We are proud to announce that we have released HAProxy Data Plane API 2.8, available on our GitHub page.
This release follows the recent HAProxy 2.8 release and incorporates its changes, along with some improvements and changes specific to the API.
HAProxy Data Plane API 2.8 adds new keywords focused on QUIC, OCSP stapling, and tuning options that allow you to customize your HAProxy process using the HTTP REST API programmatically. This release also extends the Consul service discovery feature with options to customize which services you want to include in discovery, allow better control of their defaults, and integrate with Consul health checks.
Due to some licensing conflicts and for simplicity, we also removed the HCL configuration format for configuring the Data Plane API. From version 2.8 onwards, Data Plane API supports only the YAML format.
Extended HAProxy Configuration Keywords Support
Following the latest release of HAProxy, we are extending the configuration keyword support to support many new features in the load balancer.
/services/haproxy/configuration/binds endpoint gained the following options:
Signing algorithms, each separated by a colon, dictate the algorithms a client can use in the CertificateVerify message during authentication.
HAProxy 2.8 sets an ALPN value automatically. Setting this to true turns that off.
Sets the congestion control algorithm for QUIC listeners. It can be either cubic (the default) or newreno.
Signing algorithms, each separated by a colon, that HAProxy can use when signing the ephemeral public key during the TLS handshake.
Defines the threads on which a listener can run. It accepts a comma-separated list of thread ranges.
/services/haproxy/configuration/global endpoint gained the following options:
Defines a span of time over which to spread the closing of idle connections, rather than closing them all at once. This option accepts an integer, in milliseconds.
Defines an ASCII string secret used to derive stateless reset tokens for QUIC connections. When not set, the value is random.
Turns off the DNS resolvers section used by the Lua HTTP client. HAProxy generates this resolvers section automatically, which parses the
Sets the name of the resolvers section the Lua HTTP client should use. By default, it tries the resolvers section named
Changes the preferred address version. By default, the Lua HTTP client prefers IPv6 addresses from DNS records. You can set this to either ipv4 or ipv6.
Sets the path to a CA file the Lua HTTP client uses to verify the server certificate of the HTTP service it connects to when that service is hosted over HTTPS. This might be necessary if the server certificate is not already trusted because its chained CA is unknown.
Disables verification of the server certificate of the service the Lua HTTP client is connecting to. This option accepts a value of none or required.
Globally turns off the QUIC transport protocol. Any configured QUIC listeners will not bind to their addresses. Set this to true or false.
Opens the maximum file descriptor, which pre-allocates the kernel's data structures. Set this to true or false.
Sets the global default for the signing algorithms clients can use in their CertificateVerify messages during authentication. Separate each algorithm by a colon.
Sets the global default for the signing algorithms HAProxy can use when signing the ephemeral public key during the TLS handshake. Separate each algorithm by a colon.
Sets the initial window size for outgoing HTTP/2 connections. Set this to a number of bytes.
Sets the maximum number of concurrent streams per outgoing HTTP/2 connection.
Sets the initial window size for incoming HTTP/2 connections. Set this to a number of bytes.
Sets the maximum number of concurrent streams per incoming HTTP/2 connection. It applies to outgoing connections too, when
Sets the strategy by which a listener is sharded (a shortcut for defining multiple listeners for the same address). It accepts a value of by-process, by-thread, or by-group.
Sets a timeout for how long a Lua script can execute without yielding control back to the HAProxy process. Other timeouts exist for the total execution time of a script across yields. Set this to a number of milliseconds.
Sets the amount of memory to keep hot in the local cache for each thread. The default is 512 KB. It accepts a number of bytes.
Sets the maximum number of buffers allocated for a QUIC connection. The default is 30.
Sets a timeout for idle QUIC connections in milliseconds for frontends. The default is 30 seconds.
Sets the initial maximum number of bidirectional streams the remote peer will be authorized to open, which determines the number of concurrent client requests. The default is 100.
QUIC is transported over the UDP protocol, which ordinarily would not guarantee message delivery. But QUIC does have loss detection and will retransmit lost frames. This setting counts the number of retransmissions and closes the connection if the limit has been reached. The default is 10.
Sets a threshold on the number of half-opened QUIC connections, which, if reached, dynamically enables the Retry feature. The default is 100.
Sets the strategy by which QUIC connections use sockets to send and receive messages. Set this to either connection (the default) to allocate a socket per connection or listener to share a socket.
Sets the maximum interval in seconds between two automatic updates of the same OCSP response. It defaults to 1 hour.
Sets the minimum interval in seconds between two automatic updates of the same OCSP response. It defaults to 5 minutes.
Changes the number of stick table counters available. It defaults to 3.
/services/haproxy/configuration/http_request_rules endpoint gained the following options for its
/services/haproxy/configuration/http_after_response_rules endpoint gained the following options for its
/services/haproxy/configuration/tcp_request_rules endpoint gained the following options for its
/services/haproxy/configuration/tcp_response_rules endpoint also gained the above actions.
Extend Consul Service Discovery Options
If you are using Consul to discover your services, you can use the Data Plane API to dynamically configure HAProxy from changes in Consul's services registry. You can use the
/service_discovery/consul endpoint to set up parameters for the Data Plane API to connect to the Consul API and read Consul service discovery information. Read our blog post Consul Service Discovery for HAProxy, for an introduction to this topic.
In HAProxy Data Plane API 2.8, we’ve extended that feature with several new options to enable greater flexibility with your Consul integration.
We’ve added the
defaults field, with which you can select a specific
defaults section by its name from which the generated backends that represent Consul services will inherit settings. This option allows you to have different
defaults sections for Consul service discovery, separated from other load balanced applications, for more flexibility in setting their other options.
In the snippet below of a configuration generated by the API, the
backend section has inherited settings from the
defaults section named consul:
timeout connect 5s
timeout client 30s
timeout server 10s
//autogenerated consul backend from consul
backend consul-backend-127.0.0.1-80-test from consul
Also, we’ve added two new fields that consider Consul health checks:
health_check_policy and the
health_check_policy_min. These fields allow you to define the health check conditions for each node in service for that node to be considered valid and configured as a backend server in the HAProxy configuration. You can define four different health check policies:
All the nodes for a service reported by Consul API are considered valid and will be configured. This is the default behavior.
A node is considered valid if any of the configured health checks is reporting passing on the Consul API.
A node is considered valid if all of the configured health checks are reporting passing on the Consul API.
A node is considered valid if the number of passing health checks is greater or equal to the
In addition to those changes, we’ve added
service_name_regexp to allow for more programmability in our Consul service discovery feature. This regular expression filters the reported services from the Consul API by their name. Only the services that match the given regular expression will be considered and configured in the HAProxy configuration file.
Breaking Change: Removing HCL Configuration Format
You can configure HAProxy Data Plane API using its configuration file. We support HCL and YAML file formats, so you can choose either. Due to the licensing conflict with libraries used to parse the HCL file format, we decided to stick with only one file format: YAML. It’s widely used and easy to read and write manually. So, for simplicity, we have removed the support for the HCL configuration file.
To ease the migration for users currently using the HCL configuration file format, we published a tool that converts a Data Plane API configuration file from HCL to YAML. You can find the HCL-to-YAML conversion tool here.
After unpacking the binary from the archive, you can do the following:
hcl-converter dataplaneapi.hcl dataplaneapi.yml
On successful conversion, it will print out the following output:
Input file: dataplaneapi.hcl
Output file: dataplaneapi.yaml
Library Updates and Bug Fixes
In addition to the other changes, HAProxy Data Plane API 2.8 introduces stability and infrastructure improvements and bug fixes.
One of the bigger updates is that the Data Plane API project has been migrated to Go 1.20 along with the underlying libraries, config-parser, and client-native. This migration allows us to improve our codebase with all the new features, optimizations, and security fixes of Go 1.20.
In addition, we scanned all external dependencies and updated Data Plane API’s external libraries for bug and security fixes.
There have been 56 commits of bug fixes in the Data Plane API project and its underlying libraries since the v2.7.0 release.
Conclusion & Contributors
BUG | FEATURE | TEST
BUG | BUILD | FEATURE
BUILD | FEATURE
BUG | BUILD | FEATURE | TEST
BUG | BUILD | DOCUMENTATION | FEATURE
BUG | FEATURE
BUG | BUILD | FEATURE
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