Here are some quick key chords for navigating TAGS in Emacs.
| Key Chord | Description |
|---|---|
| M-x visit-tags-table | load a tags file |
| M-. tag | find a tag |
| C-u M-. | go to next tag (if more than one) |
| M-* | go back to the previous spot |
| C-x 4 . tag | open tag in split screen |
| C-M-. pattern | search for tag by pattern |
| TAB | auto complete |
I'm trying to use Docker to build my local development environment on my Mac. (I don't want to have to rebuild my laptop as I try new things and experiment. That usually dirties up my laptop.) To that end, I'm working with two containers to implement different technology stacks for development.
My ideal set up would be to implement my entire developer experience in Docker. I would like to run Emacs out of one container, run tech stack tooling out of another container, and pull my Git repos into the tech stack repos as necessary. (Previously I've written about running GUI apps out of Docker containers on a Mac. Since that writing, I have upgraded to Docker for Mac from Docker Toolbox. Since that upgrade, I have been unable to get GUI apps to run out of a Docker container.) For my current purposes, I am running my tech stacks out of Docker containers, mounting my source code from local folders into the containers, and running Emacs locally.
The first container I created was for .NET Core development. This environment allows me to do .NET Core development natively on my Mac. I'm developing in .NET Core with Emacs. I'm also trying to use Omnisharp with Emacs. Since Omnisharp is a work in progress, I wanted to set up this development environment in a way that makes it easy to blow away and restart. I used the Microsoft supplied development image, and it works great for building .NET Core projects. I'm still struggling to get it to expose ports correctly, both for .NET apps and Omnisharp.
The second container I created is for NodeJS work. I used the NodeJS image to create my container. Right now I'm using this container for running AngularJS 1.x apps, and it is working pretty well. The ports are exposed correctly and I can access the apps externally from the container.
Since this is a work-in-progress, I'm keeping my "notes" in the form of Dockerfiles and shell scripts. These are being stored in this Github repo. This work may be of some use to others as they build similar environments. If nothing else, I should be able to find my previous experiments.
I recently attended a training session on writing requirements that was geared for product managers. I sat in on the third day of a 3-day course. The day consisted mostly of how to create and prioritize requirements for feeding into development teams.
The instructor focused on the following aspects:
There was an undercurrent in many of the statements that seemed to reinforce an us-versus-them mentality between product managers and software developers. I think this undercurrent missed the mark and is probably doing more harm than good.
I have seen a lot of success over the last decade as a software developer at Clearent expressly because there has been a strong relationship between product management and software development. As the manager of a software team, I have pushed my team to learn and understand our industry along with our particular approach to doing business. I joke with my boss that members of my team spend more time learning the business than they do any of our technology. This learning has allowed my team to work as a partner with product management to creatively build tools and solutions that set us apart in the industry.
On the other side, product management has taken a LOT of time to provide context and education for my team so that they can get smarter about our business. All of our major development efforts start with several discussions about the business needs and the landscape of the problem we are trying to solve. My team is never in the dark about the motivations behind the changes we are making.
Together, we can have productive conversations about technical debt and business needs. The development team can raise concerns over technical debt. The product management team can talk to business needs that will help propel us forward. Because the dialog is good, we always find a good balance between the two concerns.
Healthy dialog between product management and development is the key to successful software development projects. This dialog exists in the close relationship we have at Clearent between product management and software development.
I hope it exists in your job too!
In an earlier post I wrote about the golf score tracking application I created to learn ASP.NET Core and AngularJS. Since the initial inspiration was my son playing golf, I thought it would be good to put the application on his tablet so he could track his own scores. Cordova looked like the technology to allow me to turn my "experiment" into something my son could practically use.
I'm going to focus on my experience with Cordova and getting a mobile app running. (I'm writing this post mostly so that I don't forget the little things I ran into while getting things to work.)
Cordova is an Apache open-source project for building mobile applications using web-based technologies. I have heard about this technology for a few years at several tech conferences that I attend. The appeal of Cordova is that it should allow a developer to publish an application to multiple mobile platforms using the web-based technology that is already known. Cordova was born out of a technology called PhoneGap.
The Cordova utilities run on Node.js and can be installed using the Node Package Manager (NPM). The Getting Started page of the Cordova site has all of the basic steps necessary to get Cordova installed and the first application created. Here are the steps I followed:
npm install -g cordova
cordova create com.darrenhale.golfscoretracker golfscoretrackerThis step is different than the step listed on the Cordova Getting Started page. I was required to include the "com.darrenhale.golfscoretracker" portion to generate the application structure.
cordova add platform browser android ios
cordova run browser
Up to this point, things were great! The application worked when I called:
cordova run browserI had also started my web API application to have a back-end process. Everything worked as expected! (I expected it to work since the AngularJS app worked in a browser already.) My next step was to run it for a mobile platform.
In my excitement, I quickly executed:
cordova run androidGuess what happened? Nothing. It was late, and I realized I was not thinking straight. It dawned on me that I needed an Android emulator to make this command work. Let the adventure begin!
At my next opportunity to work on the project, I immediately went to get the Android SDK and its corresponding emulator. I didn't realize how much the state of mobile development has changed, and I was surprised to find that the first thing I found was Android Studio. I really didn't want to download a full development environment. After some poking around I was able to find just the Android command line tools. I downloaded the package for Mac OS X and unzipped the package into a folder on my system.
I created a test device to emulate for running my application. Through trial and error, I came up with the following configuration:
With the emulator running, I executed:
cordova run androidThe Cordova utilities packaged my application, pushed it to the emulator, and started the application. It worked! My application started up and functioned! I realized I needed to adjust the CSS in the app to work on a smaller display, but those changes were straightforward to make. After a little more trial and error, I had an application that functioned on a mobile device.
The last change I needed to make was to replace the API calls in the application with calls to localstorage. I opted to use localstorage for two reasons: first, I wanted my son to be able to use this application without any network connectivity, and second, localstorage is a mechanism that a Cordova app can use across multiple platforms. Localstorage is essentially a key/value store using JSON as the storage mechanism. Most of the data in the golf score app is pretty simple, so I figured I could make this work. The localstorage object has a setItem() method for saving data and a getItem() method for retrieving data. I was able to replace my API calls with localstorage calls fairly easily, but the app didn't work right away. The trick I was missing was that I needed to convert my objects into a JSON format to save them and to parse JSON into my object when retrieving them. I accomplished this with JSON.stringify() and JSON.parse() respectively.
My path for learning Cordova is not unique, and I'm sure many of the challenges I have experienced aren't challenges for experienced mobile developers or Javascript developers. It was still a great learning experience and it has me excited to do more Javascript coding!
I read Walter L. Metcalfe Jr.'s editorial this morning in the St. Louis Post-Dispatch. In his editorial, he calls on St. Louis to start a new competition similar to the one that brought us the Gateway Arch to spur collaboration and innovation. While reading this article, I couldn't help but think of hackathons.
Hackathons are generally time-limited competitions in which technology specialists work to create prototype solutions to problems. Sometimes these problems are business-oriented, but quite often the problems are civic focused. These competitions require teams of people to work together to solve the problem.
My company Clearent and the University of Missouri - St. Louis are partnering for a competition in the same spirit as Mr. Metcalfe is calling for, but on a smaller scale. We are sponsoring a hackathon called HackEdu. This is an inaugural event in which we are going to bring together educators, technology specialists, and business people to solve some of the most pressing challenges in education using cutting edge technologies. HackEdu has several goals in mind.
First and foremost, we want to introduce many different constituent groups to each other, and help them learn how to collaborate together effectively. Quite often we see divisions between educators, business people, and technologists. This division limits innovation, especially in the education sector. Within the context of the HackEdu, we want to help these different groups learn how to work together effectively.
Another goal of this event is to teach participants how to to function in a hackathon. Many participants in a hackathon don't have the tools necessary to implement a process that helps them effectively achieve their goals. During the HackEdu event, we plan to introduce participants to a methodology that Clearent uses to develop software. Our process focuses on business value, features, and functions. This approach allows us to break down business goals into smaller features and ultimately individual functions that allow us to incrementally release software that provides value quickly.
The obvious goal of the HackEdu event is to solve a problem related to education. A specific problem will be announced at the event, but it will focus on an educational need that could benefit from a technology-oriented solution.
Because much of the HackEdu event is directed toward teaching people how to collaborate and create functional solutions, we are offering the winners of the HackEdu tickets to Globalhack VI. Globalhack is an annual hackathon where numerous teams come together to solve a civic-oriented problem. Our hope is to prepare people to effectively compete in the Globalhack event this year.
I believe that the HackEdu competition and the Globalhack event are preparing people in St. Louis to participate in a competition like the one Mr. Metcalfe describes in his editorial. If nothing else, I think we are building the skills necessary to continue to build the St. Louis area as a colloborative, innovative community!
I've been trying to learn the new ASP.NET Core technology along with AngularJS. I always find it easier to learn new technology if I have some problem that I'm trying to solve. The problem that presented itself to me was a golf score tracking application. My middle son plays golf for his school team. I thought it would be great to build a mobile app to keep track of his golf score on the course. Since I've never been great at UI work, I thought this was a good opportunity to learn a front-end technology too.
I created an MVC 6 web API that exposes REST endpoints for working with a golf score. My intention with the application is to mimic a golf score card. The API went together pretty quickly. I kept the API simple: I have a single controller that exposes GET, PUT, POST, and DELETE methods on the Score object. The Score object holds some basic information about a round of golf (i.e. the course name and a description) along with a collection of scores for holes. The controller is saving data to a text file. I used a text file instead of a database to simplify the learning process. (Another motivation for saving to a text file instead of a database was because DNX Beta 4 did not have the ability to work with a SQL Server database, and I didn't want to hunt down a compatible technology.) Over the last several months, I've upgraded the back-end portion of the app to stay up-to-date with the ASP.NET Core changes, bringing it up to RC1.
The front-end of the application is an AngularJS application using Bootstrap for styling. At the time I created the initial application, I also wanted to learn some of the modern web tooling, including Bower. I used Bower to lay down the initial AngularJS application, but I quickly abandoned keeping up with Bower becase I had my hands full just learning AngularJS and Bootstrap.
I experienced two main difficulties creating the web application. First, I had a difficult time understanding AngularJS routes, views, controllers, and the relationships between them. Once I started to "get" how things were wired together, I was able to I went through several passes to get an application functional. The Javascript code is not pretty and probably not well organized. My focus was on understanding learning AngularJS and not making things "pretty."
I'm not a developer that is good at creating large amounts of documentation for my code. I generally want code to stand for itself. To that end, this project is in Github here. Hopefully the code does actually speak for itself.
In future passes, I would like to clean up the Javascript and add unit testing to both the API and Angular pieces. I also plan on upgrading this app to RC2 of ASP.NET Core when it is released. (I may try to do this sooner if time allows.)
I've been trying to figure out how to run GUI apps in a Docker container on my Mac running OS X El Capitan. As a developer, I try out many different software packages and configurations. I would love to be able to try out certain things in a well-contained environment where I won't leave bits and pieces lying around if something doesn't work or if I get bored with the package. I have also been enamored with using Docker for development environments to make them portable and self-contained. After many searches and experiments, I finally stumbled on what I needed to do.
I am using the Docker Toolbox to run Docker on my Mac. I have also used Boot2Docker, but the Docker Toolbox experience is a little smoother. Either option will work to get Docker containers running on your system.
One of the required pieces I had to install was XQuartz. This is an X11 windowing system that runs on the Mac. I was originally worried about installing this package, concerned that it would interfere with the X11 windowing system built into OS X. So far, I haven't had any trouble with it.
To try out a GUI app, I wanted a basic Linux container with an obvious GUI app that is not installed on my Mac. I created a basic Dockerfile defining an image based on the latest distribution of Ubuntu. I then install Firefox into the image. The image starts up at a bash prompt, which allows me to run programs. Here is that docker file:
FROM ubuntu:latest RUN apt-get update && apt-get install -y firefox CMD /bin/bash
Getting Docker to create an image and run a container based on that image was pretty straightforward with the Docker Toolbox for Mac OS X. The hardest part was trying to get the running container to bind the DISPLAY environment variable to the XQuartz server. This link finally broke things open for me. A comment from slobo on January 22, 2015 has the secret sauce. In an xterm window started under XQuartz, run the command
socat TCP-LISTEN:6000,reuseaddr,fork UNIX-CLIENT:\"$DISPLAY\"Then, when starting the container, set the DISPLAY environment variable to the IP of the Docker virtual machine. (This IP address is usually a 192.168.x.x value.) I found this IP address on my Mac by typing
ifconfigand locating the vboxnetn entry (where n is 0 - 9). For me, it looked like:
Using the IP address 192.168.99.1, I ran the following command to start a running container:
docker run -it -e DISPLAY=192.168.99.1:0 firefox(firefox is the image name for the Ubuntu image running Firefox I defined with the Dockerfile above.) When I got to the bash prompt inside the running container, I ran Firefox, and the UI appeared like another window in OS X!
I am just starting my journey with Docker, but I'm excited about the possibilities it offers.
Benny Cornelissen (@whieee) has a blog post that does a really good job integrating XQuartz and the instantiation of containers into the bash shell.
Here is a link to a StackOverflow article outlining how to do this.
I actually found something that so far does what I asked for, sharing here so anyone who runs into this issue can try out this solution:
sudo setfacl -Rdm g:groupnamehere:rwx /base/path/members/ sudo setfacl -Rm g:groupnamehere:rwx /base/path/members/
R is recursive, which means everything under that directory will have the rule applied to it. d is default, which means for all future items created under that directory, have these rules apply by default. m is needed to add/modify rules.
The first command, is for new items (hence the d), the second command, is for old/existing items under the folder. Hope this helps someone out as this stuff is a bit complicated and not very intuitive.
Recently, Team Foundation Server (TFS) has added some new features that my team is using. One of these features is the new Epic work item. We are using epics to track high-level business initiatives, with features underneath the epics to track user requirements. Underneath the features, we have user stories, which are self-contained units of work that can be tested and deployed independently. My team works with user stories and tracks everything through user stories. I need to drive my reporting by user stories but relate the data to the epics that they are under.
The built-in reporting capabilities of TFS are pretty good, but they don't handle the kind of roll-up reporting I need. A consultant friend shared some code snippets with me that use the TFS API to pull data from the TFS database. I'm building out my custom reporting using the TFS API. One of the first challenges I've run into is starting with a user story and determining the epic that contains that story.
I struggled trying to understand how to follow the links that are available on a TFS WorkItem object. This link pushed my understanding forward quickly. It helped me understand how to identify the "type" of link that I was seeing.
"The tricky bit" for me is identifying the type of link I'm dealing with. Here is the code snippet to do that:
if (link.LinkTypeEnd.Name == "Parent")In this code snippet, I am filtering on links that are of type "Parent." One could easily filter on other types of links based on need.
As I develop my TFS reporting capability, I will document what I'm doing to make it less mysterious for others.
My middle son's Pinewood Derby for Cub Scouts was about a month ago. His pack usually has an "outlaw" division for dads, siblings, and other family members to submit cars. Usually I don't submit a car for the derby, but this year I decided to create a car powered by Arduino.
My original idea was to put a motion sensor on the car, have the Arduino detect that the car was moving, and start up a motor with a propeller. The way the project played out, I got the Arduino kit about 3 days before the Pinewood Derby, so I had to throw something together very quickly.
I cut the car into a basic platform, with a cut-out intended for the motor. I slapped some black paint on it to cover the wood and mounted the wheels. I didn't put any time into making it faster or straight because my intention was not to win a race.
Next I had to do something with the Arduino. I purchased the Arduino Uno with a basic electronics kit. The kit came with jumper wires, resistors, and numerous sensors. It was perfect! I spent a few hours installing the Arduino IDE and playing around with sample sketches. Now I was ready for my project.
My initial idea of driving a motor with the Arduino was doomed to fail. First off, I needed a 5V battery to power the Arduino. I really didn't have room on the car for the Arduino board, battery, and motor. (If I had more time, I would have used an Arduino micro.) Second, not being an electrical engineer, I didn't realize I needed a relay switch to power the Arduino and the motor from the same battery. This realization put my whole project in jeopardy.
At this point I was frantically scrambling to come up with something I could do for this project. I settled on mounting the active buzzer component, with a ball switch. I found a sketch that set up all the notes on the scale and played a melody repeatedly through the buzzer. I wired the buzzer into the Arduino board with the ball switch so that the melody only played when the car was angled downward. (This ensured that the car wasn't annoying everyone unless it was perched for a race.)
The project came together as a family effort. My oldest son helped me mount the board to the car while I figured out how to get the electronic components mounted. My middle son helped me figure out the first few notes of the Imperial March (think Darth Vader theme song) so I could program that into the sketch. I used the space for the motor to mount the battery, and was able to get something together. Here is a picture of the car.
The code I downloaded and modified to play the Imperial March is here on Github.
Even though the project didn't come out as I expected it, it had the desired effect. Numerous adults and scouts asked me about the car. They were all interested in how it worked and what it did. This was exactly the purpose of the project.
I wanted to show the scouts that something like the Pinewood Derby could be looked at through a different lens. I wanted to show the kids that technology can be used in different ways, even on a wooden block with wheels. Although it wasn't perfect, I'm still proud of my first IoT project!
The St. Ferdinand Men's Club has been reviewing the four signs of a Dynamic Catholic from the book by Matthew Kelly. I was supposed to do a brief presentation at our February meeting, but it got bumped due to a full schedule. Since I'm not sure if it will get rescheduled or not, I thought I would convert it into a blog post.
The first sign we covered was prayer. We covered it first because it is the first sign in the book, and because I feel it is the basis for everything we do as Catholics. The next sign I was going to cover is evangelization. I skipped ahead because I think this is the toughest of the four signs, and I think it is one of the most critical for our parish at this time.
What is evangelization? Fundamentally, evangelization is sharing our faith with others. It is being open to opportunities to talk about our faith, our faith journey, and our practice of the faith. Evangelization is also about sharing our faith with our faith community (parish) and helping to bolster our fellow parishioners.
When I want to understand how to evangelize, I turn to the saints. The first saint I look to is St. Rose Philippine Duchesne. She is the dedicated religious that founded St. Ferdinand school and helped bring Catholicism west of the Mississippi river. She evangelized by working for the poor, building schools to teach the faith, and by supporting the missionaries in any way she could.
Another person I look to for help understanding evangelization is Fr. Pierre De Smet. He was a Jesuit missionary in America, whose "home base" was St. Louis. He was instrumental in establishing missions in Florissant, MO, Kansas, and Oregon. He made great strides converting Native American tribes by learning their language, understanding their customs, and adapting his approach to their particular needs. Fr. De Smet's peaceful approach to evangelization earned him the respect of most of the Native American tribes west of the Mississippi.
Stories of holy people moving thousands of miles from home to start missions and teach poor kids are exciting and romantic. They make evangelization seem intimidating for most ordinary people. The key is to understand that St. Rose and Fr. De Smet had particular callings that spoke to their characters, allowing them to do these things. Most of us are called to evangelize in simpler ways.
St. Rose, despite her accomplishments starting schools, was most known for her prayer life. She was known by the Native Americans as the Woman-Who-Prays-Always. Her contemporaries were convinced of her holiness because of her diligence in prayer.
Fr. De Smet gained the respect of the Native Americans he worked with in several simple ways. He learned their language and customs, helped broker peace between tribes, and treated them with respect. His success came from simply living as a Christian.
So, who should evangelize? The short answer is: EVERYONE! We should all feel called to share our faith with others. If we have truly embraced Christianity and its way of life, we should be eager to share it with others.
How should we evangelize? First and foremost, we should evangelize through the example of our lives. We should live as Christians are called to live by Jesus Christ. That example was compelling enough to draw thousands to the church in the days immediately after the Ascension. It is good enough to work today.
We are also called to evangelize by telling our story. A great way to to get people curious about the faith is to share with them what drives you in your faith. The compelling personal story goes a long way to drawing people to the Lord.
A critical way we evangelize is by supporting our faith community. My cousin always signs his emails with the tag line "Keep the faith." I used to think it was a catchy platitude, but now I see the brilliance of it. Keeping the faith is difficult, and it needs the support of a strong faith community. By participating in our faith community, we bolster the faith of others and make them strong to evangelize too.
So how do we, as modern Christians, draw others to Jesus?
