Configure the Java Client

RepostClient.create() reads the environment. To configure explicitly, build ClientOptions and pass it to create(ClientOptions):

ClientOptions options = ClientOptions.builder()
        .apiKey(System.getenv("REPOST_SEND_API_KEY"))
        .baseUri("https://api.repost.sh")
        .operationTimeout(Duration.ofSeconds(30))
        .maxAttempts(4)
        .maxInFlightOperations(128)
        .build();
return RepostClient.create(options);

Credential and endpoint precedence

Credential precedence, highest first: a .apiKeyProvider(...) (resolved per send) → a fixed .apiKey(...) → the REPOST_SEND_API_KEY environment variable → the REPOST_TOKEN environment variable. With none set, the first send fails with a CONFIGURATION error and never touches the network. Base URI: an explicit .baseUri(...) → REPOST_API_URL → the default https://api.repost.sh. Plain http:// is accepted only for loopback hosts.

Defaults

The defaults are production-ready:

Option	Default	Notes
`connectTimeout`	10s	Connection establishment.
`attemptTimeout`	30s	One HTTP attempt.
`operationTimeout`	120s	Whole operation, including retries — the one deadline that bounds a send.
`maxAttempts`	4	1–10. Transport attempts before giving up.
`retryBaseDelay` / `retryMaxDelay`	250ms / 60s	Exponential backoff with jitter.
`maxInFlightOperations`	256	1–65536. Bounded admission — see Reliability.
`maxBufferedBytes`	64 MiB	4 MiB–1 GiB. Aggregate request/response byte budget.

ClientOptions.toString() is redacted — it never prints your credential.

Proxy, TLS, and mTLS

Build HttpTransportOptions and pass it via .httpTransportOptions(...): an explicit HttpProxyOptions (with an optional credentials provider), a borrowed SSLContext for a custom truststore or mutual TLS, and an allowlisted TLS protocol (TLS 1.2/1.3) and cipher list. HTTP redirects are disabled.

Continue

Reliability

Idempotency, the five delivery states, cancellation, and backpressure.

Observability

Diagnostics, lifecycle observers, Micrometer, and OpenTelemetry.

Frameworks

Spring Boot properties, Jakarta CDI config, and container lifecycle.

Send

Schema

Publishing

Delivery

Customer experience

TypeScript

Go

C#

Python

Java

Kotlin

Configure the Java Client

Credential and endpoint precedence

Defaults

Proxy, TLS, and mTLS

Continue

Reliability

Observability

Frameworks

​Credential and endpoint precedence

​Defaults

​Proxy, TLS, and mTLS

​Continue

Reliability

Observability

Frameworks

Credential and endpoint precedence

Defaults

Proxy, TLS, and mTLS

Continue