Method expose

src/bvar/latency_recorder.cpp:191–263

}

int LatencyRecorder::expose(const butil::StringPiece& prefix1,
                            const butil::StringPiece& prefix2) {
    if (prefix2.empty()) {
        LOG(ERROR) << "Parameter[prefix2] is empty";
        return -1;
    }
    butil::StringPiece prefix = prefix2;
    // User may add "_latency" as the suffix, remove it.
    if (prefix.ends_with("latency") || prefix.ends_with("Latency")) {
        prefix.remove_suffix(7);
        if (prefix.empty()) {
            LOG(ERROR) << "Invalid prefix2=" << prefix2;
            return -1;
        }
    }
    std::string tmp;
    if (!prefix1.empty()) {
        tmp.reserve(prefix1.size() + prefix.size() + 1);
        tmp.append(prefix1.data(), prefix1.size());
        tmp.push_back('_'); // prefix1 ending with _ is good.
        tmp.append(prefix.data(), prefix.size());
        prefix = tmp;
    }

    // set debug names for printing helpful error log.
    _latency.set_debug_name(prefix);
    _latency_percentile.set_debug_name(prefix);

    if (_latency_window.expose_as(prefix, "latency") != 0) {
        return -1;
    }
    if (_max_latency_window.expose_as(prefix, "max_latency") != 0) {
        return -1;
    }
    if (_count.expose_as(prefix, "count") != 0) {
        return -1;
    }
    if (_qps.expose_as(prefix, "qps") != 0) {
        return -1;
    }
    char namebuf[32];
    snprintf(namebuf, sizeof(namebuf), "latency_%d", (int)FLAGS_bvar_latency_p1);
    if (_latency_p1.expose_as(prefix, namebuf, DISPLAY_ON_PLAIN_TEXT) != 0) {
        return -1;
    }
    snprintf(namebuf, sizeof(namebuf), "latency_%d", (int)FLAGS_bvar_latency_p2);
    if (_latency_p2.expose_as(prefix, namebuf, DISPLAY_ON_PLAIN_TEXT) != 0) {
        return -1;
    }
    snprintf(namebuf, sizeof(namebuf), "latency_%u", (int)FLAGS_bvar_latency_p3);
    if (_latency_p3.expose_as(prefix, namebuf, DISPLAY_ON_PLAIN_TEXT) != 0) {
        return -1;
    }
    if (_latency_999.expose_as(prefix, "latency_999", DISPLAY_ON_PLAIN_TEXT) != 0) {
        return -1;
    }
    if (_latency_9999.expose_as(prefix, "latency_9999") != 0) {
        return -1;