Mongodb 连接字符串中的参数清单配置选项

Represents a Connection String. The Connection String describes the hosts to be used and options.

The format of the Connection String is:

   mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database.collection][?options]]
 

• mongodb:// is a required prefix to identify that this is a string in the standard connection format.
• username:password@ are optional. If given, the driver will attempt to login to a database after connecting to a database server. For some authentication mechanisms, only the username is specified and the password is not, in which case the ":" after the username is left off as well
• host1 is the only required part of the connection string. It identifies a server address to connect to. Support for Unix domain sockets was added in 3.7. Note: The path must be urlencoded eg: mongodb://%2Ftmp%2Fmongodb-27017.sock and the jnr.unixsocket library installed.
• :portX is optional and defaults to :27017 if not provided.
• /database is the name of the database to login to and thus is only relevant if the username:password@ syntax is used. If not specified the "admin" database will be used by default.
• ?options are connection options. Note that if database is absent there is still a / required between the last host and the ? introducing the options. Options are name=value pairs and the pairs are separated by "&". For backwards compatibility, ";" is accepted as a separator in addition to "&", but should be considered as deprecated.

An alternative format, using the mongodb+srv protocol, is:

   mongodb+srv://[username:password@]host[/[database][?options]]
 

• mongodb+srv:// is a required prefix for this format.
• username:password@ are optional. If given, the driver will attempt to login to a database after connecting to a database server. For some authentication mechanisms, only the username is specified and the password is not, in which case the ":" after the username is left off as well
• host is the only required part of the URI. It identifies a single host name for which SRV records are looked up from a Domain Name Server after prefixing the host name with "_mongodb._tcp". The host/port for each SRV record becomes the seed list used to connect, as if each one were provided as host/port pair in a URI using the normal mongodb protocol.
• /database is the name of the database to login to and thus is only relevant if the username:password@ syntax is used. If not specified the "admin" database will be used by default.
• ?options are connection options. Note that if database is absent there is still a / required between the last host and the ? introducing the options. Options are name=value pairs and the pairs are separated by "&". For backwards compatibility, ";" is accepted as a separator in addition to "&", but should be considered as deprecated. Additionally with the mongodb+srv protocol, TXT records are looked up from a Domain Name Server for the given host, and the text value of each one is prepended to any options on the URI itself. Because the last specified value for any option wins, that means that options provided on the URI will override any that are provided via TXT records.

The following options are supported (case insensitive):

Server Selection Configuration:

• serverSelectionTimeoutMS=ms: How long the driver will wait for server selection to succeed before throwing an exception.
• localThresholdMS=ms: When choosing among multiple MongoDB servers to send a request, the driver will only send that request to a server whose ping time is less than or equal to the server with the fastest ping time plus the local threshold.

Server Monitoring Configuration:

• heartbeatFrequencyMS=ms: The frequency that the driver will attempt to determine the current state of each server in the cluster.

Replica set configuration:

• replicaSet=name: Implies that the hosts given are a seed list, and the driver will attempt to find all members of the set.

Connection Configuration:

• ssl=true|false: Whether to connect using TLS.
• tls=true|false: Whether to connect using TLS. Supersedes the ssl option
• tlsInsecure=true|false: If connecting with TLS, this option enables insecure TLS connections. Currently this has the same effect of setting tlsAllowInvalidHostnames to true. Other mechanism for relaxing TLS security constraints must be handled in the application by customizing the SSLContext
• sslInvalidHostNameAllowed=true|false: Whether to allow invalid host names for TLS connections.
• tlsAllowInvalidHostnames=true|false: Whether to allow invalid host names for TLS connections. Supersedes the sslInvalidHostNameAllowed option
• connectTimeoutMS=ms: How long a connection can take to be opened before timing out.
• socketTimeoutMS=ms: How long a send or receive on a socket can take before timing out.
• maxIdleTimeMS=ms: Maximum idle time of a pooled connection. A connection that exceeds this limit will be closed
• maxLifeTimeMS=ms: Maximum life time of a pooled connection. A connection that exceeds this limit will be closed

Connection pool configuration:

• maxPoolSize=n: The maximum number of connections in the connection pool.
• waitQueueTimeoutMS=ms: The maximum wait time in milliseconds that a thread may wait for a connection to become available.
• maxConnecting=n: The maximum number of connections a pool may be establishing concurrently.

Write concern configuration:

• safe=true|false
  • true: the driver ensures that all writes are acknowledged by the MongoDB server, or else throws an exception. (see also w and wtimeoutMS).
  • false: the driver does not ensure that all writes are acknowledged by the MongoDB server.
• journal=true|false
  • true: the driver waits for the server to group commit to the journal file on disk.
  • false: the driver does not wait for the server to group commit to the journal file on disk.
• w=wValue
  • The driver adds { w : wValue } to all write commands. Implies safe=true.
  • wValue is typically a number, but can be any string in order to allow for specifications like "majority"
• wtimeoutMS=ms
  • The driver adds { wtimeout : ms } to all write commands. Implies safe=true.
  • Used in combination with w

Read preference configuration:

• readPreference=enum: The read preference for this connection.
  • Enumerated values:
    • primary
    • primaryPreferred
    • secondary
    • secondaryPreferred
    • nearest
• readPreferenceTags=string. A representation of a tag set as a comma-separated list of colon-separated key-value pairs, e.g. "dc:ny,rack:1". Spaces are stripped from beginning and end of all keys and values. To specify a list of tag sets, using multiple readPreferenceTags, e.g. readPreferenceTags=dc:ny,rack:1;readPreferenceTags=dc:ny;readPreferenceTags=
  • Note the empty value for the last one, which means match any secondary as a last resort.
  • Order matters when using multiple readPreferenceTags.
• maxStalenessSeconds=seconds. The maximum staleness in seconds. For use with any non-primary read preference, the driver estimates the staleness of each secondary, based on lastWriteDate values provided in server hello responses, and selects only those secondaries whose staleness is less than or equal to maxStalenessSeconds. Not providing the parameter or explicitly setting it to -1 indicates that there should be no max staleness check. The maximum staleness feature is designed to prevent badly-lagging servers from being selected. The staleness estimate is imprecise and shouldn't be used to try to select "up-to-date" secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.

Authentication configuration:

• authMechanism=MONGO-CR|GSSAPI|PLAIN|MONGODB-X509: The authentication mechanism to use if a credential was supplied. The default is unspecified, in which case the client will pick the most secure mechanism available based on the sever version. For the GSSAPI and MONGODB-X509 mechanisms, no password is accepted, only the username.
• authSource=string: The source of the authentication credentials. This is typically the database that the credentials have been created. The value defaults to the database specified in the path portion of the connection string. If the database is specified in neither place, the default value is "admin". This option is only respected when using the MONGO-CR mechanism (the default).
• authMechanismProperties=PROPERTY_NAME:PROPERTY_VALUE,PROPERTY_NAME2:PROPERTY_VALUE2: This option allows authentication mechanism properties to be set on the connection string.
• gssapiServiceName=string: This option only applies to the GSSAPI mechanism and is used to alter the service name. Deprecated, please use authMechanismProperties=SERVICE_NAME:string instead.

Server Handshake configuration:

• appName=string: Sets the logical name of the application. The application name may be used by the client to identify the application to the server, for use in server logs, slow query logs, and profile collection.

Compressor configuration:

• compressors=string: A comma-separated list of compressors to request from the server. The supported compressors currently are 'zlib', 'snappy' and 'zstd'.
• zlibCompressionLevel=integer: Integer value from -1 to 9 representing the zlib compression level. Lower values will make compression faster, while higher values will make compression better.

General configuration:

• retryWrites=true|false. If true the driver will retry supported write operations if they fail due to a network error. Defaults to true.
• retryReads=true|false. If true the driver will retry supported read operations if they fail due to a network error. Defaults to true.
• uuidRepresentation=unspecified|standard|javaLegacy|csharpLegacy|pythonLegacy. See MongoClientSettings.getUuidRepresentation() for documentation of semantics of this parameter. Defaults to "javaLegacy", but will change to "unspecified" in the next major release.
• directConnection=true|false. If true the driver will set the connection to be a direct connection to the host.
• loadBalanced=true|false. If true the driver will assume that it's connecting to MongoDB through a load balancer.