complete jq exersice

Author: shaghayeghfar

implement-shell-tools/cat/cat.js

@@ -0,0 +1,54 @@
+const fs = require("fs");
+const path = require("path");
+
+// arguments
+const args = process.argv.slice(2);
+
+let isNumbered = false;
+let isNumberNonEmpty = false;
+const filePaths = [];
+
+// parse args
+args.forEach((arg) => {
+  if (arg === "-n") {
+    isNumbered = true;
+  } else if (arg === "-b") {
+    isNumberNonEmpty = true;
+  } else {
+    filePaths.push(arg);
+  }
+});
+
+// -b overrides -n
+if (isNumberNonEmpty) {
+  isNumbered = false;
+}
+
+let lineNumber = 1;
+
+// process files
+filePaths.forEach((filePath, fileIndex) => {
+  const content = fs.readFileSync(filePath, "utf-8");
+
+  // split lines but keep empty ones
+  const lines = content.split("\n");
+
+  lines.forEach((line, index) => {
+    const isLastLineOfLastFile =
+      fileIndex === filePaths.length - 1 && index === lines.length - 1;
+
+    if (isNumberNonEmpty) {
+      if (line !== "") {
+        console.log(`${lineNumber} ${line}`);
+        lineNumber++;
+      } else {
+        console.log(line);
+      }
+    } else if (isNumbered) {
+      console.log(`${lineNumber} ${line}`);
+      lineNumber++;
+    } else {
+      console.log(line);
+    }
+  });
+});

implement-shell-tools/ls/ls.js

@@ -0,0 +1,35 @@
+const fs = require("fs");
+
+// Get command line arguments
+const args = process.argv.slice(2);
+
+// Default settings
+let showAll = false;
+let onePerLine = false;
+let dir = ".";
+
+// Parse arguments
+args.forEach((arg) => {
+  if (arg === "-a") {
+    showAll = true;
+  } else if (arg === "-1") {
+    onePerLine = true;
+  } else {
+    dir = arg;
+  }
+});
+
+// Read directory contents
+let files = fs.readdirSync(dir);
+
+// Filter hidden files if -a is NOT used
+if (!showAll) {
+  files = files.filter((file) => !file.startsWith("."));
+}
+
+// Output
+if (onePerLine) {
+  files.forEach((file) => console.log(file));
+} else {
+  console.log(files.join("  "));
+}

jq/script-01.sh

@@ -5,3 +5,5 @@ set -euo pipefail
 # The input for this script is the person.json file.
 # TODO: Write a command to output the name of the person.
 # Your output should be exactly the string "Selma", but should not contain any quote characters.
+
+jq -r '.name' person.json

jq/script-02.sh

@@ -5,3 +5,5 @@ set -euo pipefail
 # The input for this script is the person.json file.
 # TODO: Write a command to output the address of the person, all on one line, with a comma between each line.
 # Your output should be exactly the string "35 Fashion Street, London, E1 6PX", but should not contain any quote characters.
+
+jq -r '.address | join(", ")' person.json

jq/script-03.sh

@@ -5,3 +5,5 @@ set -euo pipefail
 # The input for this script is the person.json file.
 # TODO: Write a command to output the name of the person, then a comma, then their profession.
 # Your output should be exactly the string "Selma, Software Engineer", but should not contain any quote characters.
+
+jq -r '"\(.name), \(.profession)"' person.json

jq/script-04.sh

@@ -6,3 +6,5 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player, one per line.
 # Your output should contain 6 lines, each with just one word on it.
 # Your output should not contain any quote characters.
+
+jq -r '.[].name' scores.json

jq/script-05.sh

@@ -5,3 +5,5 @@ set -euo pipefail
 # The input for this script is the scores.json file.
 # TODO: Write a command to output the names of each player, as well as their city.
 # Your output should contain 6 lines, each with two words on it.
+
+jq -r '.[] | "\(.name) \(.city)"' scores.json

jq/script-06.sh

@@ -6,3 +6,5 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player along with the score from their first attempt.
 # Your output should contain 6 lines, each with one word and one number on it.
 # The first line should be "Ahmed 1" with no quotes.
+
+jq -r '.[] | "\(.name) \(.scores[0])"' scores.json

jq/script-07.sh

@@ -6,3 +6,5 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player along with the score from their last attempt.
 # Your output should contain 6 lines, each with one word and one number on it.
 # The first line should be "Ahmed 4" with no quotes.
+
+jq -r '.[] | "\(.name) \(.scores[-1])"' scores.json

jq/script-08.sh

@@ -6,3 +6,5 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player along with the number of times they've played the game.
 # Your output should contain 6 lines, each with one word and one number on it.
 # The first line should be "Ahmed 3" with no quotes.
+
+jq -r '.[] | "\(.name) \(.scores | length)"' scores.json