Add C Client examples

developing-with-nats/security/creds.md

@@ -88,5 +88,28 @@ let nc = await connect({
 });
 ```
 {% endtab %}
+
+{% tab title="C" %}
+```c
+natsConnection      *conn      = NULL;
+natsOptions         *opts      = NULL;
+natsStatus          s          = NATS_OK;
+
+s = natsOptions_Create(&opts);
+if (s == NATS_OK)
+    // Pass the credential file this way if the file contains both user JWT and seed.
+    // Otherwise, if the content is split, the first file is the user JWT, the second
+    // contains the seed.
+    s = natsOptions_SetUserCredentialsFromFiles(opts, "path_to_creds_file", NULL);
+if (s == NATS_OK)
+    s = natsConnection_Connect(&conn, opts);
+
+(...)
+
+// Destroy objects that were created
+natsConnection_Destroy(conn);
+natsOptions_Destroy(opts);
+```
+{% endtab %}
 {% endtabs %}
 

developing-with-nats/security/nkey.md

@@ -105,5 +105,45 @@ let nc = await connect({
 });
 ```
 {% endtab %}
+
+{% tab title="C" %}
+```c
+static natsStatus
+sigHandler(
+    char            **customErrTxt,
+    unsigned char   **signature,
+    int             *signatureLength,
+    const char      *nonce,
+    void            *closure)
+{
+    // Sign the given `nonce` and return the signature as `signature`.
+    // This needs to allocate memory. The length of the signature is
+    // returned as `signatureLength`.
+    // If an error occurs the user can return specific error text through
+    // `customErrTxt`. The library will free this pointer.
+
+    return NATS_OK;
+}
+
+(...)
+
+natsConnection      *conn      = NULL;
+natsOptions         *opts      = NULL;
+natsStatus          s          = NATS_OK;
+const char          *pubKey    = "my public key......";
+
+s = natsOptions_Create(&opts);
+if (s == NATS_OK)
+    s = natsOptions_SetNKey(opts, pubKey, sigHandler, NULL);
+if (s == NATS_OK)
+    s = natsConnection_Connect(&conn, opts);
+
+(...)
+
+// Destroy objects that were created
+natsConnection_Destroy(conn);
+natsOptions_Destroy(opts);
+```
+{% endtab %}
 {% endtabs %}
 

developing-with-nats/security/tls.md

@@ -203,6 +203,28 @@ let nc = await connect({
 });
 ```
 {% endtab %}
+
+{% tab title="C" %}
+```c
+natsConnection      *conn      = NULL;
+natsOptions         *opts      = NULL;
+natsStatus          s          = NATS_OK;
+
+s = natsOptions_Create(&opts);
+if (s == NATS_OK)
+    s = natsOptions_SetCertificatesChain(opts, "client-cert.pem", "client-key.pem");
+if (s == NATS_OK)
+    s = natsOptions_SetCATrustedCertificates(opts, "rootCA.pem");
+if (s == NATS_OK)
+    s = natsConnection_Connect(&conn, opts);
+
+(...)
+
+// Destroy objects that were created
+natsConnection_Destroy(conn);
+natsOptions_Destroy(opts);
+```
+{% endtab %}
 {% endtabs %}
 
 ## Connecting with the TLS Protocol

developing-with-nats/security/token.md

@@ -69,6 +69,26 @@ end
 let nc = await connect({url: server.nats, token: "mytoken"});
 ```
 {% endtab %}
+
+{% tab title="C" %}
+```c
+natsConnection      *conn      = NULL;
+natsOptions         *opts      = NULL;
+natsStatus          s          = NATS_OK;
+
+s = natsOptions_Create(&opts);
+if (s == NATS_OK)
+    s = natsOptions_SetToken(opts, "mytoken");
+if (s == NATS_OK)
+    s = natsConnection_Connect(&conn, opts);
+
+(...)
+
+// Destroy objects that were created
+natsConnection_Destroy(conn);
+natsOptions_Destroy(opts);
+```
+{% endtab %}
 {% endtabs %}
 
 ## Connecting with a Token in the URL
@@ -134,5 +154,25 @@ let url = `nats://:mytoken@127.0.0.1:${port}`;
 let nc = await connect({url: url});
 ```
 {% endtab %}
+
+{% tab title="C" %}
+```c
+natsConnection      *conn      = NULL;
+natsOptions         *opts      = NULL;
+natsStatus          s          = NATS_OK;
+
+s = natsOptions_Create(&opts);
+if (s == NATS_OK)
+    s = natsOptions_SetURL(opts, "nats://mytoken@127.0.0.1:4222");
+if (s == NATS_OK)
+    s = natsConnection_Connect(&conn, opts);
+
+(...)
+
+// Destroy objects that were created
+natsConnection_Destroy(conn);
+natsOptions_Destroy(opts);
+```
+{% endtab %}
 {% endtabs %}
 

developing-with-nats/security/userpass.md

@@ -93,6 +93,26 @@ end
 let nc = await connect({url: server.nats, user: "myname", pass: "password"});
 ```
 {% endtab %}
+
+{% tab title="C" %}
+```c
+natsConnection      *conn      = NULL;
+natsOptions         *opts      = NULL;
+natsStatus          s          = NATS_OK;
+
+s = natsOptions_Create(&opts);
+if (s == NATS_OK)
+    s = natsOptions_SetUserInfo(opts, "myname", "password");
+if (s == NATS_OK)
+    s = natsConnection_Connect(&conn, opts);
+
+(...)
+
+// Destroy objects that were created
+natsConnection_Destroy(conn);
+natsOptions_Destroy(opts);
+```
+{% endtab %}
 {% endtabs %}
 
 ## Connecting with a User/Password in the URL
@@ -172,5 +192,25 @@ let url = `nats://myname:password@127.0.0.1:${port}`;
 let nc = await connect({url: url});
 ```
 {% endtab %}
+
+{% tab title="C" %}
+```c
+natsConnection      *conn      = NULL;
+natsOptions         *opts      = NULL;
+natsStatus          s          = NATS_OK;
+
+s = natsOptions_Create(&opts);
+if (s == NATS_OK)
+    s = natsOptions_SetURL(opts, "nats://myname:password@127.0.0.1:4222");
+if (s == NATS_OK)
+    s = natsConnection_Connect(&conn, opts);
+
+(...)
+
+// Destroy objects that were created
+natsConnection_Destroy(conn);
+natsOptions_Destroy(opts);
+```
+{% endtab %}
 {% endtabs %}