com.gocardless.http.IdempotentPostRequest Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of gocardless-pro Show documentation

Client library for accessing the GoCardless Pro API

There is a newer version: 6.0.0

package com.gocardless.http;

import com.gocardless.errors.ApiError;
import com.gocardless.errors.InvalidStateException;
import com.google.common.base.Optional;
import com.google.common.base.Predicate;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Iterables;
import java.util.UUID;

public abstract class IdempotentPostRequest extends PostRequest {
    private static final Predicate CONFLICT_ERROR = new Predicate() {
        @Override
        public boolean apply(ApiError error) {
            return error.getReason().equals("idempotent_creation_conflict");
        }
    };
    private transient String idempotencyKey;

    protected IdempotentPostRequest(HttpClient httpClient) {
        super(httpClient);
    }

    /**
     * Executes this request.
     *
     * Returns the response entity.
     *
     * @throws com.gocardless.GoCardlessException
     */
    @Override
    public T execute() {
        try {
            return getHttpClient().executeWithRetries(this);
        } catch (InvalidStateException e) {
            Optional conflictError = Iterables.tryFind(e.getErrors(), CONFLICT_ERROR);
            if (conflictError.isPresent() && !getHttpClient().isErrorOnIdempotencyConflict()) {
                String id = conflictError.get().getLinks().get("conflicting_resource_id");
                return handleConflict(getHttpClient(), id).execute();
            } else {
                throw Throwables.propagate(e);
            }
        }
    }

    protected void setIdempotencyKey(String idempotencyKey) {
        this.idempotencyKey = idempotencyKey;
    }

    @Override
    protected final ImmutableMap getHeaders() {
        String requestIdempotencyKey;
        if (this.idempotencyKey == null) {
            requestIdempotencyKey = UUID.randomUUID().toString();
            this.setIdempotencyKey(requestIdempotencyKey);
        } else {
            requestIdempotencyKey = this.idempotencyKey;
        }
        return ImmutableMap.builder().put("Idempotency-Key", requestIdempotencyKey)
                .putAll(super.getHeaders()).build();
    }

    protected abstract GetRequest handleConflict(HttpClient httpClient, String id);
}