I am setting up Go with Neo4j on a live project for one of the microservices
I went through the docs around setting up the same but it does not show the best practice to do the same (specifically globally and pass around the session instance throughout the application)
This is what I am doing to setup the same, was wondering if this is the right approach:
// app.go
import ""github.com/neo4j/neo4j-go-driver/neo4j""
type App struct {
Router *mux.Router
DB *sqlx.DB
Neo4j neo4j.Session // setting neo4j session globally for injection
}
// =============================
// Neo4j initialization
// =============================
driver, err2 := neo4j.NewDriver(
neo4jConfig.connstring,
neo4j.BasicAuth(neo4jConfig.username, neo4jConfig.password, ""),
func(c *neo4j.Config){
c.Encrypted = false
},
)
checkForErrors(err2, "Cannot connect to NEO4J")
defer driver.Close()
session, err3 := driver.NewSession(neo4j.SessionConfig{})
a.Neo4j = session // 👈 assigning the session instance
Now this will be injected as a dependency in the repo package where the queries are being executed
The example in the readme says the following:
// Sessions are short-lived, cheap to create and NOT thread safe. Typically create one or more sessions
// per request in your web application. Make sure to call Close on the session when done.
// For multi-database support, set sessionConfig.DatabaseName to requested database
// Session config will default to write mode, if only reads are to be used configure session for
// read mode.
session := driver.NewSession(neo4j.SessionConfig{})
So having a global driver instance is not an issue, but you should not be using a global session instance since it is not thread safe.
I use restlet client to send rest request to the server.
public class RestHandler {
protected ClientResource resource = null;
protected Client client = null;
public void connect(final String address,
final Protocol protocol){
final Context context = new Context();
if (client == null) {
logger.info("Create Client.");
client = new Client(context, protocol);
}
resource = new ClientResource(context, new Reference(protocol, address));
resource.setNext(client);
resource.setEntityBuffering(true);
}
}
In its child class, use resource.get()/post/put/delete to send rest request.
I found the response come back so slow at the first time(5-10s).
And then it go faster in the next few requests.
But after waiting about 10min I send the request again, it become slow again.
Is there any way to make the response come back faster?
You can try to use another client connector. It can be the cause of your problem, especially if you use the default one. Notice that the default one should be used for development only.
This page gives you all the available client connectors: http://restlet.com/technical-resources/restlet-framework/guide/2.3/core/base/connectors.
Regarding client connectors, you can configure properties to tune them. To use a client connector, simply put the corresponding Restlet extension within your classpath. Perhaps can you make a try with the extension org.restlet.ext.httpclient.
This answer could help you regarding connector configuration and properties: Restlet HTTP Connection Pool.
Hope it helps you,
Thierry
In my gwt web-app i'm using Mondrian. I have a method:
private Result executeMdxQuery(String queryString, Schema schema) throws InterruptedException {
CatalogLocatorImpl locator = new CatalogLocatorImpl();
Connection mdxConnection = DriverManager.getConnection(createConnectString(schema), locator);
return executeMdxQuery(queryString, mdxConnection);
}
result of createConnectString(schema) is
Provider=mondrian;Jdbc=jdbc:mysql://localhost/dds?user=root&password=qwerty;Catalog=/home/vskovalenko/schemas/air_new_zealand_monthly_traffic.xml;JdbcDrivers=com.mysql.jdbc.Driver;
all data within it is seems to be correct (at least db credentials and path to the file), this method throws no exception, it just silently dies and doesn't tell anything. Where should i loock to?
You should use the olap4j API to get a connection. This will allow you to let the application server manage and pool the connections to Mondrian.
If you require more control on the Mondrian server instance, you should take a look at the class MondrianServer.
add the following snippet to your code and try again:
Class.forName("mondrian.olap4j.MondrianOlap4jDriver");
I'm using H2 database console as a servlet in my own web application that provides a front end of many databases.
How to skip or help a login step at H2 database console by passing some parameters in my own code?
(I have many databases, so I won't use "saved settings" first.)
imaginary: http://myapp/h2console/login.do?user=scott&password=tiger&url=jdbc:thin:......
Because of the somewhat special session handling of the console, this is not possible just using an fixed URL. (The session handling allows to open multiple connections within multiple tabs from one browser, which is not possible when using cookies.)
However, what you can do is create a URL in the same way as Server.startWebServer(Connection conn) does:
// the server is already running in your case,
// so most likely you don't need the following lines:
WebServer webServer = new WebServer();
Server web = new Server(webServer, new String[] { "-webPort", "0" });
web.start();
Server server = new Server();
server.web = web;
webServer.setShutdownHandler(server);
// this will create a new session and return the URL for it:
String url = webServer.addSession(conn);
I have a proxy object generated by Visual Studio (client side) named ServerClient. I am attempting to set ClientCredentials.UserName.UserName/Password before opening up a new connection using this code:
InstanceContext context = new InstanceContext(this);
m_client = new ServerClient(context);
m_client.ClientCredentials.UserName.UserName = "Sample";
As soon as the code hits the UserName line it fails with an "Object is read-only" error. I know this can happen if the connection is already open or faulted, but at this point I haven't called context.Open() yet.
I have configured the Bindings (which uses netTcpBinding) to use Message as it's security mode, and MessageClientCredentialType is set to UserName.
Any ideas?
I noticed that after creating an instance of the proxy class for the service, I can set the Username and Password once without errors and do a successful call to my webservice. When I then try to set the Username and Password again on the existing instance (unnecessary of course) I get the 'Object is Read-Only' error you mentioned. Setting the values once per instance lifetime worked for me.
It appears that you can only access these properties pretty early in the instanciation cycle. If I override the constructor in the proxy class (ServerClient), I'm able to set these properties:
base.ClientCredentials.UserName.UserName = "Sample";
I'm beginning to appreciate the people who suggest not using the automatically built proxies provided by VS.
here is the solution:
using SysSvcmod = System.ServiceModel.Description;
SysSvcmod.ClientCredentials clientCredentials = new SysSvcmod.ClientCredentials();
clientCredentials.UserName.UserName = "user_name";
clientCredentials.UserName.Password = "pass_word";
m_client.ChannelFactory.Endpoint.Behaviors.RemoveAt(1);
m_client.ChannelFactory.Endpoint.Behaviors.Add(clientCredentials);
I have similar code that's passing UserName fine:
FooServiceClient client = new FooServiceClient("BasicHttpBinding_IFooService");
client.ClientCredentials.UserName.UserName = "user";
client.ClientCredentials.UserName.Password = "password";
Try creating the proxy with binding name in app.config.
The correct syntax is:
// Remove the ClientCredentials behavior.
client.ChannelFactory.Endpoint.Behaviors.Remove<ClientCredentials>();
// Add a custom client credentials instance to the behaviors collection.
client.ChannelFactory.Endpoint.Behaviors.Add(new MyClientCredentials());
http://msdn.microsoft.com/en-us/library/ms730868.aspx
It worked for me.
I was facing same problem, my code started working when I changed my code i.e. assigning values to Client credential immediately after initializing Client object.
here is the solution ,
ProductClient Manager = new ProductClient();
Manager.ClientCredentials.UserName.UserName = txtUserName.Text;
Manager.ClientCredentials.UserName.Password = txtPassword.Text;
This will not happen if the service reference is added through -> Add service reference ->Advanced->Add Web Reference-> Url/wsdl (local disk file).
I was facing this issue where I was trying to create a generic method to create a clients for different end points.
Here how I achieved this.
public static T CreateClient<T>(string url) where T : class
{
EndpointAddress endPoint = new EndpointAddress(url);
CustomBinding binding = CreateCustomBinding();
T client = (T)Activator.CreateInstance(typeof(T), new object[] { binding, endPoint });
SetClientCredentials(client);
return client;
}
public static void SetClientCredentials(dynamic obj)
{
obj.ChannelFactory.Endpoint.Behaviors.Remove<ClientCredentials>();
obj.ChannelFactory.Endpoint.Behaviors.Add(new CustomCredentials());
obj.ClientCredentials.UserName.UserName = "UserId";
obj.ClientCredentials.UserName.Password = "Password";
}
I think your problem might be related to the use of the InstanceContext. I thought that was only needed for duplex communication channels from the server side.
I admit I'm not sure about this, but I think in this case you are telling the client to use an existing instance context so it thinks there is already a running service and will not allow changes.
What is driving the use of InstanceContext?
If using a duplex client, when you instantiate it the DuplexChannelFactory within the DuplexClientBase that your client is derived from is initialized with existing credentials so it can open the callback channel, which is why the credentials would be read only.
I second Mike's question and also ask why are you using NetTcpBinding if you are not going to use its inherent transport level security? Perhaps an HTTP based binding would be a better fit? That would allow you to use certificate based security which I believe can be modified after instantiation (http://msdn.microsoft.com/en-us/library/ms576164.aspx).
A shot in the dark but does netTcpBinding allow username and password validation? Try using application layer (SOAP) security using a http binding
or you could just simply check the Credentials
if (client.ClientCredentials.ClientCertificate.Certificate == null || string.IsNullOrEmpty(client.ClientCredentials.ClientCertificate.Certificate.Thumbprint))
{
client.ClientCredentials.ClientCertificate.SetCertificate(
StoreLocation.LocalMachine,
StoreName.My,
X509FindType.FindByThumbprint, ConfigurationManager.AppSettings.Get("CertificateThumbprint"));
}
In .NET 4.6 I couldn't remove the credentials using Fabienne's answer. Kept getting Compiler Error CS0308 in the Remove method. What worked for me was this:
Type endpointBehaviorType = serviceClient.ClientCredentials.GetType();
serviceClient.Endpoint.EndpointBehaviors.Remove(endpointBehaviorType);
ClientCredentials clientCredentials = new ClientCredentials();
clientCredentials.UserName.UserName = userName;
clientCredentials.UserName.Password = password;
serviceClient.Endpoint.EndpointBehaviors.Add(clientCredentials);