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GetEndpoints (C)

前置 / 配套

API​

DARRA_OPCUA_API DarraUa_Status DARRA_OPCUA_CALL DarraUa_Discovery_GetEndpoints(
    const char*                    endpoint_url,
    uint32_t                       timeout_ms,
    DarraUa_GetEndpointsResult**   out_result);

DARRA_OPCUA_API uint32_t DARRA_OPCUA_CALL
DarraUa_GetEndpointsResult_GetCount(const DarraUa_GetEndpointsResult* r);

DARRA_OPCUA_API const DarraUa_EndpointDescription* DARRA_OPCUA_CALL
DarraUa_GetEndpointsResult_GetEndpoint(
    const DarraUa_GetEndpointsResult* r, uint32_t index);

DARRA_OPCUA_API void DARRA_OPCUA_CALL
DarraUa_GetEndpointsResult_Delete(DarraUa_GetEndpointsResult* r);

通过临时 SecureChannel (None mode) 连服务端, 拉 Endpoint 列表后立即断开. 不需要 Session.

EndpointDescription 字段​

typedef struct {
    char*    endpoint_url;
    char*    security_policy_uri;
    int32_t  security_mode;                 /* DarraUa_MessageSecurityMode */
    char*    server_application_uri;
    char*    server_product_uri;
    char*    server_application_name;       /* LocalizedText.text */
    int32_t  server_application_type;       /* 0=Server 1=Client 2=ClientAndServer 3=DiscoveryServer */
    uint8_t* server_certificate;            /* DER, 可为 NULL */
    int32_t  server_certificate_len;
    char*    transport_profile_uri;
    uint8_t  security_level;
    uint8_t  _pad[3];
    int32_t  user_token_count;
    char**   user_token_policy_ids;
    int32_t* user_token_types;              /* 0=Anonymous 1=Username 2=Certificate 3=IssuedToken */
} DarraUa_EndpointDescription;

所有指针字段由 Stack 在 GetEndpoints 内部分配, 由 DarraUa_GetEndpointsResult_Delete 统一释放, 调用方不要单独 free.

完整示例​

#include <darra_opcua/darra_opcua.h>
#include <stdio.h>

int main(int argc, char** argv)
{
    const char* url = (argc >= 2) ? argv[1] : "opc.tcp://localhost:4840";
    DarraUa_Initialize();

    DarraUa_GetEndpointsResult* res = NULL;
    DarraUa_Status st = DarraUa_Discovery_GetEndpoints(url, 5000, &res);
    if (!DARRA_UA_STATUS_IS_GOOD(st)) {
        fprintf(stderr, "GetEndpoints failed: 0x%08X (%s)\n",
                (unsigned)st, DarraUa_StatusName(st));
        DarraUa_Shutdown();
        return 1;
    }

    uint32_t n = DarraUa_GetEndpointsResult_GetCount(res);
    printf("Server has %u endpoints:\n", (unsigned)n);

    for (uint32_t i = 0; i < n; ++i) {
        const DarraUa_EndpointDescription* ep =
            DarraUa_GetEndpointsResult_GetEndpoint(res, i);
        if (!ep) continue;

        printf("\n  URL:    %s\n", ep->endpoint_url);
        printf("  Mode:   %d\n", ep->security_mode);
        printf("  Policy: %s\n", ep->security_policy_uri);
        printf("  Tokens: %d\n", ep->user_token_count);
        for (int t = 0; t < ep->user_token_count; ++t) {
            printf("    - type=%d policy_id=%s\n",
                   ep->user_token_types[t],
                   ep->user_token_policy_ids[t]);
        }
    }

    DarraUa_GetEndpointsResult_Delete(res);
    DarraUa_Shutdown();
    return 0;
}

典型输出​

Server has 4 endpoints:

  URL:    opc.tcp://server:4840
  Mode:   1 (None)
  Policy: http://opcfoundation.org/UA/SecurityPolicy#None
  Tokens: 1
    - type=0 policy_id=anonymous

  URL:    opc.tcp://server:4840
  Mode:   3 (SignAndEncrypt)
  Policy: http://opcfoundation.org/UA/SecurityPolicy#Basic256Sha256
  Tokens: 2
    - type=1 policy_id=username
    - type=2 policy_id=certificate

服务端通常暴露多个组合 (None / Sign / SignAndEncrypt × Anonymous / Username / Certificate), 客户端按需求挑.

错误码​

状态码含义
DARRA_UA_STATUS_BAD_COMMUNICATION_ERROR网络 / 服务端不可达
DARRA_UA_STATUS_BAD_TIMEOUTtimeout_ms 内未收到响应
DARRA_UA_STATUS_BAD_TCP_ENDPOINT_URL_INVALIDURL 格式错
DARRA_UA_STATUS_BAD_SERVICE_UNSUPPORTED服务端不支持 (罕见)

下一步​