920-environment-diagram.Rmd

# Mapping your local environment diagram {#chapter_environment-diagram}

```{r setup, echo=FALSE, message=FALSE, warning=FALSE}
# These packages are called in almost every chapter of the book:
library(tidyverse)
library(DBI)
library(RPostgres)
library(glue)
library(here)
require(knitr)
library(dbplyr)
library(sqlpetr)
```

## Environment Tools Used in this Chapter
Note that `tidyverse`, `DBI`, `RPostgres`, `glue`, and `knitr` are loaded.  Also, we've sourced the `[db-login-batch-code.R]('r-database-docker/book-src/db-login-batch-code.R')` file which is used to log in to PostgreSQL.

library(rstudioapi)

The following code block defines Tool and versions for the graph that follows.  The information order corresponds to the order shown in the graph.

```{r eval=FALSE, echo=TRUE}
library(DiagrammeR)

## OS information
os_lbl <- .Platform$OS.type
os_ver <- 0
if (os_lbl == 'windows') {
  os_ver <- system2('cmd',stdout = TRUE) %>%
    grep(x = .,pattern = 'Microsoft Windows \\[',value = TRUE) %>%
    gsub(x = .,pattern = "^Microsoft.+Version |\\]", replace = '')
}

if (os_lbl == 'unix' || os_lbl == 'Linux' || os_lbl == 'Mac') {
  os_ver <- system2('uname', '-r', stdout = TRUE)
}

## Command line interface into Docker Apps
## CLI/system2
cli <- array(dim = 3)
cli[1] <- "docker [OPTIONS] COMMAND ARGUMENTS\n\nsystem2(docker,[OPTIONS,]\n, COMMAND,ARGUMENTS)"
cli[2] <- 'docker exec -it sql-pet bash\n\nsystem2(docker,exec -it sql-pet bash)' 
cli[3] <- 'docker exec -ti sql-pet psql -a \n-p 5432 -d dvdrental -U postgres\n\nsystem2(docker,exec -ti sql-pet psql -a \n-p 5432 -d dvdrental -U postgres)'

# R Information
r_lbl       <- names(R.Version())[1:7]
r_ver       <- R.Version()[1:7]

# RStudio Information
rstudio_lbl <- c('RStudio version','Current program mode')
rstudio_ver <- c(as.character(rstudioapi::versionInfo()$version),rstudioapi::versionInfo()$mode)

# Docker Information
docker_lbl <- c('client version','server version')
docker_ver <- system2("docker", "version", stdout = TRUE) %>% 
    grep(x = ., pattern = 'Version',value = TRUE) %>%
    gsub(x = ., pattern = ' +Version: +', replacement = '')

# Linux Information
linux_lbl <- 'Linux Version'
linux_ver <- system2('docker', 'exec -i sql-pet /bin/uname -r', stdout = TRUE)

# PostgreSQL Information
con <- sp_get_postgres_connection(user = Sys.getenv("DEFAULT_POSTGRES_USER_NAME"),
                         password = Sys.getenv("DEFAULT_POSTGRES_PASSWORD"),
                         dbname = "dvdrental",
                         seconds_to_test = 30)

postgres_ver <- dbGetQuery(con,"select version()") %>%
  gsub(x = ., pattern = '\\(.*$', replacement = '')

```

The following code block uses the data generated from the previous code block as input to the subgraphs, the ones outlined in red.  The application nodes are the parents of the subgraphs and are not outlined in red.  The `Environment` application node represents the machine you are running the tutorial on and hosts the sub-applications.  

Note that the '@@' variables are populated at the end of the `Environment` definition following the `## @@1 - @@5` source data comment.


```{r eval=FALSE, echo=TRUE}
grViz("
digraph Envgraph {

  # graph, node, and edge definitions
  graph [compound = true, nodesep = .5, ranksep = .25,
         color = red]

  node [fontname = Helvetica, fontcolor = darkslategray,
        shape = rectangle, fixedsize = true, width = 1,
        color = darkslategray]

  edge [color = grey, arrowhead = none, arrowtail = none]

  # subgraph for Environment information
  subgraph cluster1 {
    node [fixedsize = true, width = 3]
    '@@1-1' 
  }

  # subgraph for R information
  subgraph cluster2 {
    node [fixedsize = true, width = 3]
    '@@2-1' -> '@@2-2' -> '@@2-3' -> '@@2-4'
    '@@2-4' -> '@@2-5' -> '@@2-6' -> '@@2-7'
  }

  # subgraph for RStudio information
  subgraph cluster3 {
    node [fixedsize = true, width = 3]
    '@@3-1' -> '@@3-2'
  }

  # subgraph for Docker information
  subgraph cluster4 {
    node [fixedsize = true, width = 3]
    '@@4-1' -> '@@4-2'
  }

  # subgraph for Docker-Linux information
  subgraph cluster5 {
    node [fixedsize = true, width = 3]
    '@@5-1' 
  }

  # subgraph for Docker-PostgreSQL information
  subgraph cluster6 {
    node [fixedsize = true, width = 3]
    '@@6-1' 
  }

  # subgraph for Docker-PostgreSQL information
  subgraph cluster7 {
    node [fixedsize = true, height = 1.25, width = 4.0]
    '@@7-1' -> '@@7-2' -> '@@7-3'
  }

  CLI [label='CLI\nRStudio system2',height = .75,width=3.0, color = 'blue' ]
  Environment             [label = 'Linux,Mac,Windows',width = 2.5]
  Environment -> R
  Environment -> RStudio
  Environment -> Docker

  Environment -> '@@1'    [lhead = cluster1] # Environment Information
  R           -> '@@2-1'  [lhead = cluster2] # R Information
  RStudio     -> '@@3'    [lhead = cluster3] # RStudio Information
  Docker      -> '@@4'    [lhead = cluster4] # Docker Information
  Docker      -> '@@5'    [lhead = cluster5] # Docker-Linux Information
  Docker      -> '@@6'    [lhead = cluster6] # Docker-PostgreSQL Information

  '@@1' -> CLI
  CLI         -> '@@7'    [lhead = cluster7] # CLI 
  '@@7-2'     -> '@@5'
  '@@7-3'     -> '@@6'
}
[1]: paste0(os_lbl,     ':\\n', os_ver)
[2]: paste0(r_lbl,      ':\\n', r_ver)
[3]: paste0(rstudio_lbl,':\\n', rstudio_ver)
[4]: paste0(docker_lbl, ':\\n', docker_ver)
[5]: paste0(linux_lbl,  ':\\n', linux_ver)
[6]: paste0('PostgreSQL:\\n', postgres_ver)
[7]: cli
")
```

One sub-application not shown above is your local console/terminal/CLI application.  In the tutorial, fully constructed docker commands are printed out and then executed.  If for some reason the executed docker command fails, one can copy and paste it into your local terminal window to see additional error information.  Failures seem more prevalent in the Windows environment.

## Communicating with Docker Applications

In this tutorial, the two main ways to interface with the applications in the Docker container are through the CLI or the RStudio `system2` command.  The blue box in the diagram above represents these two interfaces.