override fun prepareRequest()

in anthropic-java-bedrock/src/main/kotlin/com/anthropic/bedrock/backends/BedrockBackend.kt [126:190]
51 lines of code
6 McCabe index (conditional complexity)

    override fun prepareRequest(request: HttpRequest): HttpRequest {
        val pathSegments = request.pathSegments

        if (pathSegments.isEmpty()) {
            throw AnthropicInvalidDataException("Request missing all path segments.")
        }

        require(pathSegments[0] != "model") { "Request already prepared for Bedrock." }

        if (pathSegments[0] != "v1") {
            throw AnthropicInvalidDataException("Expected first 'v1' path segment.")
        }

        if (pathSegments.size <= 1) {
            throw AnthropicInvalidDataException("Missing service name from request URL.")
        }

        when (pathSegments[1]) {
            "messages" -> {
                if (pathSegments.size > 2) {
                    when (pathSegments[2]) {
                        "batches" ->
                            throw AnthropicException("Batch API is not supported for Bedrock.")
                        "count_tokens" ->
                            throw AnthropicException("Token counting is not supported for Bedrock.")
                    } // For now, ignore any other path segments.
                }
            }
            "complete" -> {
                // Do nothing special.
            }
            else ->
                throw AnthropicException(
                    "Service is not supported for Bedrock: ${pathSegments[1]}."
                )
        }

        val jsonBody: ObjectNode =
            bodyToJson(jsonMapper, request.body)
                ?: throw AnthropicInvalidDataException("Request has no body")

        jsonBody.put("anthropic_version", ANTHROPIC_VERSION)

        val betaVersions =
            request.headers.values(HEADER_ANTHROPIC_BETA).flatMap { it.split(",") }.distinct()

        if (betaVersions.isNotEmpty()) {
            jsonBody.replace("anthropic_beta", jsonMapper.valueToTree(betaVersions))
        }

        val model =
            jsonBody.remove("model")
                ?: throw AnthropicInvalidDataException("No model found in body.")
        val modelId = model.asText()
        // For Bedrock, the "stream" property must be removed from the body.
        // This differs from Vertex where the property is retained.
        val isStream = jsonBody.remove("stream")?.asBoolean() ?: false

        return request
            .toBuilder()
            .replaceAllPathSegments("model", modelId)
            .addPathSegment(if (isStream) "invoke-with-response-stream" else "invoke")
            .body(json(jsonMapper, jsonBody))
            .build()
    }