bdkosher

Liberating an API Codebase from Swagger Annotations

When creating an API with accompanying Swagger documentation, two general paths can be taken:

1. Build First: Implement the API --> add Swagger annotations --> generate the UI and clients from the annotations
2. Design First: Design the API spec in Swagger YAML or JSON --> generate the UI, clients, and server stubs from the spec --> implement the server stubs

On my recent project, we had embarked down the "Build First" path. After implementing the API using the mighty Spring Boot, we integrated Swagger using the slick SpringFox library, as widely demonstrated in numerous blog posts.

But all w

bdkosher

package bdkosher.datetime;

import java.util.Calendar;
import static java.util.Calendar.*;
import java.util.Date;
import java.util.Locale;
import java.util.SortedSet;
import java.util.TimeZone;
import java.util.TreeSet;

bdkosher

// these 9 characters represent our days: 2 days of rain ('R') and 7 days of dryness ('D')
def days = 'RRDDDDDDD' as List

// number of trials to run; the bigger the number, the more accurate the probability
int trials = 10000 

// counter for the number of consecutive rainy days we see
int consecutiveRainyDays = 0 

// run the trials

bdkosher

@Grab(group='org.apache.pdfbox', module='pdfbox', version='2.0.21')
import org.apache.pdfbox.multipdf.PDFMergerUtility
import org.apache.pdfbox.io.MemoryUsageSetting

def dir = new File('C:\\Users\\Joe\\Documents\\pdfs')

def merger = new PDFMergerUtility();
(1..3).each { merger.addSource(new File(dir, "document_page${it}.pdf")) }
merger.destinationFileName = new File(dir, "document.pdf").absolutePath

bdkosher

When concrete classes are preferrable to interfaces

String vs. CharSequence
- better relays immutability?
- so widespread that it can be an inconvenience to accept a CharSequence and have to do something with it, like pass to another 3rd party library method

Exception vs. Throwable
- error details object in REST application, don't want people to attempt to create these if there's an Error

LocalDate vs. ChronoLocalDate

bdkosher

import java.time.temporal.*;

import static java.time.Month.OCTOBER;
import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
import static java.time.temporal.ChronoField.YEAR;

/**
 * Temporal fields that are commonly used within the Federal government.
 *
 * More fields may be added in the future (e.g. Leave Year, Bi-Weekly Pay Period)

bdkosher

import java.time.DayOfWeek;
import java.time.LocalDate;
import java.time.Month;
import java.time.MonthDay;
import java.time.temporal.TemporalAdjusters;
import java.util.*;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

bdkosher

@Grab(group='org.springframework.security', module='spring-security-core', version='3.2.5.RELEASE')
@Grab(group='org.springframework.security', module='spring-security-ldap', version='3.2.5.RELEASE')

import groovy.transform.*
import javax.naming.NamingException
import javax.naming.directory.Attribute
import javax.naming.directory.Attributes
import org.springframework.ldap.core.*
import org.springframework.security.ldap.*

bdkosher

println groovy.json.JsonOutput.prettyPrint(new File(args[0]).text)

bdkosher

import groovy.transform.*
import java.nio.*
import java.nio.charset.*

@Field CharsetDecoder cs = Charset.forName('UTF-8').newDecoder()
InputStream.metaClass.eachChunk << { int preferredChunkSize, Closure closure ->
    delegate.eachByte(preferredChunkSize) { buffer, bytesRead ->
        if (bytesRead == preferredChunkSize) {
            closure(buffer)
        } else if (bytesRead > 0) {