Ruby Operation MongoDB (Advanced)-Create a database client connection

In Ruby's MongoDB2.4.3 driver version, build a ruby database connection by creating a Mongo::client object. The Mongo::client constructor is available in two ways: one by providing a host list and some optional parameters, and through a connection URI. Create a good database connection by default to the admin database.

1. Create a database client connection using Mongo::client

1.1. Single-server mode creating a database connection

To create a database connection in single-server mode, simply provide a host connection parameter. In addition, you can force the cluster topology to be converted to stand-alone mode by eliminating the Autodiscover step. You can create a database connection in single-server mode in the following three ways

Mongo::client.new ([' 127.0.0.1:27017 '],:d atabase=> ' mydb ')

Mongo::client.new ([' 127.0.0.1:27017 '],:d atabase=> ' mydb ',:connect=>:d irect)

Mongo::client.new (' Mongodb://127.0.0.1:27017/mydb ')

1.2. Replica set mode creating a database connection

By passing one or more host address parameters and replica set names, you can create a database connection to the replica set. Even if all the information for the replica set is not fully provided at the time of creation, the MongoDB drive's auto-Explore mode can find all the members in the replica set. Creating a database connection in a replica set can be created in the following form:

Mongo::client.new ([' 127.0.0.1:27017 ', ' 127.0.0.1:27018 '],:d atabase=> ' mydb ',:replica_set=> ' MyApp ')

Mongo::client.new (' Mongdb://127.0.0.1:27017,127.0.0.1:27018/mydb?replicaset=myapp ')

1.3. Share cluster mode to create a database connection

Create a shared cluster mode by passing one or more MONGOs hosts. The auto-Explore mode can qualify the server as a MONGOs instance, but if you turn off auto-discovery mode, pass the shared parameter to the connection to create the cluster-mode database connection. You can create a database connection by using the following three examples:

Mongo::client.new ([' 127.0.0.1:27017 '],:d atabase=> ' mydb ')

Mongo::client.new ([' 127.0.0.1:27017 '],:d atabase=> ' MyDB ',: connect=>:shared)

Mongo::client.new (' mongodb://127.0.0.1:27017/mydb?connect=shared ')

2. Database Client Connection parameter options

When using mongo::client, you can configure the behavior of the driver with several different optional parameters, either by configuring them in the constructor or by providing them to mongo::client through a URI.

This is not the standard format for Ruby, given that the URI's parameter setting requires camel formatting. The following table lists the parameter configuration options for URI format and the corresponding parameter options for using the Ruby constructor. When using both of these parameter settings, it is important to note that the option time unit in the URI parameter setting is milliseconds, whereas in the Ruby constructor, the second is the float type.

3. Uri parameters and corresponding Ruby parameters

URI Options	Ruby Options
Replicaset=string	: replica_set=>string
Connect=string	: Connect=>symbol
Ssl=boolean	: Ssl=>true|false
Connecttimeoutms=integer	: Connect_timeout=>float
Sockettimeoutms=integer	: Socket_timeout=>float
Serverselectiontimeoutms=integer	: Server_selection_timeout=>float
Localthresholdms=integer	: Local_threshold=>float
Maxpoolsize=integer	: Max_pool_size=>integer

Minpoolsize=integer	: Min_pool_size=>integer
Waitqueuetimeoutms=integer	: Wait_queue_timeout=>float
w=integer| String	{: write=>{:w=>integer| String}}
Wtimeoutms=integer	{: Write=>{:wtimeout=>float}}
Journal=boolean	{: Write=>{:j=>true|false}}
Fsync=boolean	{: Write =>{:fsync=>true|false}}
Readpreference=string	{: Read=>{:mode=>symbol}}
Readpreferencetags=string	{:read=>{:tag_sets=>array<string>}}

Authsource=string	: auth_source=>string
Authmechanism=string	: Auth_meth=>symbol
Authmechanismproperties=strings	{: Auth_mech_properties=>{:service_realm=>string,:canonicalize_host_name=>true|false,:service_name= >string}}

4. The role of each option in Ruby is explained in detail below, with default values and types

Parameters	Parameter description	Parameter type	Default value
: Replica_set	When using replica set mode, this parameter sets the name of the replica set and can filter the server by name when auto-discovery mode is enabled	String	None
: SSL	Notifies the client to connect to the server over SSL	Boolean	False
: Ssl_cert	Used to set the certificate file path, which is used to identify whether the authentication to a MONGODB connection is valid. If this option is set, it will have a higher usage priority than the value of: ssl_cret_string and: Ssl_sret_object value	String	None
: ssl_cert_string	The string field contains information about the certificate used to authenticate connection validity using PEM encoding. If this parameter is set, it has a higher usage priority than the value of: Ssl_cret_object	String	None
: Ssl_cert_object	Identify a connection to MongoDB using the Openssl::x509::certificate certificate	Openssl::x509::certificate	None
: Ssl_key	The private key file that identifies the connection validity. Although the secret key file is stored in the same file as the certificate, the two need to be precisely matched. If this parameter is set, it has a higher usage priority than: Ssl_key_string and: Ssl_key_object	String	None
: ssl_key_string	Contains information about using PEM-encoded private key strings for authentication of connection validity. If this parameter is set, it has a higher usage priority than: Ssl_key_object	String	None
: Ssl_key_object	Private key object for authentication of connection validity	OpenSSL::P Key	None
: Ssl_key_pass_phrase	Password information for the private key	String	None

: Ssl_ca_cert	A set of storage paths for certificate information that connects the authorization certificate to verify that the certificate will pass from the other end of the connection. Parameters: Ssl_verfiy need to be set: Ssl_ca_cret,:ssl_ca_cret_string,:ssl_ca_cret_object one of three parameters.	String	None
: ssl_ca_cert_string	A string that contains a set of certificate information that connects the authorization certificate for verifying that the certificate will pass from the other end of the connection. Parameters: Ssl_verfiy need to be set: Ssl_ca_cret,:ssl_ca_cret_string,:ssl_ca_cret_object one of three parameters.	String	None
: Ssl_ca_cert_object	Represents the openssl::x509::certificate array of certificate information that connects the authorization certificate, which is used to verify that the certificate will pass from the other end of the connection. Parameters: Ssl_verfiy need to be set: Ssl_ca_cret,:ssl_ca_cret_string,:ssl_ca_cret_object one of three parameters.	Array<openssl::x509::certificate>	None
: ssl_verify	Used to set whether peer certificate validation is performed	Boolean	False
: Connect_timeout	The wait time (in seconds) to create a socket connection before throwing an exception	Float	10 seconds
: Socket_timeout	The wait time (in seconds) before a socket execution operation throws an exception	Float	5 Seconds
: max_pool_size	The maximum number of connections for a single server connection pool	Integer	5
: min_pool_size	The minimum number of connections for a single server connection pool	Integer	1
: Wait_queue_timeout	Wait time waiting for connection in connection pool to become active	Float	1
: Write	Specify the parameters of the hash type associated with the write. The value can be: W,:wtimeout,:j,:fsync such as {: Write =>{: W=>2}}	Hash	{: w=>1}

: Read	A hash type parameter that sets the preferred read mode and the label collection for the selected server. Its value can be set to: Mode and: Tag_sets. For example {: read=>{: mode=>secondary,:tag_sets=>["Berlin"]}}	Hash	{: mode =:p Rimary}
: Auth_source	The authorization source information is set specifically	String	2.6 and later, if an authorization certificate is provided, the default is admin; otherwise, the current database
: Auth_mech	The authorization mechanism used for the specific settings. Can be one of the following values:: mongodb_cr,:mongodb_x509,:p Lain,:scram	Symbol	After the MongoDB3.0 version, if the user provided a qualification certificate but did not set: Auth_mech property, the default is: Scram. Prior to version 2.6, the default is: MONGODB_CR
: auth_mech_properties	Additional authorization mechanism properties are provided	Hash	None
: User	User name used for authentication	String	None
:p Assword	User password used for authentication	String	None
: Connect	Override the auto-Explore feature of the drive and force the cluster topology to be transformed into a specific type. Includes::d Irect,:replica_set or: Shared	Symbol	None
: heartbeat_frequency	Time for multiple monitors to flush server status asynchronously (in seconds)	Float	30
:d atabase	Database name that needs to be connected	String	Admin
: Server_selection_timeout	Select an appropriate server to perform certain operations, waiting time before throwing an exception	Float	30

: Local_threshold

Set the maximum latency for switching between the closest server and the server that can be selected

Float

0.015

5. Setting details for timeout related parameters

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Ruby Operation MongoDB (Advanced)-Create a database client connection