUNT="$(ls "$SF_OUT"/fib/*.fib 2>/dev/null | wc -l | tr -d ' ')"
+HT_COUNT="$(ls "$SF_OUT"/host_table/*.lt 2>/dev/null | wc -l | tr -d ' ')"
+if [[ "$FIB_COUNT" -eq 18 && "$HT_COUNT" -eq 18 ]]; then
+    pass "SlimFly generator writes expected fib/host_table file counts for q=3"
+else
+    fail "SlimFly output counts (fib=$FIB_COUNT host_table=$HT_COUNT, expected 18/18)"
+fi
+
+cat >"$TMP_DIR/sf_1flow.tm" <<'EOF'
+Nodes 36
+Connections 1
+0->35 start 0 size 4096
+EOF
+
+"$SF_BIN" -topo "$SF_OUT" -routing SOURCE -tm "$TMP_DIR/sf_1flow.tm" >"$TMP_DIR/sf_run.out" 2>&1 || true
+if grep -q "Done" "$TMP_DIR/sf_run.out" && [[ "$(grep -c 'finished at' "$TMP_DIR/sf_run.out")" -eq 1 ]]; then
+    pass "SlimFly SOURCE end-to-end run succeeds with generated assets"
+else
+    fail "SlimFly SOURCE end-to-end run"
+fi
+
+echo "========================================="
+echo "Generator tests: PASS=$PASS FAIL=$FAIL"
+echo "========================================="
+
+if [[ "$FAIL" -gt 0 ]]; then
+    exit 1
+fi